Publications by authors named "Emily E Ricotta"

14 Publications

  • Page 1 of 1

Chronic diseases: Perceptions about Covid-19 risk and vaccination.

medRxiv 2021 Mar 24. Epub 2021 Mar 24.

Background: Individuals with chronic disease may be at higher risk of dying from COVID-19, yet no association has been established between chronic illness and COVID-19 risk perception, engagement with nonpharmaceutical interventions (NPIs), or vaccine acceptance.

Methods: We surveyed US residents who self-reported a chronic respiratory or autoimmune disease in February 2021. Respondents reported beliefs about the risk of COVID-19 to personal and public health, adoption and support of NPIs, willingness to be vaccinated against COVID-19, and reasons for vaccination willingness. We evaluated the association between disease status and COVID-19 behaviors or attitudes, adjusting for demographic and political factors.

Results: Compared to healthy controls, chronic disease was associated with increased belief that COVID-19 was a personal (Respiratory = 0.12, 95% confidence interval (CI) = 0.10 - 0.15; Autoimmune = 0.11, CI = 0.08 - 0.14) and public threat (Respiratory = 0.04, CI = 0.02 - 0.06; Autoimmune = 0.03, CI = 0.01 - 0.06), and support for NPIs. Chronic respiratory disease was associated with willingness to be vaccinated (0.6, CI = 0.05 - 0.09). Personal protection was associated with vaccination (Respiratory = 1.08, CI = 1.03 - 1.13; Autoimmune = 1.06, CI = 1.01 - 1.11). Autoimmune disease was associated with fear of a bad vaccine reaction (1.22, CI = 1.06 - 1.41) among those unwilling to be vaccinated.

Conclusions: In the US, chronic disease status is significantly related to risk perceptions of COVID, support of personal and community risk mitigation measures, and willingness to be vaccinated.
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http://dx.doi.org/10.1101/2021.03.17.21253760DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8010746PMC
March 2021

Extrapulmonary Nontuberculous Mycobacteria Infections in Hospitalized Patients, United States, 2009-2014.

Emerg Infect Dis 2021 Mar;27(3):845-852

Nontuberculous mycobacteria (NTM) cause pulmonary and extrapulmonary infections in susceptible persons. To characterize the epidemiology of skin and soft tissue (SST) and disseminated extrapulmonary infections caused by NTM in the United States, we used a large electronic health record database to examine clinical, demographic, and laboratory data for hospitalized patients with NTM isolated from extrapulmonary sources during 2009-2014. Using all unique inpatients as the denominator, we estimated prevalence and summarized cases by key characteristics. Of 9,196,147 inpatients, 831 had confirmed extrapulmonary NTM. The 6-year prevalence was 11 cases/100,000 inpatients; source-specific prevalence was 4.4 SST infections/100,000 inpatients and 3.7 disseminated infections/100,000 inpatients. NTM species varied across geographic region; rapidly growing NTM were most prevalent in southern states. Infection with Mycobacterium avium complex was more common among patients with concurrent HIV and fungal infection, a relevant finding because treatment is more effective for M. avium complex than for other NTM infections.
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http://dx.doi.org/10.3201/eid2703.201087DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7920686PMC
March 2021

An immune-based biomarker signature is associated with mortality in COVID-19 patients.

JCI Insight 2021 01 11;6(1). Epub 2021 Jan 11.

Laboratory of Clinical Immunology and Microbiology, National Institute of Allergy and Infectious Diseases (NIAID), National Institutes of Health (NIH), Bethesda, Maryland, USA.

