Department of Health Services, Ministry of Health, Government of Nepal, Kathmandu, Nepal.
Background: Leptospirosis is a re-emerging zoonotic disease caused by pathogenic strains of bacteria belonging to genus Leptospira whose symptoms can range from mild clinical manifestations to a severe life threatening illness. This disease may be under-recognized in resource poor settings like Nepal where many clinical laboratories lack appropriate equipment, technology and personnel for proper diagnosis.
Methods: We used IgM ELISA to estimate the sero-prevalence of leptospirosis in a group of febrile patients in a western region of Nepal. Read More
Glob Pediatr Health 2017 25;4:2333794X17726941. Epub 2017 Aug 25.
KK Women's and Children's Hospital, Singapore, Singapore.
This is a case report of a 12-year-old returned traveler with typhoid and scrub typhus coinfection. The diagnosis of typhoid was made early with blood cultures and Widal Weil Felix serology. Persistent fever despite appropriate antibiotics for typhoid fever prompted a search for concomitant infection, which led to the diagnosis of scrub typhus confirmed by Orientia tsutsugamushi serology. Read More
aDepartment for Interventions in Health Care Facilities, Hellenic Center for Disease Control and Prevention, Athens, Greece; bFirst Department of Pediatrics, University of Athens Medical School, Aghia Sophia Children's Hospital, Athens, Greece.
Background: There are few publications focusing on vaccination and malaria chemoprophylaxis in adolescent travelers. We assessed pre-travel vaccinations and malaria chemoprophylaxis of adolescents 12-18 old traveling from Greece to international destinations.
Methods: We prospectively studied 239 adolescents 12-18 years old during 2008-2016. Read More
Salmonella enterica serovar Typhi (S. Typhi), the causative agent of the typhoid fever, is a pathogen of great public health importance. Typhoid vaccines have the potential to be cost-effective measures towards combating this disease, yet the antigens triggering host protective immune responses are largely unknown. Read More
Salmonella enterica subspecies enterica serovar Typhi is the aetiological agent of typhoid or enteric fever. In a subset of individuals, S. Typhi colonizes the gallbladder causing an asymptomatic chronic infection. Read More
Introduction: Typhoid and paratyphoid fever remain a global health problem, which - in non-endemic countries - are mainly seen in travelers, particularly in VFRs (visiting friends and relatives), with occasional local outbreaks occurring. A rise in anti-microbial resistance emphasizes the role of preventive measures, especially vaccinations against typhoid and paratyphoid fever for travelers visiting endemic countries. Areas covered: This state-of-the-art review recapitulates the epidemiology and mechanisms of disease of typhoid and paratyphoid fever, depicts the perspective of non-endemic countries and travelers (VFRs), and collectively presents current European recommendations for typhoid fever vaccination. Read More
Front Cell Infect Microbiol 2017 9;7:348. Epub 2017 Aug 9.
Department of Pathology, University of CambridgeCambridge, United Kingdom.
Salmonella causes disease in humans and animals ranging from mild self-limiting gastroenteritis to potentially life-threatening typhoid fever. Salmonellosis remains a considerable cause of morbidity and mortality globally, and hence imposes a huge socio-economic burden worldwide. A key property of all pathogenic Salmonella strains is the ability to invade non-phagocytic host cells. Read More
We report on the first survey of hypertension in undergraduates in Sierra Leone. Levels of hypertension (12%) and obesity (4%) appear low compared to the general population but given the rapid increase of both and the expectation that many graduates will enter the formal employment sector and a sedentary lifestyle, there is still cause for concern. We measured their BMI (body mass index) and used a questionnaire to investigate demographic and lifestyle choices. Read More
Risk, severity, and outcome of infection depend on the interplay of pathogen virulence and host susceptibility. Systematic identification of genetic susceptibility to infection is being undertaken through genome-wide association studies, but how to expeditiously move from genetic differences to functional mechanisms is unclear. Here, we use genetic association of molecular, cellular, and human disease traits and experimental validation to demonstrate that genetic variation affects expression of VAC14, a phosphoinositide-regulating protein, to influence susceptibility to Salmonella enterica serovar Typhi (S Typhi) infection. Read More
Purpose: Typhoid fever caused by Salmonella enterica serovar Typhi has contributed to the global public health burden, particularly in developing countries. In this study, an S. Typhi ghost was developed and its capacity as a vaccine candidate against typhoid fever was assessed. Read More
Introduction: Typhoid fever is an endemic disease in India against which many antibiotics are available. In the recent times, emerging resistance to traditional antibiotics, such as Ampicillin, Chloramphenicol and Trimethoprim/sulfamethoxazole, Azithro-mycin and third generation Cephalosporins are being reported and increasingly being used in the treatment of invasive Salmonella infections. However, the latter two drugs have been reported with occasional clinical failures. Read More
Introduction: Typhoid fever remains a scourge of humanity, especially in developing and under-developed countries due to poor sanitation and food hygiene. Diagnostic methods available for detection of this disease are not satisfactory due to a lack of sensitive, specific, rapid and convenient diagnostic test kits available in the market.
