Publications by authors named "Jackie Benschop"

44 Publications

An evaluation of diagnostic tests in a case series of suspected leptospirosis patients seen in primary care.

N Z Med J 2021 Jul 30;134(1539):33-43. Epub 2021 Jul 30.

Professor of Veterinary Public Health, Molecular Epidemiology and Public Health Laboratory, School of Veterinary Science, Massey University, Palmerston North.

Aims: This study describes 47 presentations of suspected leptospirosis in general practice in New Zealand. Our primary aim was to assess the laboratory diagnosis of leptospirosis in these patients, by comparing polymerase chain reaction (PCR) tests, microscopic agglutination test (MAT) and culture results.

Methods: Patients suspected of leptospirosis were recruited from general practices in the Waikato (n=17) and Wairoa (n=30) between August 2011 and June 2015. Blood and urine samples were tested for leptospirosis at two diagnostic laboratories and one research laboratory using PCR tests, MAT and culture.

Results: Forty-seven patients were recruited for this study: 37 during the acute phase of the illness (within 10 days of symptom onset) and 10 after the acute phase. Eleven of the acute phase patients (11/37, 30%) and two of the later phase patients (2/10, 20%) returned positive leptospirosis test results. The 11 acute phase leptospirosis positive patients had the following positive diagnostic tests: PCR and paired MAT (+/- blood culture) (n=3), PCR only (+/- blood culture) (n=4), paired MAT only (n=3) and blood culture only (n=1). Urine PCR (performed only on Wairoa patients) was the only positive test for two of these patients.

Conclusion: About a quarter of farm workers and meat workers presenting to general practice with flu-like symptoms will have leptospirosis, but they will not be diagnosed unless appropriately tested, and then they may only test positive for some of the tests available. To increase the likelihood of making a diagnosis, clinicians should order multiple laboratory tests, including blood and urine PCR and a paired MAT.
View Article and Find Full Text PDF

Download full-text PDF

Source
July 2021

Transmission Dynamics of Shiga Toxin-Producing Escherichia coli in New Zealand Cattle from Farm to Slaughter.

Appl Environ Microbiol 2021 05 11;87(11). Epub 2021 May 11.

EpiLab, School of Veterinary Science, Massey University, Palmerston North, New Zealand.

Cattle are asymptomatic carriers of Shiga toxin-producing (STEC) strains that can cause serious illness or death in humans. In New Zealand, contact with cattle feces and living near cattle populations are known risk factors for human STEC infection. Contamination of fresh meat with STEC strains also leads to the potential for rejection of consignments by importing countries. We used a combination of PCR/matrix-assisted laser desorption ionization-time of flight mass spectrometry (MALDI-TOF) and whole-genome sequencing (WGS) to evaluate the presence and transmission of STEC on farms and in processing plants to better understand the potential pathways for human exposure and thus mitigate risk. Animal and environmental samples ( = 2,580) were collected from six farms and three meat processing plants in New Zealand during multiple sampling sessions in spring of 2015 and 2016. PCR/MALDI-TOF analysis revealed that 6.2% were positive for "Top 7" STEC. Top 7 STEC strains were identified in all sample sources ( = 17) tested. A marked increase in Top 7 STEC prevalence was observed between calf hides on farm (6.3% prevalence) and calf hides at processing plants (25.1% prevalence). Whole-genome sequencing was performed on Top 7 STEC bacterial isolates ( = 40). Analysis of STEC O26 ( = 25 isolates) revealed relatively low genetic diversity on individual farms, consistent with the presence of a resident strain disseminated within the farm environment. Public health efforts should focus on minimizing human contact with fecal material on farms and during handling, transport, and slaughter of calves. Meat processing plants should focus on minimizing cross-contamination between the hides of calves in a cohort during transport, lairage, and slaughter. Cattle are asymptomatic carriers of Shiga toxin-producing (STEC) strains, which can cause serious illness or death in humans. Contact with cattle feces and living near cattle are known risk factors for human STEC infection. This study evaluated STEC carriage in young calves and the farm environment with an in-depth evaluation of six farms and three meat processing plants over 2 years. An advanced molecular detection method and whole-genome sequencing were used to provide a detailed evaluation of the transmission of STEC both within and between farms. The study revealed widespread STEC contamination within the farm environment, but no evidence of recent spread between farms. Contamination of young dairy calf hides increased following transport and holding at meat processing plants. The elimination of STEC in farm environments may be very difficult given the multiple transmission routes; interventions should be targeted at decreasing fecal contamination of calf hides during transport, lairage, and processing.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1128/AEM.02907-20DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8208155PMC
May 2021

Still 'dairy farm fever'? A Bayesian model for leptospirosis notification data in New Zealand.

J R Soc Interface 2021 02 17;18(175):20200964. Epub 2021 Feb 17.

Department of Statistics, University of Warwick, Coventry, UK.

Routinely collected public health surveillance data are often partially complete, yet remain a useful source by which to monitor incidence and track progress during disease intervention. In the 1970s, leptospirosis in New Zealand (NZ) was known as 'dairy farm fever' and the disease was frequently associated with serovars Hardjo and Pomona. To reduce infection, interventions such as vaccination of dairy cattle with these two serovars was implemented. These interventions have been associated with significant reduction in leptospirosis incidence, however, livestock-based occupations continue to predominate notifications. In recent years, diagnosis is increasingly made by nucleic acid detection which currently does not provide serovar information. Serovar information can assist in linking the recognized maintenance host, such as livestock and wildlife, to infecting serovars in human cases which can feed back into the design of intervention strategies. In this study, confirmed and probable leptospirosis notification data from 1 January 1999 to 31 December 2016 were used to build a model to impute the number of cases from different occupational groups based on serovar and month of occurrence. We imputed missing occupation and serovar data within a Bayesian framework assuming a Poisson process for the occurrence of notified cases. The dataset contained 1430 notified cases, of which 927 had a specific occupation (181 dairy farmers, 45 dry stock farmers, 454 meatworkers, 247 other) while the remaining 503 had non-specified occupations. Of the 1430 cases, 1036 had specified serovars (231 Ballum, 460 Hardjo, 249 Pomona, 96 Tarassovi) while the remaining 394 had an unknown serovar. Thus, 47% (674/1430) of observations had both a serovar and a specific occupation. The results show that although all occupations have some degree of under-reporting, dry stock farmers were most strongly affected and were inferred to contribute as many cases as dairy farmers to the burden of disease, despite dairy farmer being recorded much more frequently. Rather than discard records with some missingness, we have illustrated how mathematical modelling can be used to leverage information from these partially complete cases. Our finding provides important evidence for reassessing the current minimal use of animal vaccinations in dry stock. Improving the capture of specific farming type in case report forms is an important next step.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1098/rsif.2020.0964DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8086863PMC
February 2021

Seroprevalence of in Racehorses and Broodmares in New Zealand.