Immune and inflammatory responses to severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) contribute to disease severity of coronavirus disease 2019 (COVID-19). However, the utility of specific immune-based biomarkers to predict clinical outcome remains elusive. Here, we analyzed levels of 66 soluble biomarkers in 175 Italian patients with COVID-19 ranging from mild/moderate to critical severity and assessed type I IFN-, type II IFN-, and NF-κB-dependent whole-blood transcriptional signatures. A broad inflammatory signature was observed, implicating activation of various immune and nonhematopoietic cell subsets. Discordance between IFN-α2a protein and IFNA2 transcript levels in blood suggests that type I IFNs during COVID-19 may be primarily produced by tissue-resident cells. Multivariable analysis of patients' first samples revealed 12 biomarkers (CCL2, IL-15, soluble ST2 [sST2], NGAL, sTNFRSF1A, ferritin, IL-6, S100A9, MMP-9, IL-2, sVEGFR1, IL-10) that when increased were independently associated with mortality. Multivariate analyses of longitudinal biomarker trajectories identified 8 of the aforementioned biomarkers (IL-15, IL-2, NGAL, CCL2, MMP-9, sTNFRSF1A, sST2, IL-10) and 2 additional biomarkers (lactoferrin, CXCL9) that were substantially associated with mortality when increased, while IL-1α was associated with mortality when decreased. Among these, sST2, sTNFRSF1A, IL-10, and IL-15 were consistently higher throughout the hospitalization in patients who died versus those who recovered, suggesting that these biomarkers may provide an early warning of eventual disease outcome.
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http://dx.doi.org/10.1172/jci.insight.144455DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7821609PMC
January 2021

Inappropriate empirical antibiotic therapy for bloodstream infections based on discordant in-vitro susceptibilities: a retrospective cohort analysis of prevalence, predictors, and mortality risk in US hospitals.

Lancet Infect Dis 2021 02 8;21(2):241-251. Epub 2020 Sep 8.

Epidemiology Unit, Division of Intramural Research, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, MD, USA; United States Public Health Service, Commissioned Corps, Rockville, MD, USA.

Background: The prevalence and effects of inappropriate empirical antibiotic therapy for bloodstream infections are unclear. We aimed to establish the population-level burden, predictors, and mortality risk of in-vitro susceptibility-discordant empirical antibiotic therapy among patients with bloodstream infections.

Methods: Our retrospective cohort analysis of electronic health record data from 131 hospitals in the USA included patients with suspected-and subsequently confirmed-bloodstream infections who were treated empirically with systemic antibiotics between Jan 1, 2005, and Dec 31, 2014. We included all patients with monomicrobial bacteraemia caused by common bloodstream pathogens who received at least one systemic antibiotic either on the day blood cultures were drawn or the day after, and for whom susceptibility data were available. We calculated the prevalence of discordant empirical antibiotic therapy-which was defined as receiving antibiotics on the day blood culture samples were drawn to which the cultured isolate was not susceptible in vitro-overall and by hospital type by using regression tree analysis. We used generalised estimating equations to identify predictors of receiving discordant empirical antibiotic therapy, and used logistic regression to calculate adjusted odds ratios for the relationship between in-hospital mortality and discordant empirical antibiotic therapy.

Findings: 21 608 patients with bloodstream infections received empirical antibiotic therapy on the day of first blood culture collection. Of these patients, 4165 (19%) received discordant empirical antibiotic therapy. Discordant empirical antibiotic therapy was independently associated with increased risk of mortality (adjusted odds ratio 1·46 [95% CI, 1·28-1·66]; p<0·0001), a relationship that was unaffected by the presence or absence of resistance or sepsis or septic shock. Infection with antibiotic-resistant species strongly predicted receiving discordant empirical therapy (adjusted odds ratio 9·09 [95% CI 7·68-10·76]; p<0·0001). Most incidences of discordant empirical antibiotic therapy and associated deaths occurred among patients with bloodstream infections caused by Staphylococcus aureus or Enterobacterales.

Interpretation: Approximately one in five patients with bloodstream infections in US hospitals received discordant empirical antibiotic therapy, receipt of which was closely associated with infection with antibiotic-resistant pathogens. Receiving discordant empirical antibiotic therapy was associated with increased odds of mortality overall, even in patients without sepsis. Early identification of bloodstream pathogens and resistance will probably improve population-level outcomes.