Aim: To evaluate the feasibility of a Dot-EIA method for Ig-class specific salivary antibody detection for diagnosis of typhoid fever. Read More
Introduction: Spotted Fever Rickettsiosis (SFR), an acute febrile illness caused by Rickettsia rickettsii, R. conorii and R. akari which is associated with considerable morbidity and mortality. Read More
We studied food and water-borne diseases (FWDs), sexually transmitted diseases (STDs), vector-borne diseases (VBDs) and diseases vaccinated against in the Swedish childhood vaccination programme among Swedish international travellers, in order to identify countries associated with a high number of infections. We used the national database for notifiable infections to estimate the number of FWDs (campylobacteriosis, salmonellosis, giardiasis, shigellosis, EHEC, Entamoeba histolytica, yersinosis, hepatitis A, paratyphoid fever, typhoid fever, hepatitis E, listeriosis, cholera), STIs (chlamydia, gonorrhoea and acute hepatitis B), VBDs (dengue fever, malaria, West Nile fever, Japanese encephalitis and yellow fever) and diseases vaccinated against in the Swedish childhood vaccination programme (pertussis, measles, mumps, rubella, diphtheria) acquired abroad 2009-2013. We obtained number and duration of trips to each country from a database that monthly collects travel data from a randomly selected proportion of the Swedish population. Read More
Background: Typhoid fever, caused by the intracellular pathogen Salmonella (S.) enterica serovar Typhi, remains a major cause of morbidity and mortality worldwide. Granzymes are serine proteases promoting cytotoxic lymphocytes mediated eradication of intracellular pathogens via the induction of cell death and which can also play a role in inflammation. Read More
Despite their high degree of genomic similarity, different Salmonella enterica serovars are often associated with very different clinical presentations. In humans, for example, the typhoidal S. enterica serovar Typhi causes typhoid fever, a life-threatening systemic disease. Read More
Gram negative enteric bacteria, Salmonella enterica serovar Typhi (S. Typhi), the etiological agent of typhoid fever is a major public health problem in developing countries. While a permanent solution to the problem would require improved sanitation, food and water hygiene, controlling the infection by vaccination is urgently required due to the emergence of multidrug resistant strains in multiple countries. Read More
More than a century ago, infections by Salmonella were already associated with foodborne enteric diseases with high morbidity in humans and cattle. Intestinal inflammation and diarrhea are hallmarks of infections caused by nontyphoidal Salmonella serovars, and these pathologies facilitate pathogen transmission to the environment. In those early times, physicians and microbiologists also realized that typhoid and paratyphoid fever caused by some Salmonella serovars could be transmitted by "carriers," individuals outwardly healthy or at most suffering from some minor chronic complaint. Read More
Fiji, an upper-middle income state in the Pacific Ocean, has experienced an increase in confirmed case notifications of enteric fever caused by Salmonella enterica serovar Typhi (S. Typhi). To characterize the epidemiology of typhoid exposure, we conducted a cross-sectional sero-epidemiological survey measuring IgG against the Vi antigen of S. Read More
J Med Microbiol 2017 Jul 19;66(7):937-945. Epub 2017 Jul 19.
1Centre for Enteric Diseases, National Institute for Communicable Diseases, a division of the National Health Laboratory Service, Johannesburg, South Africa 2Faculty of Health Sciences, University of the Witwatersrand, Johannesburg, South Africa.
Purpose: Molecular epidemiological investigations of the highly clonal Salmonella enterica subspecies enterica serovar Typhi (S. Typhi) are important in outbreak detection and in tracking disease transmission. In this study, we developed and evaluated a multiple-locus variable-number tandem-repeats (VNTR) analysis (MLVA) assay for characterization of S. Read More
Typhoid and paratyphoid are two common enteric infectious diseases with serious gastrointestinal symptoms. Data was collected of the registered cases in Zhejiang Province from 2005 to 2015. The epidemiological characteristics were investigated and high-risk regions were detected with descriptive epidemiological methods and in-depth spatio-temporal statistics. Read More
Aim: This study aimed to report medicinal plants that are likely to be used in the control of salmonellosis.