Animals (Basel) 2020 Oct 23;10(11). Epub 2020 Oct 23.

School of Veterinary Science, Massey University, Palmerston North 4442, New Zealand.

A cross-sectional survey was conducted to determine the seroprevalence of in a cohort of horses and to evaluate potential risk factors for seropositivity in horses in New Zealand. The convenience sample included 499 Thoroughbred racing and breeding horses from 25 commercial properties in North Island, New Zealand. A questionnaire was used to collect demographic data on horses and property-level information on grazing and management practices, pest (rodent) management, access to natural waterways, other livestock on the property, and possible contact with wildlife. The microscopic agglutination test was used to test sera for serovars Ballum, Copenhageni, Hardjo (bovis), Pomona, and Tarassovi. Logistic regression was used to investigate the risk factors for seropositivity to at least one serovar and for each serovar individually. A total of 124 (25%, 95% confidence interval (CI) 21-29%) horses had positive titres to any one of the five serovars. The seroprevalence of Ballum, Copenhageni, Hardjo (bovis), Pomona, and Tarassovi was 5% (95% CI 3-7%), 9% (95% CI 7-12%), 6% (95% CI 4-8%), 6% (95% CI 4-8%), and 6% (95% CI 4-8%), respectively. Broodmares, compared to racehorses and alternately grazing horses with sheep, increased the odds of exposure to any one serovar, whilst grazing the same time as sheep and alternately grazing horses with cattle increased the odds of exposure to Ballum and Hardjo (bovis), respectively. Historical exposure to in racing and breeding horses was identified, and risk factors were consistent with pasture-based exposure.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.3390/ani10111952DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7690811PMC
October 2020

Diverse Epidemiology of serovars Notified in New Zealand, 1999-2017.

Pathogens 2020 Oct 14;9(10). Epub 2020 Oct 14.

Molecular Epidemiology and Public Health Laboratory, Hopkirk Research Institute, School of Veterinary Science, Massey University, Palmerston North 4474, New Zealand.

Leptospirosis in New Zealand has been strongly associated with animal-contact occupations and with serovars Hardjo and Pomona. However, recent data suggest changes in these patterns, hence, serovar-specific epidemiology of leptospirosis from 1999 to 2017 was investigated. The 19-year average annual incidence is 2.01/100,000. Early (1999-2007) and late (2008-2017) study period comparisons showed a significant increase in notifications with serovar Ballum (IRR: 1.59, 95% CI: 1.22-2.09) in all cases and serovar Tarassovi (IRR: 1.75, 95% CI: 1.13-2.78) in Europeans and a decrease in notifications with serovars Hardjo and Pomona in all cases. Incidences of Ballum peaked in winter, Hardjo peaked in spring and Tarassovi peaked in summer. Incidence was highest in Māori (2.24/100,000) with dominant serovars being Hardjo and Pomona. Stratification by occupation showed meat workers had the highest incidence of Hardjo (57.29/100,000) and Pomona (45.32/100,000), farmers had the highest incidence of Ballum (11.09/100,000) and dairy farmers had the highest incidence of Tarassovi (12.59/100,000). Spatial analysis showed predominance of Hardjo and Pomona in Hawke's Bay, Ballum in West Coast and Northland and Tarassovi in Waikato, Taranaki and Northland. This study highlights the serovar-specific heterogeneity of human leptospirosis in New Zealand that should be considered when developing control and prevention strategies.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.3390/pathogens9100841DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7602385PMC
October 2020

Carriage of Extended-Spectrum-Beta-Lactamase- and AmpC Beta-Lactamase-Producing Escherichia coli Strains from Humans and Pets in the Same Households.

Appl Environ Microbiol 2020 11 24;86(24). Epub 2020 Nov 24.

EpiLab, School of Veterinary Science, Massey University, Palmerston North, New Zealand

Extended-spectrum-beta-lactamase (ESBL)- or AmpC beta-lactamase (ACBL)-producing bacteria are the most common cause of community-acquired multidrug-resistant urinary tract infections (UTIs) in New Zealand. The carriage of antimicrobial-resistant bacteria has been found in both people and pets from the same household; thus, the home environment may be a place where antimicrobial-resistant bacteria are shared between humans and pets. In this study, we sought to determine whether members (pets and people) of the households of human index cases with a UTI caused by an ESBL- or ACBL-producing strain also carried an ESBL- or ACBL-producing strain and, if so, whether it was a clonal match to the index case clinical strain. Index cases with a community-acquired UTI were recruited based on antimicrobial susceptibility testing of urine isolates. Fecal samples were collected from 18 non-index case people and 36 pets across 27 households. Eleven of the 27 households screened had non-index case household members (8/18 people and 5/36 animals) positive for ESBL- and/or ACBL-producing strains. Whole-genome sequence analysis of 125 isolates (including the clinical urine isolates) from these 11 households showed that within seven households, the same strain of ESBL-/ACBL-producing was cultured from both the index case and another person (5/11 households) or pet dog (2/11 households). These results suggest that transmission within the household may contribute to the community spread of ESBL- or ACBL-producing that produce extended-spectrum beta-lactamases (ESBLs) and AmpC beta-lactamases (ACBLs) are important pathogens and can cause community-acquired illnesses, such as urinary tract infections (UTIs). Fecal carriage of these resistant bacteria by companion animals may pose a risk for transmission to humans. Our work evaluated the sharing of ESBL- and ACBL-producing isolates between humans and companion animals. We found that in some households, dogs carried the same strain of ESBL-producing as the household member with a UTI. This suggests that transmission events between humans and animals (or vice versa) are likely occurring within the home environment and, therefore, the community as a whole. This is significant from a health perspective, when considering measures to minimize community transmission, and highlights that in order to manage community spread, we need to consider interventions at the household level.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1128/AEM.01613-20DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7688229PMC
November 2020

One Health Aotearoa: a transdisciplinary initiative to improve human, animal and environmental health in New Zealand.

One Health Outlook 2020 31;2(1). Epub 2020 Jan 31.

Department of Pathology and Biomedical Science, University of Otago, P.O. Box 4345, Christchurch, 8140 New Zealand.

There is increased recognition that complex health challenges at the human-animal-environmental interface require a transdisciplinary, "" approach. This philosophy is particularly pertinent in Aotearoa-New Zealand because of the country's relatively isolated island ecosystem, economic reliance on agriculture and its intensification, and existing indigenous worldview that emphasises holism and interconnectivity between humans, animals and the environment. In New Zealand, the One Health Aotearoa (OHA) alliance was established in order to better connect researchers and to address a growing number of infectious diseases challenges. The emphasis of OHA is to bring together and facilitate interactions between people from diverse disciplines, link to stakeholders and communities, and engage with policy-makers, government operational agencies, and funders, thus providing a holistic and integrative systems-thinking approach to address priority questions and achieve desired outcomes in One Health. The initial focus of OHA has been on infectious diseases, but there is increasing recognition of the potential benefits of the alliance to address broader complex issues. Greater involvement and overlap of the environmental sciences, human and animal health sciences, social science, and indigenous kaupapa Māori research is particularly critical for ensuring its success within the New Zealand context. Given the economic and cultural importance of New Zealand's "" image, a One Health approach that draws strongly on the environmental sciences makes particular sense. Furthermore, as the global environment becomes increasingly stressed by anthropogenic pressures our research may hold potential solutions for similar challenges elsewhere.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1186/s42522-020-0011-0DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7223671PMC
January 2020

Investigating the meat pathway as a source of human nontyphoidal Salmonella bloodstream infections and diarrhea in East Africa.