Funding: US National Institutes of Health, US Centers for Disease Control and Prevention, and US Agency for Healthcare Research and Quality.
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http://dx.doi.org/10.1016/S1473-3099(20)30477-1DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7855478PMC
February 2021

Mycobacterial Testing Trends, United States, 2009-2015.

Emerg Infect Dis 2020 09;26(9):2243-2246

We studied 31 US healthcare facilities to characterize trends in mycobacterial testing. During 2009-2015, testing for acid-fast bacilli increased 3.2% annually, and prevalence of pathogenic nontuberculous mycobacteria increased 4.5% annually. These increases were highest for subpopulations at high risk of infection, including older women, Asians, and patients with concurrent conditions.
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http://dx.doi.org/10.3201/eid2609.200749DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7454078PMC
September 2020

Invasive Candidiasis Species Distribution and Trends, United States, 2009-2017.

J Infect Dis 2021 Apr;223(7):1295-1302

Epidemiology Unit, Laboratory of Clinical Immunology and Microbiology, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, Maryland, USA.

Background: Invasive candidiasis (IC) is a growing concern among US healthcare facilities. A large-scale study evaluating incidence and trends of IC in the United States by species and body site is needed to understand the distribution of infection.

Methods: An electronic medical record database was used to calculate incidence and trends of IC in the United States by species and infection site from 2009 through 2017. Hospital incidence was calculated using total unique inpatient hospitalizations in hospitals reporting at least 1 Candida case as the denominator. IC incidence trends were assessed using generalized estimating equations with exchangeable correlation structure to fit Poisson regression models, controlling for changes in hospital characteristics and case mix over time.

Results: Candida albicans remains the leading cause of IC in the United States, followed by Candida glabrata. The overall incidence of IC was 90/100 000 patients, which did not change significantly over time. There were no changes in incidence among C. albicans, C. glabrata, C. parapsilosis, or C. tropicalis; the incidence of other Candida spp. as a whole increased 7.2% annually. While there was no change in candidemia 2009-2017, abdominal and nonabdominal sterile site IC increased significantly.

Conclusions: Nonbloodstream IC is increasing in the United States. Understanding the epidemiology of IC should facilitate improved management of infected patients.
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http://dx.doi.org/10.1093/infdis/jiaa502DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8030726PMC
April 2021

External Validation of Difficult-to-Treat Resistance Prevalence and Mortality Risk in Gram-Negative Bloodstream Infection Using Electronic Health Record Data From 140 US Hospitals.

Open Forum Infect Dis 2019 Apr 28;6(4):ofz110. Epub 2019 Feb 28.

Epidemiology Unit, Division of Intramural Research, National Institutes of Allergy and Infectious Disease, National Institutes of Health, Bethesda, Maryland.

Difficult-to-treat resistance (DTR; ie, co-resistance to all first-line antibiotics) in gram-negative bloodstream infection (GNBSI) is associated with decreased survival in administrative data models. We externally validated DTR prevalence and associated mortality risk in GNBSI using detailed clinical data from electronic health records to adjust for baseline differences in acute illness severity.
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http://dx.doi.org/10.1093/ofid/ofz110DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6441782PMC
April 2019

Dwindling Utilization of Central Venous Catheter Tip Cultures: An Analysis of Sampling Trends and Clinical Utility at 128 US Hospitals, 2009-2014.

Clin Infect Dis 2019 10;69(10):1797-1800

Critical Care Medicine Department, National Institutes of Health Clinical Center, Maryland.

At 128 US hospitals, from 2009-2014, a 17% decline occurred annually in central venous catheter tips sent for culture: a 6-fold decrease from blood culture sampling trends. The positive predictive value was low (23%). Tip culture use often does not conform to recommendations and offers limited independent treatment opportunities.
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http://dx.doi.org/10.1093/cid/ciz218DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6821238PMC
October 2019

Hospital-based antibiotic use in patients with complex.