Materials And Methods: A cross-sectional study was conducted in Southern Benin. Semi-structured questionnaires were administered to 150 farmers and 100 traditional therapists in seven high municipalities. Read More
Background: Dengue (DEN) is being recognised as the world's major emerging tropical disease. Clinically, DEN may resemble other infections such as malaria, leptospirosis, and typhoid, and thus, laboratory investigations are required for definitive diagnosis. Secondary DEN infection, caused most often by dengue virus (DENV) serotypes 2 and 3, is known to present with severe disease manifestations. Read More
Molecular subtyping, and recently DNA sequencing based methods, which are commonly used for discriminating Salmonella enterica serovar Typhi (S. Typhi) isolates, leads to improved molecular epidemiological investigations for prevention and control of typhoid fever. We included S. Read More
Introduction: Invasive infections caused by Salmonella enterica serovar Typhi and Paratyphi A are estimated to account for 12-27 million febrile illness episodes worldwide annually. Determining the true burden of typhoidal Salmonellae infections is hindered by lack of population-based studies and adequate laboratory diagnostics.The Strategic Typhoid alliance across Africa and Asia study takes a systematic approach to measuring the age-stratified burden of clinical and subclinical disease caused by typhoidal Salmonellae infections at three high-incidence urban sites in Africa and Asia. Read More
Typhoid fever is a very common illness in developing countries. Patients most often present with a history of fever, vomiting, anorexia, abdominal pain, etc. Rarely there is hepatic involvement due to the disease process. Read More
Unlike many of the nontyphoidal Salmonella serovars such as S. Typhimurium that cause restricted gastroenteritis, Salmonella Typhi is unique in that it causes life-threatening typhoid fever in humans. Despite the vast difference in disease outcomes that S. Read More
Background: Ebola virus disease (EVD) can be clinically severe and highly fatal, making surveillance efforts for early disease detection of paramount importance. In areas with limited access to laboratory testing, the Integrated Disease Surveillance and Response (IDSR) strategy in the Democratic Republic of Congo (DRC) may be a vital tool in improving outbreak response.
Methods: Using DRC IDSR data from the nation's four EVD outbreak periods from 2007-2014, we assessed trends of Viral Hemorrhagic Fever (VHF) and EVD differential diagnoses reportable through IDSR. Read More
Aims: Recently, the cefixime-ofloxacin combination is approved by Drug Controller General of India to treat typhoid fever. We sought to evaluate the antimicrobial activity of cefixime-ofloxacin combination against Salmonella Typhi.
Methods And Results: A total of 283 nonduplicate S. Read More
Objective: Through analyzing the surveillance data on typhoid fever and paratyphoid fever in 2015 to understand the related epidemiological features and most possible clustering areas of high incidence. Methods: Individual data was collected from the passive surveillance program and analyzed by descriptive statistic method. Characteristics on seasonal, regional and distribution of the diseases were described. Read More
Improved serodiagnostic tests for typhoid fever (TF) are needed for surveillance, to facilitate patient management, curb antibiotic resistance, and inform public health programs. To address this need, IgA, IgM and IgG ELISAs using Salmonella enterica serovar Typhi (S. Typhi) lipopolysaccharide (LPS) and hemolysin E (t1477) protein were conducted on 86 Nigerian pediatric TF and 29 non-typhoidal Salmonella (NTS) cases, 178 culture-negative febrile cases, 28 "other" (i. Read More
Human typhoid fever caused by Salmonella Typhi still poses a severe global disease burden in developing countries despite the availability of commercial vaccines. In this study, we constructed a non-living S. Typhi Ty21a vaccine candidate by employing a lambda (λ) phage-derived holin-endolysin system to efficiently construct bacterial ghosts. Read More
Salmonella enterica serovar Typhi causes the systemic disease typhoid fever. After ingestion, it adheres to and invades the host epithelium while evading the host innate immune response, causing little if any inflammation. Conversely, Salmonella enterica serovar Typhimurium causes gastroenteritis in humans and thrives in the inflamed gut. Read More
Salmonella typhi is responsible for typhoid fever, which is a serious health threat in developing countries. As a virulent factor of Salmonella typhi, the purified Vi polysaccharide (Vi PS) has become an effective vaccine to combat typhoid fever. The chemical synthesis can provide homogeneous and well-defined molecules for the development of Vi-based vaccines. Read More
Background: Approximately the 8% of travelers requires medical care, with the diagnosis of a vaccine-preventable disease. The aim of our study was to analyze the socio-demographic, health and travel characteristics of the Italian international travelers.