Clin Infect Dis 2020 Aug 10. Epub 2020 Aug 10.

Institute of Biodiversity, Animal Health, and Comparative Medicine, College of Medical, Veterinary and Life Sciences, University of Glasgow, Glasgow, Scotland, United Kingdom.

Background: Salmonella Enteritidis and Salmonella Typhimurium are major causes of bloodstream infection and diarrheal disease in East Africa. Sources of human infection, including the role of the meat pathway, are poorly understood.

Methods: We collected cattle, goat, and poultry meat pathway samples from December 2015 through August 2017 in Tanzania and isolated Salmonella using standard methods. Meat pathway isolates were compared with nontyphoidal Salmonella (NTS) isolated from persons with bloodstream infection and diarrheal disease from 2007 through 2017 from Kenya by core genome multi-locus sequence typing (cgMLST). Isolates were characterized for antimicrobial resistance, virulence genes, and diversity.

Results: We isolated NTS from 164 meat pathway samples. Of 172 human NTS isolates, 90 (52.3%) from stool and 82 (47.7%) from blood, 53 (30.8%) were Salmonella Enteritidis ST11 and 62 (36.0%) Salmonella Typhimurium ST313. We identified cgMLST clusters within Salmonella Enteritidis ST11, Salmonella Heidelberg ST15, Salmonella Typhimurium ST 19, and Salmonella II 42:r:- ST1208 that included both human and meat pathway isolates. Salmonella Typhimurium ST313 was isolated exclusively from human samples. Human and poultry isolates bore more antimicrobial resistance and virulence genes and were less diverse than isolates from other sources.

Conclusions: Our findings suggest that the meat pathway may be an important source of human infection by some clades of Salmonella Enteritidis ST11 in East Africa, but not of human Salmonella Typhimurium ST313 infection. Research is needed to systematically examine the contribution of other types of meat, animal products, produce, water, and environmental exposures to nontyphoidal Salmonella disease in East Africa.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1093/cid/ciaa1153DOI Listing
August 2020

Meat Safety in Northern Tanzania: Inspectors' and Slaughter Workers' Risk Perceptions and Management.

Front Vet Sci 2020 18;7:309. Epub 2020 Jun 18.

Institute of Biodiversity, Animal Health and Comparative Medicine, College of Medical, Veterinary and Life Sciences, University of Glasgow, Glasgow, United Kingdom.

Through a social scientific lens, this paper considers the risk perceptions and "risk-based decision-making" of two key groups in a northern Tanzanian context: (1) frontline government meat inspectors and health officers charged with ensuring that red meat sold commercially is safe for people to consume, and (2) the workers who slaughter and process cattle and red meat prior to its sale in rural butcheries. In contrast to techno-scientific understandings of disease risk and "rational" approaches to its management, this paper foregrounds the role of social, economic and institutional context in shaping the perceptions and practices around meat safety of these actors whose daily, close proximity to meat means they play a significant role in mitigating potential meat-borne disease. We show how limited resources, and a combination of scientific and local knowledge and norms result in "situated expertise" and particular forms of risk perception and practice which both enhance and compromise meat safety in different ways. Actors' shared concerns with what is visible, ensures that visibly unsafe or abnormal meat is excluded from sale, and that infrastructure and meat is kept "clean" and free of certain visible contaminants such as soil or, on occasion, feces. While such contaminants serve as a good proxy for pathogen presence, meat inspectors and especially slaughter workers were much less aware of or concerned with invisible pathogens that may compromise meat safety. The role of process and meat handling did not figure very strongly in their concerns. Microorganisms such as and , which can easily be transferred onto meat and persist in slaughter and meat sale environments, went unacknowledged. Although health officers expressed more concern with hygiene and meat handling, their influence over slaughter process and butchery operations was unclear. Ultimately, recognizing the perceptions and practices of frontline actors who engage with meat, and the ways in which social, material and institutional realities shape these, is important for understanding how decisions about risk and meat safety are made in the complexity and context of everyday life, and thus for finding effective ways to support them to further enhance their work.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.3389/fvets.2020.00309DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7314929PMC
June 2020

Meat Safety in Tanzania's Value Chain: Experiences, Explanations and Expectations in Butcheries and Eateries.

Int J Environ Res Public Health 2020 04 20;17(8). Epub 2020 Apr 20.

Institute of Development Studies, University of Sussex, Library Road, Brighton BN1 9RE, UK.

Urbanisation is associated with changes in consumption patterns and food production processes. These patterns and processes can increase or decrease the risks of outbreaks of foodborne diseases and are generally accompanied by changes in food safety policies and regulations about food handling. This affects consumers, as well as people economically engaged in the food value chain. This study looks at Tanzania's red meat value chain-which in its totality involves about one third of the population-and focuses on the knowledge, attitudes and reported practices of operators of butcheries and eateries with regards to meat safety in an urban and in a rural environment. We interviewed 64 operators about their experiences with foodborne diseases and their explanations and expectations around meat safety, with a particular emphasis on how they understood their own actions regarding food safety risks vis-à-vis regulations. We found operators of eateries emphasising their own agency in keeping meat safe, whereas operators of butcheries-whose products are more closely inspected-relied more on official inspections. Looking towards meat safety in the future, interviewees in rural areas were, relative to their urban counterparts, more optimistic, which we attribute to rural operators' shorter and relatively unmediated value chains.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.3390/ijerph17082833DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7216110PMC
April 2020

Using time-series analysis techniques to enhance the understanding of musculoskeletal injury in Thoroughbred racehorses.

Equine Vet J 2020 Sep 18;52(5):699-708. Epub 2020 Feb 18.

Centre for Applied One Health Research and Policy Advice, Jockey Club College of Veterinary Medicine and Life Sciences, City University of Hong Kong, Kowloon, Hong Kong SAR.

Background: Many racing jurisdictions monitor race-day musculoskeletal injury (MSI) but fail to evaluate injuries occurring during training. Additionally, previous risk factor analyses have failed to explore temporal trends in injury occurrence.

Objectives: To use time-series analysis techniques to identify trends, cyclicity and peaks in MSI incidence, in racehorses training and racing at the Hong Kong Jockey Club (HKJC) from July 2010 to June 2018.

Study Design: Retrospective longitudinal study.