ERJ Open Res 2018 Oct 2;4(4). Epub 2018 Nov 2.

Epidemiology Unit, Division of Intramural Research, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, MD, USA.

Treatment guidelines exist for pulmonary complex (MAC) infection, although studies suggest poor concordance in clinician practice. Using a national database including hospital encounters of laboratory-confirmed MAC patients, we sought to characterise US treatment practices. We assessed patients in the Premier Healthcare Database from 2009 to 2013 with two or more MAC-positive cultures or one MAC-positive culture and the International Classification of Diseases (9th revision) code for pulmonary nontuberculous mycobacteria (PNTM). Treatment was characterised by patient-, provider- and facility-level factors; significant differences were assessed (p<0.05). Multilevel Poisson regression estimated adjusted relative risks (aRR) of receiving guidelines-based or macrolide resistance-promoting regimens. Of 1326 MAC patients, 645 (49%) received treatment: 10% received guidelines-based treatment and 18% resistance-associated therapy. Patients were more likely to receive guidelines-based therapy if they had multiple hospital encounters (aRR 1.5), codes for PNTM (aRR 5.7) or tuberculosis (aRR 4.5) or radiological procedures (aRR 10.9); multiple hospital encounters (aRR 0.8) or a tuberculosis code (aRR 0.1) were less likely to be associated with receiving resistance-promoting regimens. In hospital-based MAC patients, half received antibiotics active against MAC, a low proportion received therapy based on MAC guidelines and many received antibiotics that promote macrolide resistance. Improved implementation of guidelines-based treatment is needed to decrease use of regimens associated with macrolide resistance.
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http://dx.doi.org/10.1183/23120541.00109-2018DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6213287PMC
October 2018

Associations between ideational variables and bed net use in Madagascar, Mali, and Nigeria.

BMC Public Health 2018 04 11;18(1):484. Epub 2018 Apr 11.

Johns Hopkins Center for Communication Programs, 111 Market Place, Suite 310, Baltimore, MD, 21202, USA.

Background: The use of insecticide-treated bed nets (ITNs) is crucial to the prevention, control, and elimination of malaria. Using household surveys conducted in 2014-2015 by the Health Communication Capacity Collaborative project in Madagascar, Mali, and Nigeria, we compared a model of psychosocial influence, called Ideation, to examine how malaria-related variables influence individual and household bed net use in each of these countries. Evaluations of non-malaria programs have confirmed the value of the ideational approach, but it is infrequently used to guide malaria interventions. The study objective was to examine how well this model could identify potentially effective malaria prevention approaches in different contexts.

Methods: Sampling and survey designs were similar across countries. A multi-stage random sampling process selected female caregivers with at least one child under 5 years of age for interviews. Additional data were collected from household heads about bed net use and other characteristics of household members. The caregiver survey measured psychosocial variables that were subjected to bivariate and multivariate analysis to identify significant ideational variables related to bed net use.

Results: In all three countries, children and adolescents over five were less likely to sleep under a net compared to children under five (OR = 0.441 in Madagascar, 0.332 in Mali, 0.502 in Nigeria). Adults were less likely to sleep under a net compared to children under five in Mali (OR = 0.374) and Nigeria (OR = 0.448), but not Madagascar. In all countries, the odds of bed net use were lower in larger compared to smaller households (OR = 0.452 in Madagascar and OR = 0.529 in Nigeria for households with 5 or 6 members compared to those with less than 5; and OR = 0.831 in Mali for larger compared to smaller households). Of 14 common ideational variables examined in this study, six were significant predictors in Madagascar (all positive), three in Mali (all positive), and two in Nigeria (both negative).

Conclusion: This research suggests that the systematic use of this model to identify relevant ideational variables in a particular setting can guide the development of communication strategies and messaging, thereby improving the effectiveness of malaria prevention and control.
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http://dx.doi.org/10.1186/s12889-018-5372-2DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5896159PMC
April 2018

The use of mediation analysis to assess the effects of a behaviour change communication strategy on bed net ideation and household universal coverage in Tanzania.