Methods: We conducted a cross sectional study from January 2015 to June 2016, at the Travel Medicine Clinic of Siena, asking the doctor to interview patients who attended the Clinic, recording socio-demographic and travel information, malaria prophylaxis, vaccinations. Read More
PagN is a highly immunogenic 27-kDa outer membrane adhesin present in Salmonella Typhi. It plays a major role in the pathogenesis of typhoid fever and has emerged as a strong vaccine candidate. In this report, we predict the three-dimensional structure of PagN and describe the conformational dynamics associated with its four extracellular loops based on two 100-ns molecular dynamics simulations at 300 and 310 K. Read More
Salmonella enterica subspecies enterica includes several serovars infecting both humans and other animals and leading to typhoid fever or gastroenteritis. The high prevalence of associated morbidity and mortality, together with an increased emergence of multidrug-resistant strains, is a current global health issue that has prompted the development of vaccination strategies that confer protection against most serovars. Currently available systemic vaccine approaches have major limitations, including a reduced effectiveness in young children and a lack of cross-protection among different strains. Read More
A Typhoid Conjugate Vaccine (TCV) is expected to acquire WHO prequalification soon, which will pave the way for its use in many low- and middle-income countries where typhoid fever is endemic. Thus it is critical to forecast future vaccine demand to ensure supply meets demand, and to facilitate vaccine policy and introduction planning. We forecasted introduction dates for countries based on specific criteria and estimated vaccine demand by year for defined vaccination strategies in 2 scenarios: rapid vaccine introduction and slow vaccine introduction. Read More
Salmonella Typhi cause a broad spectrum of human illnesses like gastroenteritis, typhoid fever, and bacteremia. It has also been recognized as a causative organism of osteomyelitis for more than a century but the incidence appears to be uncommon. Microbiological workup plays important role in the diagnosis of Typhoid spondylodiscitis as most of the time it mimics tuberculosis and misguide the clinician, especially in the developing world. Read More
Surface-modified diatom substrates are employed for the development of immunocomplex-based optical biosensor for diagnosis of typhoid. Biosensor has been prepared by covalent immobilization of Salmonella typhi antibody onto the crosslinked diatom substrates via glutaraldehyde. Photoluminescent (PL) studies revealed good specificity and ability of conjugated diatom substrates to distinguish complementary (S. Read More
Background: Afghanistan's public health system was neglected during decades of military and civil conflict, and trends in infectious disease occurrence remain poorly characterized. This study examines cyclical and long-term trends of six vaccine-preventable diseases: pneumonia, diarrhea, meningitis, typhoid, measles, and acute viral hepatitis.
Methods: Using weekly data collected between 2009 and 2015 through Afghanistan's Disease Early Warning System, we calculated monthly case counts, and fit a Poisson regression with a Fourier transformation for seasonal cycles and dummy variables for year. Read More
Background: The aim of this study was to examine biochemical investigations not routinely performed prior to emergency laparotomy in patients at Queen Elizabeth Central Hospital, a low-resource public hospital in Blantyre, Malawi.
Methods: A prospective cross-sectional study of adults (N = 15) needing emergency laparotomy over a 4-week period were studied at Queen Elizabeth Central Hospital. Biochemical investigations, not routinely performed for economic reasons, were performed preoperatively; these included sodium, potassium, chloride, carbon dioxide, urea, and calcium levels. Read More
J Infect 2017 Aug 25;75(2):104-114. Epub 2017 May 25.
The Hospital for Tropical Diseases, Wellcome Trust Major Overseas Programme, Oxford University Clinical Research Unit, Ho Chi Minh City, Viet Nam; Centre for Tropical Medicine and Global Health, Oxford University, Oxford, United Kingdom; The Department of Medicine, University of Cambridge, Cambridge, United Kingdom. Electronic address:
Objectives: The diagnosis of typhoid fever is a challenge. Aiming to develop a typhoid diagnostic we measured antibody responses against Salmonella Typhi (S. Typhi) protein antigens and the Vi polysaccharide in a cohort of Bangladeshi febrile patients. Read More
Background: Antimicrobials are drugs that were once lifesavers and mainly curative. Nowadays their value is increasingly under pressure because of the rapid and worldwide emergence of antimicrobial resistance, which, in low-resource settings, frequently occurs in microorganisms that are likely to be transmitted in the community.
Methods: This was a cross-sectional pilot study including 102 households within the 10th Health and Demographic Surveillance System round in Dande, Bengo Province, Angola. Read More
A nested multiplex polymerase chain reaction (PCR) based diagnosis was developed for the detection of virulent Salmonella typhi in the blood specimens from patients suspected for typhoid fever. After the Widal test, two pairs of primers were used for the detection of flagellin gene (fliC) of S. typhi. Read More
Background: Differentiating both typhoid (Salmonella Typhi) and paratyphoid (Salmonella Paratyphi A) infection from other causes of fever in endemic areas is a diagnostic challenge. Although commercial point-of-care rapid diagnostic tests (RDTs) for enteric fever are available as alternatives to the current reference standard test of blood or bone marrow culture, or to the widely used Widal Test, their diagnostic accuracy is unclear. If accurate, they could potentially replace blood culture as the World Health Organization (WHO)-recommended main diagnostic test for enteric fever. Read More