Methods: The monthly incidence of all MSI, superficial digital flexor tendon (SDFT) injury, suspensory ligament injury and appendicular skeletal fracture occurring in training and racing were collected from veterinary records. The number of horses in training was collated monthly from trainer records. Time-series analysis techniques were used to describe trends and cyclical patterns for injury types. For each injury, incidence risks above the 90th percentile were identified as peaks in incidence.

Results: A total of 1471 injuries were recorded over eight racing seasons; 605 fractures (41.1%), 550 SDFT injuries (37.4%), and 316 suspensory ligament injuries (21.5%). Evidence of seasonality was detected in fracture incidence risk; increasing from October (median 0.25 per 1000 horses) until May (median 0.71 per 1000 horses), coinciding with the racing season (ending mid-July). Elevated incidence of MSI occurred throughout 2012; however, the greatest incidence risks of SDFT (14.8 per 1000 horses) and fracture (1.3 per 1000 horses) occurred since 2017.

Main Limitations: Monthly (opposed to daily) incidence risk of injury reduced the resolution of the data. Additionally, fracture was not described according to bone or fracture type, which may have confounded overall trends.

Conclusions: Evidence for seasonal variation in the incidence of fracture occurrence has been demonstrated. Based on using time-series techniques, further epidemiological studies, retrospectively targeting periods of high peaks in injury incidence risk could be used to aid identification of risk factors for injury.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1111/evj.13220DOI Listing
September 2020

Estimation of the burden of leptospirosis in New Zealand.

Zoonoses Public Health 2020 03 4;67(2):167-176. Epub 2019 Dec 4.

EpiCentre, School of Veterinary Science, Massey University, Palmerston North, New Zealand.

Background: Human leptospirosis mainly affects people in close occupational contact with domestic livestock and their products in New Zealand. The disease has an unquantified impact on both human health and animal production in the country. This study aimed to estimate the burden of leptospirosis in terms of disability-adjusted life years (DALYs) and cost associated with loss due to absence from work, treatment of disease, animal production loss and cost of vaccination.

Methods: Previously published studies of abattoir workers farmers, and veterinarians, reporting annual risks of influenza-like illness attributable to Leptospira infection, were used to estimate the expected number of cases in a year. The cost of lost animal production was based on results of observational studies in beef cattle, sheep and deer conducted in New Zealand.

Results: Expected median annual number of severe and mild cases of human leptospirosis was 2,025 (95% probability interval [95% PI] 1,138-3,422). Median annual DALYs were 0.42 (95% PI: 0.06-2.40) per 100,000 people for the entire population, and 15.82 (95% PI: 2.09-90.80) per 100,000 people working in at-risk occupations (i.e. abattoir workers, farmers and veterinarians). Human infection resulted in a median cost of 4.42 (95% PI: 2.04-8.62) million US dollars (USD) due to absence from work and disease treatment. Median production loss cost in beef cattle, sheep and deer was USD 7.92 (95% PI: 3.75-15.48) million, while median vaccination cost in cattle, (including dairy), sheep and deer was USD 6.15 (95% PI: 5.30-7.03) million. Total annual cost of leptospirosis plus vaccination was USD 18.80 (95% PI: 13.47-27.15) million, equivalent to USD 440,000 (95% PI: 320,000-640,000) per 100,000 people.

Conclusion: This study provides an estimate of the disease burden and cost of leptospirosis in New Zealand that could support occupational health authorities and livestock industries in assessing interventions for this disease.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1111/zph.12668DOI Listing
March 2020

Prevalence of Campylobacter and Salmonella in African food animals and meat: A systematic review and meta-analysis.

Int J Food Microbiol 2020 Feb 31;315:108382. Epub 2019 Oct 31.

Centre for International Health, Dunedin School of Medicine, University of Otago, Dunedin, New Zealand.

Background: Campylobacter and Salmonella, particularly non-typhoidal Salmonella, are important bacterial enteric pathogens of humans which are often carried asymptomatically in animal reservoirs. Bacterial foodborne infections, including those derived from meat, are associated with illness and death globally but the burden is disproportionately high in Africa. Commercial meat production is increasing and intensifying in many African countries, creating opportunities and threats for food safety.

Methods: Following Preferred Reporting Items for Systematic Reviews and Meta-analyses (PRISMA) guidelines, we searched six databases for English language studies published through June 2016, that reported Campylobacter or Salmonella carriage or infection prevalence in food animals and contamination prevalence in food animal products from African countries. A random effects meta-analysis and multivariable logistic regression were used to estimate the species-specific prevalence of Salmonella and Campylobacter and assess relationships between sample type and region and the detection or isolation of either pathogen.

Results: Seventy-three studies reporting Campylobacter and 187 studies reporting Salmonella across 27 African countries were represented. Adjusted prevalence calculations estimate Campylobacter detection in 37.7% (95% CI 31.6-44.3) of 11,828 poultry samples; 24.6% (95% CI 18.0-32.7) of 1975 pig samples; 17.8% (95% CI 12.6-24.5) of 2907 goat samples; 12.6% (95% CI 8.4-18.5) of 2382 sheep samples; and 12.3% (95% CI 9.5-15.8) of 6545 cattle samples. Salmonella were detected in 13.9% (95% CI 11.7-16.4) of 25,430 poultry samples; 13.1% (95% CI 9.3-18.3) of 5467 pig samples; 9.3% (95% CI 7.2-12.1) of 2988 camel samples; 5.3% (95% CI 4.0-6.8) of 72,292 cattle samples; 4.8% (95% CI 3.6-6.3) of 11,335 sheep samples; and 3.4% (95% CI 2.2-5.2) of 4904 goat samples. 'External' samples (e.g. hide, feathers) were significantly more likely to be contaminated by both pathogens than 'gut' (e.g. faeces, cloaca) while meat and organs were significantly less likely to be contaminated than gut samples.

Conclusions: This study demonstrated widespread prevalence of Campylobacter species and Salmonella serovars in African food animals and meat, particularly in samples of poultry and pig origin. Source attribution studies could help ascertain which food animals are contributing to human campylobacteriosis and salmonellosis and direct potential food safety interventions.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1016/j.ijfoodmicro.2019.108382DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6985902PMC
February 2020

Investigation of the validity of two Bayesian ancestral state reconstruction models for estimating Salmonella transmission during outbreaks.

PLoS One 2019 22;14(7):e0214169. Epub 2019 Jul 22.

Molecular Epidemiology and Public Health Laboratory, Massey University, Palmerston North, New Zealand.