Malar J 2015 Jan 21;14:15. Epub 2015 Jan 21.

Johns Hopkins Center for Communication Programs, Johns Hopkins Bloomberg School of Public Health, 111 Market Place Suite 310, Baltimore 21202, MD, USA.

Background: SBCC campaigns are designed to act on cognitive, social and emotional factors at the individual or community level. The combination of these factors, referred to as 'ideation', play a role in determining behaviour by reinforcing and confirming decisions about a particular health topic. This study introduces ideation theory and mediation analysis as a way to evaluate the impact of a malaria SBCC campaign in Tanzania, to determine whether exposure to a communication programme influenced universal coverage through mediating ideational variables.

Methods: A household survey in three districts where community change agents (CCAs) were active was conducted to collect information on ITN use, number of ITNs in the household, and perceptions about ITN use and ownership. Variables relating to attitudes and beliefs were combined to make 'net ideation'. Using an ideational framework, a mediation analysis was conducted to see the impact exposure to a CCA only, mass media and community (M & C) messaging only, or exposure to both, had on household universal coverage, through the mediating variable net ideation.

Results: All three levels of exposure (CCA, M & C messaging, or exposure to both) were significantly associated with increased net ideation (CCA: 0.283, 95% CI: 0.136-0.429, p-value: <0.001; M & C: 0.128, 95% CI: 0.032-0.334, p-value: 0.018; both: 0.376, 95% CI: 0.170-0.580, p-value: <0.001). Net ideation also significantly increased the odds of having universal coverage (CCAOR: 1.265, 95% CI: 1.118-1.433, p-value: <0.001; M & COR: 1.264, 95% CI: 1.117-1.432, p-value: <0.001, bothOR: 1.260, 95% CI: 1.114-1.428, p-value: <0.001). There were no significant direct effects between any exposure and universal coverage when controlling for net ideation.

Conclusions: The results of this study indicate that mediation analysis is an applicable new tool to assess SBCC campaigns. Ideation as a mediator of the effects of communication exposure on household universal coverage has implications for designing SBCC to support both mass and continuous distribution efforts, since both heavily rely on consumer participation to obtain and maintain ITNs. Such systems can be strengthened by SBCC programming, generating demand through improving social norms about net ownership and use, perceived benefits of nets, and other behavioural constructs.
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http://dx.doi.org/10.1186/s12936-014-0531-0DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4308934PMC
January 2015

Epidemiology and antimicrobial resistance of international travel-associated Campylobacter infections in the United States, 2005-2011.

Am J Public Health 2014 Jul 15;104(7):e108-14. Epub 2014 May 15.

Emily E. Ricotta, Amanda Palmer, Patricia Ryan, and David Blythe are with the Maryland Department of Health and Mental Hygiene, Baltimore. Katie Wymore is with Public Health Foundation Enterprises, Oakland, CA. Paula Clogher is with the Yale School of Public Health, New Haven, CT. Nadine Oosmanally is with the Georgia Department of Public Health, Atlanta. Trisha Robinson is with the Minnesota Department of Health, St. Paul. Sarah Lathrop is with the University of New Mexico, Alburquerque. Jillian Karr is with the New York State Department of Health, Rochester. Julie Hatch is with the Oregon Health Authority, Public Health Division, Portland. John Dunn is with the Tennessee Department of Health, Nashville.

Objectives: The objective of this study was to determine the role international travel plays in US Campylobacter epidemiology and antimicrobial resistance.

Methods: In this study, epidemiological and antimicrobial resistance data, encompassing the years 2005 to 2011, from 10 sites participating in the Foodborne Diseases Active Surveillance Network were linked. The 10 sites are represented by 7 states that conducted surveillance on a statewide level, and 3 states which conducted county-level surveillance. Cases of Campylobacter among persons with history of international travel in the week prior to illness were compared with cases among individuals with no international travel.