Ancestral state reconstruction models use genetic data to characterize a group of organisms' common ancestor. These models have been applied to salmonellosis outbreaks to estimate the number of transmissions between different animal species that share similar geographical locations, with animal host as the state. However, as far as we are aware, no studies have validated these models for outbreak analysis. In this study, salmonellosis outbreaks were simulated using a stochastic Susceptible-Infected-Recovered model, and the host population and transmission parameters of these simulated outbreaks were estimated using Bayesian ancestral state reconstruction models (discrete trait analysis (DTA) and structured coalescent (SC)). These models were unable to accurately estimate the number of transmissions between the host populations or the amount of time spent in each host population. The DTA model was inaccurate because it assumed the number of isolates sampled from each host population was proportional to the number of individuals infected within each host population. The SC model was inaccurate possibly because it assumed that each host population's effective population size was constant over the course of the simulated outbreaks. This study highlights the need for phylodynamic models that can take into consideration factors that influence the characteristics and behavior of outbreaks, e.g. changing effective population sizes, variation in infectious periods, intra-population transmissions, and disproportionate sampling of infected individuals.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://journals.plos.org/plosone/article?id=10.1371/journal.pone.0214169PLOS
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6645465PMC
February 2020

Carriage and population genetics of extended spectrum β-lactamase-producing Escherichia coli in cats and dogs in New Zealand.

Vet Microbiol 2019 Jun 12;233:61-67. Epub 2019 Apr 12.

School of Veterinary Science, Massey University, Palmerston North, 4442, New Zealand. Electronic address:

The incidence of infections with extended spectrum β-lactamase producing Escherichia coli (ESBL-E) is increasing both in humans and animals. There is a paucity of data about the rate of faecal carriage of ESBL-E in pets. In this study, faecal swabs collected from 586 pets (225 cats; 361 dogs) in Auckland, New Zealand, were analysed for the presence of ESBL-E by culture, and a questionnaire was delivered to the owners. The ESBL-E were characterised and data elicited by the questionnaires were used for a multivariable analysis, to investigate the factors associated with faecal ESBL-E carriage. The prevalence of ESBL-E in faecal swabs was 6.4%. The β-lactamase genes detected in the ESBL-E were the blaCTX-M-14 (n = 2) and blaCMY-2 (n = 34). Several isolates displayed multilocus sequence types (ST) associated with human and animal infections. Multiple isolates sharing the same ST displayed different antibiograms and β-lactamase genes, reflecting horizontal gene transfer between and within ST. Variables independently associated with increased odds of ESBL-E carriage were: animal received systemic antimicrobial treatment in the six months before the sampling; presence of household members working in veterinary clinics; presence of household members travelling overseas in the six months before the sampling. We conclude that pets are colonised by ESBL-E which are genotypically similar to the bacteria found to infect humans and animals. The statistical analysis suggested a number of eco-epidemiological factors associated with ESBL-E carriage. In particular, they suggest veterinary clinics may represent hot-spots of antimicrobial resistance.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1016/j.vetmic.2019.04.015DOI Listing
June 2019

Phenotypic and Genotypic Characterization of Isolates from New Zealand with Reduced Susceptibility to Ceftriaxone.

Microb Drug Resist 2019 Sep 25;25(7):1003-1011. Epub 2019 Apr 25.

College of Health, Massey University, Palmerston North, New Zealand.

To characterize mutations in , , , and , considered target genes for antimicrobial resistance, in isolates with elevated minimum inhibitory concentrations (MICs) of ceftriaxone cultured from patients in New Zealand. Out of 28 isolates supplied by the Institute of Environmental Science and Research Limited (ESR), Porirua, New Zealand, 14 were found to show reduced susceptibility to ceftriaxone (MIC of 0.06 mg/L) according to criteria used by the ESR and the Australian Gonococcal Surveillance Programme (AGSP) when tested in our laboratory. Rates of resistance to ciprofloxacin, azithromycin, penicillin, and tetracycline were 100% (28/28), 7% (2/28), 36% (10/28), and 25% (7/28), respectively. Ten different (Penicillin binding protein 2 [PBP2]) sequences were observed. The most common mosaic M-1 resembled mosaic XXXIV, which has been associated with ceftriaxone treatment failures in other countries. Four semimosaic PBP2 sequences were observed and may be novel PBP sequences, while four out of five nonmosaic PBP2 sequences were similar to PBP2 sequences reported in Australia. Twenty-one isolates harbored mutations in all 4 genes (, , , and ), and 13 of these exhibited reduced susceptibility to ceftriaxone. Mutations in , , , and observed in this study may have contributed to reduced susceptibility to ceftriaxone among New Zealand gonococcal isolates. Over half (16/22) of mosaic sequences from the gonococcal isolates resembled XXXIV.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1089/mdr.2018.0111DOI Listing
September 2019

Epidemiological investigation of Leptospira spp. in a dairy farming enterprise after the occurrence of three human leptospirosis cases.

Zoonoses Public Health 2019 08 3;66(5):470-479. Epub 2019 Apr 3.

School of Veterinary Science, EpiCentre, Massey University, Palmerston North, New Zealand.

An epidemiological investigation was conducted in an unvaccinated dairy farming enterprise in which three workers on one of the milking herds (Herd 1) were diagnosed with leptospirosis due to serovars Hardjo (H) (n = 2) and Pomona (P) (n = 1) between January and March 2015. Blood and urine samples were collected from milking cows in Herd 1 (N = 230) and Herd 2 (N = 400), rising one- (R1, N = 125) and rising two-year-old (R2, N = 130) replacement heifers, and four pigs associated with Herd 1, in March 2015. Sera were tested using the MAT for serovars H, P, Copenhageni (C), Ballum (B) and Tarassovi (T), and urine samples were tested by qPCR. Seventy-five per cent of 109 cows in Herd 1 and 36% of 121 in Herd 2 were seropositive (≥48), predominantly to H and P, and 23% of 74 cows in Herd 1 and 1% of 90 cows in Herd 2 were qPCR positive. Fifty-five per cent of 42 R2 heifers were seropositive to T. No R1 and 17% of 42 R2 heifers were qPCR positive. Subsequently, all cattle were vaccinated for H and P, and Herds 1 and 2 were given amoxicillin. After the booster vaccination, 7% of 91 in Herd 1, 2% of 82 in Herd 2 and 11% of 38 R1 heifers (sampled as R2) were PCR positive. After the amoxicillin treatment, no cows in Herd 1 and 5% of 62 cows in Herd 2 were urine PCR positive. Calves and pigs were seropositive to H, P, C and B. Vaccination and antibiotic treatment appeared effective in reducing the risk of exposure of workers to vaccine serovars. However, evidence of non-vaccine serovars indicated that workers likely remain at risk of exposure to Leptospira.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1111/zph.12578DOI Listing
August 2019

Use of Genomics to Investigate Historical Importation of Shiga Toxin-Producing Escherichia coli Serogroup O26 and Nontoxigenic Variants into New Zealand.

Emerg Infect Dis 2019 03;25(3):489-500

Shiga toxin-producing Escherichia coli serogroup O26 is an important public health pathogen. Phylogenetic bacterial lineages in a country can be associated with the level and timing of international imports of live cattle, the main reservoir. We sequenced the genomes of 152 E. coli O26 isolates from New Zealand and compared them with 252 E. coli O26 genomes from 14 other countries. Gene variation among isolates from humans, animals, and food was strongly associated with country of origin and stx toxin profile but not isolation source. Time of origin estimates indicate serogroup O26 sequence type 21 was introduced at least 3 times into New Zealand from the 1920s to the 1980s, whereas nonvirulent O26 sequence type 29 strains were introduced during the early 2000s. New Zealand's remarkably fewer introductions of Shiga toxin-producing Escherichia coli O26 compared with other countries (such as Japan) might be related to patterns of trade in live cattle.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.3201/eid2503.180899DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6390770PMC
March 2019

Combining MALDI-TOF and genomics in the study of methicillin resistant and multidrug resistant Staphylococcus pseudintermedius in New Zealand.

Sci Rep 2019 02 4;9(1):1271. Epub 2019 Feb 4.

Molecular Epidemiology and Public Health Laboratory, Hopkirk Research Institute, Massey University, Palmerston North, New Zealand.

Staphylococcus pseudintermedius is an opportunistic and emerging zoonotic pathogen that primarily colonises the skin of dogs. Many common variants are methicillin resistant (MRSP) or multidrug resistant (MDR), and drug resistance is increasingly reported across the globe. In New Zealand, MRSP isolation remains rare in clinics. To pre-emptively inform diagnostic and antimicrobial stewardship practices, we examine isolates of S. pseudintermedius, MRSP and MDR-MRSP from New Zealand dogs using a combination of methodologies. Genetic and genomic data combined with antimicrobial susceptibility screening identify common drug-resistance profiles and their genetic determinants. We demonstrate that sensitive and specific species-level identification of S. pseudintermedius can be achieved using Bruker MALDI-TOF MS and, further, that this technique can be used to identify some common subtype variants, providing a level of categorical precision that falls somewhere between single-locus and multi-locus sequence typing. Comparative genomics analysis of global S. pseudintermedius data shows that MRSP moves frequently across the globe, but that horizontal gene transfer events resulting in the acquisition of the SCCmec cassette (responsible for beta-lactam antibiotic resistance) are infrequent. This suggests that biosecurity and surveillance in addition to antibiotic stewardship should play important roles in mitigating the risk of MRSP, especially in countries such as New Zealand where MRSP is still rare.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1038/s41598-018-37503-9DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6361924PMC
February 2019

Effects of natural infection by L. borgpetersenii serovar Hardjo type Hardjo-bovis and L. interrogans serovar Pomona, and leptospiral vaccination, on sheep growth.

Prev Vet Med 2018 Nov 17;159:196-202. Epub 2018 Sep 17.

School of Veterinary Science, Massey University, Private Bag 11222, Palmerston North 4442, New Zealand. Electronic address:

In New Zealand, up to 97% of NZ sheep flocks are seropositive to Leptospira borgpetersenii serovar Hardjo and/or Leptospira interrogans Pomona, yet vaccination is rare. This study evaluated the impact of exposure to these serovars and of vaccination on sheep growth. One third of 2260 ewe lambs on eight farms were randomly selected and vaccinated with a primary and booster bivalent Hardjo and Pomona vaccine starting at one month of age on seven farms and at around five months of age on one farm. Repeated blood samples were taken over one (n = 6 farms, bred as ewe lambs at 7-8 months of age) or two (n = 2 farms, bred as rising 2-year-old ewes) years and tested by microscopic agglutination test to assess exposure to Hardjo and Pomona. Individual weights were recorded at the same time and modelled using a multilevel linear model accounting for within-farm clustering and repeated measures. Predicted average weights were computed and compared based on the vaccination status and within the control group based on exposure status (positive for Hardjo only, Pomona only, Hardjo and Pomona and negative) for each combination of farm and weighing episode. Statistical significance of the comparison was evaluated after adjustment for multiple comparisons. There was no difference in average weight between vaccinated and control sheep before or after vaccination in any of the flocks. The comparison between sheep seropositive for either or both serovars and seronegative sheep was inconclusive, with variations of direction and magnitude of the difference between farms and weighing episodes. In the absence of an overall growth response to vaccination, widespread adoption of vaccination would unlikely yield an economic response at the industry level. However, the inconsistency observed when comparing animals based on their exposure status suggests that the actual effect of leptospirosis on growth is difficult to predict. A study of the effect on sheep reproduction is needed to fully assess the effect of vaccination on sheep production.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1016/j.prevetmed.2018.09.017DOI Listing
November 2018

Institutional gastroenteritis outbreaks and time to notify public health services.

N Z Med J 2018 07 13;131(1478):39-49. Epub 2018 Jul 13.

Molecular Epidemiology and Public Health Laboratory (mEpiLab), School of Veterinary Science, Massey University, Palmerston North.

Aim: We report a quantification and visualisation of the association between the time to notify public health service (PHS) and the duration and size of institutional gastroenteritis outbreaks, and explore the seasonality and trend of the outbreaks.

Method: Descriptive analysis was performed on institutional gastroenteritis outbreak data from a North Island PHS (1 January 2009-31 December 2014). Time-series analysis was used to explore the seasonality and trend of outbreaks. Multivariate analyses were performed to quantify the association between the time to notify PHS and the duration and size of outbreaks.

Results: One hundred and seventy-five gastroenteritis outbreaks (from 58 facilities) were included in descriptive analyses. A significant increasing trend (p=0.01) without seasonal pattern was confirmed by time-series analysis. Shorter notification time was associated with shorter duration and smaller size of outbreaks, eg, duration of outbreaks when time to notify was ≥7 days, was 3.4 days (p=0.001, 95% CI=3.1-3.7) longer than baseline time to notify (0-1 day).

Conclusion: Prompt notification to the PHS appears to be a factor associated with reduced outbreak duration and size.
View Article and Find Full Text PDF

Download full-text PDF

Source
July 2018

A systematic review of human and animal leptospirosis in the Pacific Islands reveals pathogen and reservoir diversity.

PLoS Negl Trop Dis 2018 05 14;12(5):e0006503. Epub 2018 May 14.

Australian Institute of Tropical Health and Medicine, James Cook University, Townsville, Australia.

Background: The Pacific Islands have environmental conditions highly favourable for transmission of leptospirosis, a neglected zoonosis with highest incidence in the tropics, and Oceania in particular. Recent reports confirm the emergence and outbreaks of leptospirosis in the Pacific Islands, but the epidemiology and drivers of transmission of human and animal leptospirosis are poorly documented, especially in the more isolated and less developed islands.