Results: Approximately 18% of Campylobacter infections were estimated to be associated with international travel, and 60% of international travel-associated infections had a quinolone-resistant Campylobacter isolate.

Conclusions: We confirm that international travel plays a significant role in campylobacteriosis diagnosed in the United States. Recognizing this is important to both medical management decisions and understanding burden and attribution estimates of US campylobacteriosis and antibiotic-resistant campylobacteriosis.
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http://dx.doi.org/10.2105/AJPH.2013.301867DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4056211PMC
July 2014

Evaluating local vegetation cover as a risk factor for malaria transmission: a new analytical approach using ImageJ.

Malar J 2014 Mar 13;13:94. Epub 2014 Mar 13.

W, Harry Feinstone Department of Molecular Microbiology and Immunology, Johns Hopkins Bloomberg School of Public Health, Baltimore, Maryland, USA.

Background: In places where malaria transmission is unstable or is transmitted under hypoendemic conditions, there are periods where limited foci of cases still occur and people become infected. These residual "hot spots" are likely reservoirs of the parasite population and so are fundamental to the seasonal spread and decline of malaria. It is, therefore, important to understand the ecological conditions that permit vector mosquitoes to survive and forage in these specific areas. Features such as local waterways and vegetation, as well as local ecology, particularly nocturnal temperature, humidity, and vegetative sustainability, are important for modeling local mosquito behavior. Vegetation around a homestead likely provides refuge for outdoor resting of these insects and may be a risk factor for malaria transmission. Analysis of this vegetation can be done using satellite information and mapping programs, such as Google Earth, but manual quantification is difficult and can be tedious and subjective. A more objective method is required.

Methods: Vegetation cover in the environment is reasonably static, particularly in and around homesteads. In order to evaluate and enumerate such information, ImageJ, an image processing software, was used to analyse Google Earth satellite imagery. The number of plants, total amount of vegetation around a homestead and its percentage of the total area were calculated and related to homesteads where cases of malaria were recorded.

Results: Preliminary results were obtained from a series of field trials carried out in South East Zambia in the Choma and Namwala districts from a base at the Macha District Hospital.

Conclusions: This technique is objective, clear and simple to manipulate and has potential application to determine the role that vegetation proximal to houses may play in affecting mosquito behaviour, foraging and subsequent malaria incidence.
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http://dx.doi.org/10.1186/1475-2875-13-94DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4007634PMC
March 2014

Rapid divergence of two classes of Haemophilus ducreyi.

J Bacteriol 2011 Jun 22;193(12):2941-7. Epub 2011 Apr 22.

Department of Biology, Allegheny College, Meadville, PA 16335, USA.

Haemophilus ducreyi, the etiologic agent of chancroid, expresses variants of several key virulence factors. While previous reports suggested that H. ducreyi strains formed two clonal populations, the differences between, and diversity within, these populations were unclear. To assess their variability, we examined sequence diversity at 11 H. ducreyi loci, including virulence and housekeeping genes, augmenting published data sets with PCR-amplified genes to acquire data for at least 10 strains at each locus. While sequences from all 11 loci place strains into two distinct groups, there was very little variation within each group. The difference between alleles of the two groups was variable and large at 3 loci encoding surface-exposed proteins (0.4 < K(S) < 1.3, where K(S) is divergence at synonymous sites) but consistently small at genes encoding cytoplasmic or periplasmic proteins (K(S) < 0.09). The data suggest that the two classes have recently diverged, that recombination has introduced variant alleles into at least 3 distinct loci, and that these alleles have been confined to one of the two classes. In addition, recombination is evident among alleles within, but not between, classes. Rather than clones of the same species, these properties indicate that the two classes may form distinct species.
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http://dx.doi.org/10.1128/JB.01400-10DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3133207PMC
June 2011