Methodology/principal Findings: We conducted a systematic review of human and animal leptospirosis within 25 Pacific Islands (PIs) in Polynesia, Melanesia, Micronesia, as well as Easter Island and Hawaii. We performed a literature search using four international databases for articles published between January 1947 and June 2017. We further included grey literature available on the internet. We identified 148 studies describing leptospirosis epidemiology, but the number of studies varied significantly between PIs. No data were available from four PIs. Human leptospirosis has been reported from 13 PIs, with 63% of all studies conducted in Hawaii, French Polynesia and New Caledonia. Animal leptospirosis has been investigated in 19 PIs and from 14 host species, mainly pigs (18% of studies), cattle (16%) and dogs (11%). Only 13 studies provided information on both human and animal leptospirosis from the same location. Serology results were highly diverse in the region, both in humans and animals.

Conclusions/significance: Our study suggests that, as in other tropical regions, leptospirosis is widespread in the PIs while showing some epidemiological heterogeneity. Data are scarce or absent from many PIs. Rodents, cattle, pigs and dogs are all likely to be important carriers, but the relative importance of each animal species in human infection needs to be clarified. Epidemiological surveys with appropriate sampling design, pathogen typing and data analysis are needed to improve our understanding of transmission patterns and to develop effective intervention strategies.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1371/journal.pntd.0006503DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5967813PMC
May 2018

Molecular Epidemiology of Shiga Toxin-Producing Escherichia coli (STEC) on New Zealand Dairy Farms: Application of a Culture-Independent Assay and Whole-Genome Sequencing.

Appl Environ Microbiol 2018 07 2;84(14). Epub 2018 Jul 2.

EpiLab, Massey University, Palmerston North, New Zealand.

New Zealand has a relatively high incidence of human cases of Shiga toxin-producing (STEC), with 8.9 STEC cases per 100,000 people reported in 2016. Previous research showed living near cattle and contact with cattle feces as significant risk factors for STEC infections in humans in New Zealand, but infection was not linked to food-associated factors. During the 2014 spring calving season, a random, stratified, cross-sectional study of dairy farms ( = 102) in six regions across New Zealand assessed the prevalence of the "Top 7" STEC bacteria (serogroups O157, O26, O45, O103, O111, O121, and O145) in young calves ( = 1,508), using a culture-independent diagnostic test (PCR/MALDI-TOF). Twenty percent (306/1,508) of calves on 75% (76/102) of dairy farms were positive for at least one of the "Top 7" STEC bacteria. STEC carriage by calves was associated with environmental factors, increased calf age, region, and increased number of calves in a shared calf pen. The intraclass correlation coefficient (ρ) indicated strong clustering of "Top 7" STEC-positive calves for O157, O26, and O45 serogroups within the same pens and farms, indicating that if one calf was positive, others in the same environment were likely to be positive as well. This finding was further evaluated with whole-genome sequencing, which indicated that a single O26 clonal strain could be found in calves in the same pen or farm, but different strains existed on different farms. This study provides evidence that would be useful for designing on-farm interventions to reduce direct and indirect human exposure to STEC bacteria. Cattle are asymptomatic carriers of Shiga toxin-producing (STEC) bacteria that can cause bloody diarrhea and kidney failure in humans if ingested. New Zealand has relatively high numbers of STEC cases, and contact with cattle feces and living near cattle are risk factors for human infection. This study assessed the national prevalence of STEC in young dairy cattle by randomly selecting 102 farms throughout New Zealand. The study used a molecular laboratory method that has relatively high sensitivity and specificity compared to traditional methods. "Top 7" STEC was found in 20% of calves on 75% of the farms studied, indicating widespread prevalence across the country. By examining the risk factors associated with calf carriage, potential interventions that could decrease the prevalence of "Top 7" STEC bacteria at the farm level were identified, which could benefit both public health and food safety.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1128/AEM.00481-18DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6029106PMC
July 2018

A Bayesian spatio-temporal framework to identify outbreaks and examine environmental and social risk factors for infectious diseases monitored by routine surveillance.

Spat Spatiotemporal Epidemiol 2018 06 2;25:39-48. Epub 2017 Nov 2.

mEpiLab, Infectious Disease Research Centre, Hopkirk Research Institute, Massey University, Palmerston North, New Zealand.

Spatio-temporal disease patterns can provide clues to etiological pathways, but can be complex to model. Using a flexible Bayesian hierarchical framework, we identify previously undetected space-time clusters and environmental and socio-demographic risk factors for reported giardiasis and cryptosporidiosis at the New Zealand small area level. For giardiasis, there was no seasonal pattern in outbreak probability and an inverse association with density of dairy cattle (β^ = -0.09, Incidence Risk Ratio (IRR) 0.90 (95% CI 0.84, 0.97) per 1 log increase in cattle/km). In dairy farming areas, cryptosporidiosis outbreaks were observed in spring. Reported cryptosporidiosis was positively associated with dairy cattle density: β^ = 0.12, IRR 1.13 (95% CI 1.05, 1.21) per 1 log increase in cattle/km and inversely associated with weekly average temperature: β^ = -0.07, IRR 0.92 (95% CI 0.87, 0.98) per 4 °C increase. This framework can be generalized to determine the potential drivers of sporadic cases and latent outbreaks of infectious diseases of public health importance.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1016/j.sste.2017.10.004DOI Listing
June 2018

Effects of natural infection by L. borgpetersenii serovar Hardjo type Hardjo-bovis, L. interrogans serovar Pomona and leptospiral vaccination on sheep reproduction.

Theriogenology 2018 Jul 22;114:126-135. Epub 2018 Mar 22.

School of Veterinary Science, Massey University, Private Bag 11222, Palmerston North 4442, New Zealand. Electronic address:

Most New Zealand sheep flocks are seropositive to Leptospira serovars Hardjo and/or Pomona, yet vaccination is rare. This study evaluated the impact of exposure to these serovars and of vaccination, on primiparous one- (P1) and two-year-old (P2) sheep reproduction outcomes. The study was designed as a split-flock vaccination trial, with a third of the animals vaccinated starting at one month of age. Reproduction outcomes were the proportion of bred P1 (7 months old) and as P2 (19 months old) scanned pregnant, the proportion of pregnant ewes rearing a lamb to tail docking and the proportion of docked lambs that were weaned. Odds ratios and their 95% confidence intervals were calculated to compare reproductive performance between vaccinated and control sheep, and within the control group, between seropositive and seronegative sheep. Odds ratios (OR) were also calculated to assess the relationship between vaccination and loss to follow-up. There was no difference in pregnancy and docking rates between vaccinated and control sheep, or between seropositive and seronegative sheep. P1 with a Hardjo titre ≥1536 were significantly less likely (OR = 0.41, 95%CI = 0.19-0.93) to keep a lamb between docking and weaning than P1 with both Hardjo and Pomona titres <1536, for an observed difference in weaning rate of up to 22.6% points on one farm. A reduction of weaning rates in 2-tooths seropositive for Pomona alone and both Hardjo and Pomona was observed but this was non-significant, possibly because of a lack of power. No difference in weaning rate was observed between vaccinated and control P1 or P2. On one farm vaccinated P1 were less likely to be lost to follow-up (OR = 0.27, 95% CI 0.08 to 0.95) between breeding and weaning. Comparing reproductive performance of vaccinated and control sheep revealed no significant difference. However, comparing exposed and non-exposed ewes revealed a possible adverse effect of Leptospira on weaning rates. This suggests that a full vaccination program may result in an improvement of reproductive outcomes, possibly by providing herd immunity.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1016/j.theriogenology.2018.03.022DOI Listing
July 2018

A road map for leptospirosis research and health policies based on country needs in Latin America.

Rev Panam Salud Publica 2018 Feb 19;41:e131. Epub 2018 Feb 19.

World Health Organization, Geneva, Switzerland.

This report summarizes the presentations, discussions and the recommendations coming from the Oswaldo Cruz Institute/FIOCRUZ International Workshop for Leptospirosis Research Based on Country Needs and the 5th Global Leptospirosis Environmental Action Network meeting, which was held in the city of Rio de Janeiro, Brazil, 10-12 November 2015. The event focused on health policy and worked to develop a road map as a consensus document to help guide decision-making by policymakers, funding bodies, and health care professionals. The direction that leptospirosis research should take in the coming years was emphasized, taking into account the needs of countries of Latin America, as well as experiences from other world regions, as provided by international experts. The operational concepts of "One Health" and translational research underlaid the discussions and the resulting recommendations. Despite the wide geographic distribution of leptospirosis and its impact in terms of incidence, morbidity, and mortality, leptospirosis is not yet considered a "tool-ready" disease for global initiatives. Surveillance programs need new tools and strategies for early detection, prevention, and follow-up. The major recommendations developed at the Rio meeting cover both health policy and research. The health policy recommendations should be taken into account by decisionmakers, government officials, and the Pan American Health Organization. The priorities for research, technological development, and innovation should be considered by research institutions, universities, and stakeholders.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6645167PMC
February 2018

Food Safety, Health Management, and Biosecurity Characteristics of Poultry Farms in Arusha City, Northern Tanzania, Along a Gradient of Intensification.

East Afr Health Res J 2018 23;2(2):168-180. Epub 2018 Nov 23.

Institute of Biodiversity, Animal Health & Comparative Medicine, College of Medical, Veterinary and Life Sciences, University of Glasgow, Glasgow, UK.

Background: With the growth, urbanisation, and changing consumption patterns of Tanzania's human population, new livestock production systems are emerging. Intensification of poultry production may result in opportunities and threats for food safety, such as improved awareness of biosecurity or increasing prevalence of foodborne pathogens including nontyphoidal or spp. We conducted a semiquantitative analysis of poultry production systems in northern Tanzania, with emphasis on biosecurity, health management practices, and prevalence of foodborne pathogens, to gain insight into potential associations between intensification and food safety.

Methods: Interviews were conducted with managers of 40 poultry farms, with equal representation of 4 production systems (extensive, semi-intensive, or intensive production with indigenous chickens, and broiler farming). Per farm, up to 10 birds (total, 386) were tested for cloacal shedding of nontyphoidal , with a subset of farms tested for . Data were analysed using univariate statistics, and results were discussed during feedback workshops with participating farmers and extension officers.

Results: Clear differences existed between farm types with regard to implementation of biosecurity and health management practices and use of extension services. By contrast, prevalence of foodborne pathogens (6 of 40 farms or 15% for nontyphoidal and 13 of 26 farms or 50% for spp.) was not farm-type specific, indicating that it is driven by other factors. Across farming systems, knowledge and awareness of the presence of antimicrobials in poultry feed and the need to abide by post-treatment withdrawal times were limited, as was access to impartial professional advice regarding treatment.

Conclusion: Different control measures may be needed to protect poultry health compared to public health, and improvements in information provision may be needed for both.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.24248/EAHRJ-D-18-00034DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8279270PMC
November 2018

Long-term Colonization by Campylobacter jejuni Within a Human Host: Evolution, Antimicrobial Resistance, and Adaptation.

J Infect Dis 2017 12;217(1):103-111

mEpiLab, Hopkirk Research Institute, Massey University, Palmerston North, New Zealand.

Background: Campylobacteriosis is inflammation of the gastrointestinal tract as a result of Campylobacter infection. Most campylobacteriosis cases are acute and self-limiting, with Campylobacter excretion ceasing a few weeks after symptoms cease. We identified a patient with fecal specimens positive for Campylobacter jejuni (ST45) intermittently during a 10-year period.

Methods: Sixteen Campylobacter isolates were collected from the patient during 2006-2016. The isolates' genomes were sequenced to determine their relatedness, and their antimicrobial susceptibility patterns and motility were measured to determine the effects of antibiotic therapy and long-term excretion on the Campylobacter population.

Results: Phylogenetic analyses estimated that the isolates shared a date of common ancestor between 1998 and 2006, coinciding with the onset of symptoms for the patient. Genomic analysis identified selection for changes in motility, and antimicrobial susceptibility testing suggested that the Campylobacter population developed resistance to several antibiotics coinciding with periods of antibiotic therapy.

Conclusions: The patient was consistently colonized with organisms from a Campylobacter population that adapted to the internal environment of the patient. Genomic and phylogenetic analyses can give insight into a patient's infection history and the effect of antimicrobial treatment on Campylobacter populations in this unusual situation of long-term colonization of an individual.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1093/infdis/jix561DOI Listing
December 2017

A Retrospective Cohort Study of an Outbreak of Cryptosporidiosis among Veterinary Students.

Vet Sci 2017 May 24;4(2). Epub 2017 May 24.

Institute of Veterinary, Animal & Biomedical Sciences, Massey University, Private Bag, Palmerston North 4442, New Zealand.

An outbreak of gastrointestinal illness occurred among a cohort of 56 veterinary technology and 100 veterinary science students at Massey University over an eight-week period in 2013. This coincided with calving in New Zealand's seasonal dairy farming system and a time when calves with diarrhoea are commonly seen by veterinarians. Laboratory and epidemiological investigations were instigated by MidCentral Public Health Service (MCPHS) in conjunction with the Institute of Veterinary, Animal and Biomedical Sciences (IVABS) at Massey University. Eighty students responded to a questionnaire of which 19 met the case definition, a 24% attack rate. Faecal specimens from seven students contained oocysts and A18G3R1 was identified from one of the specimens. The inferred median incubation period was five days (range 1-12 days). All of the cases were self-limiting, characterized by diarrhoea, abdominal cramps, and in some cases vomiting, headache, and fever. Having contact with calves with diarrhoea was significantly associated with increased adjusted odds of being a case (OR 10.61, 95% CI 1.87-108.29 for one week of contact; OR 55.05, 95% CI 3.80-1931.18 for two weeks of contact). Outbreaks of cryptosporidiosis had occurred previously among veterinary students at Massey University, but the extremely high infectivity of resulted in student illness despite enhanced hygiene precautions.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.3390/vetsci4020029DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5606607PMC
May 2017
-->