BACKGROUND: Prolonged diarrhoea is common amongst returning travellers and is often caused by intestinal protozoa. However, the epidemiology of travel-associated illness caused by protozoal pathogens is not well described. METHODS: We analysed records of returning international travellers with illness caused by Giardia duodenalis, Cryptosporidium spp., Cyclospora cayetanensis or Cystoisospora belli, reported to the GeoSentinel Network during January 2007-December 2019. We excluded records of travellers migrating, with an unascertainable exposure country, or from GeoSentinel sites that were not located in high-income countries. RESULTS: There were 2517 cases, 82.3% giardiasis (n = 2072), 11.4% cryptosporidiosis (n = 287), 6.0% cyclosporiasis (n = 150) and 0.3% cystoisosporiasis (n = 8). Overall, most travellers were tourists (64.4%) on long trips (median durations: 18-30 days). Cryptosporidiosis more frequently affected people < 18 years (13.9%) and cyclosporiasis affected people ≥ 40 years (59.4%). Giardiasis was most frequently acquired in South Central Asia (45.8%) and sub-Saharan Africa (22.6%), cryptosporidiosis in sub-Saharan Africa (24.7%) and South-Central Asia (19.5%), cyclosporiasis in South East Asia (31.3%) and Central America (27.3%), and cystoisosporiasis in sub-Saharan Africa (62.5%). Cyclosporiasis cases were reported from countries of uncertain endemicity (e.g. Cambodia) or in countries with no previous evidence of this parasite (e.g. French Guiana). The time from symptom onset to presentation at a GeoSentinel site was the longest amongst travellers with giardiasis (median: 30 days). Over 14% of travellers with cryptosporidiosis were hospitalized. CONCLUSIONS: This analysis provides new insights into the epidemiology and clinical significance of four intestinal protozoa that can cause morbidity in international travellers. These data might help optimize pretravel advice and post-travel management of patients with travel-associated prolonged gastrointestinal illnesses. This analysis reinforces the importance of international travel-related surveillance to identify sentinel cases and areas where protozoal infections might be undetected or underreported.

The Centers for Disease Control and Prevention (CDC) and the broader public health system safeguard the health security of people in the United States through science and innovative practices.1,2 Obtaining high-quality, timely data enables public health partners to learn about emerging pathogens, track trends, and identify adversely affected populations. However, the COVID-19 pandemic and other public health emergencies have revealed a fragmented landscape of data and data infrastructure at all levels that limits data access and use, creates security risks, and impedes science, innovation, and collaboration.3,4 Sustainable progress is needed for effective collection, management, and sharing of diverse volumes of data across the public health system to inform timely surveillance, epidemiologic, and laboratory activities. Improving data readiness to link data, decisions, and action may require public health agencies and their constituents to adopt new practices and innovations, build a culture around data, implement common policies and standards, develop decision-support tools, and expand the capacity of the data science workforce.

BACKGROUND: Assessing the global risk of rabies exposure is a complicated task requiring individual risk assessments, knowledge of rabies epidemiology, surveillance capacity, and accessibility of rabies biologics on a national and regional scale. In many parts of the world, availability of this information is limited and when available is often dispersed across multiple sources. This hinders the process of making evidence-based health and policy recommendations to prevent the introduction and spread of rabies. METHODS: CDC conducted a country-by-country qualitative assessment of risk and protective factors for rabies to develop an open-access database of core metrics consisting of the presence of Lyssaviruses (specifically canine or wildlife rabies virus variants or other bat Lyssaviruses), access to rabies immunoglobulins and vaccines, rabies surveillance capacity, and canine rabies control capacity. Using these metrics, we developed separate risk scoring systems to inform rabies prevention guidance for travelers and regulations for the importation of dogs. Both scoring systems assigned higher risk to countries with enzootic rabies (particularly canine rabies), and the risk scoring system for travelers also considered protective factors such as the accessibility of rabies biologics for postexposure prophylaxis. Cumulative scores were calculated across the assessed metrics to assign a risk value of low, moderate, or high. RESULTS: A total of 240 countries, territories, and dependencies were assessed, for travelers, 116 were identified as moderate to high risk and 124 were low or no risk; for canine rabies virus variant importation, 111 were identified as high-risk and 129 were low or no risk. CONCLUSIONS: We developed a comprehensive and easily accessible source of information for assessing the rabies risk for individual countries that included a database of rabies risk and protective factors based on enzootic status and availability of biologics, provided a resource that categorizes risk by country, and provided guidance based on these risk categories for travelers and importers of dogs into the United States.

BACKGROUND: Australia was verified to have eliminated rubella in 2017. This success is attributed to Australia's longstanding national immunisation programme and two enhanced measles immunisation activities using measles, mumps, and rubella (MMR) vaccines - Measles Control Campaign (MCC) and Young Adult MMR Campaign (YAC). The impact of these activities on rubella incidence and its elimination in Australia is described. METHODS: Aggregate national serological survey data were assigned to birth cohorts and mean, median and age-group estimates calculated and analysed against MMR immunisation coverage estimates (1998-2018) and rubella notifications (1993-2018). Three-year cumulative incidences were calculated by birth cohort. RESULTS: Serological surveys revealed high stable levels of rubella immunity among females but estimates for three male cohorts were lower. Since 2007, MMR immunisation coverage among children aged 24-27 months has remained above 90% for both doses. The three-year cumulative incidence of rubella declined across all birth cohorts following the MCC and the YAC. DISCUSSION: Using MMR vaccines to address measles immunity gaps had a symbiotic benefit in controlling rubella in Australia. Both the MCC and YAC shifted rubella epidemiology, accelerating the interruption of endemic transmission. Countries should consider combined measles and rubella vaccines for all catch-up activities.

Laboratory scientists of the US Centers for Disease Control and Prevention (CDC) and other public health laboratories play a fundamental and increasingly complex role in implementing public health programs while ensuring laboratory safety and quality. In 2014, a series of laboratory safety incidents highlighted the need for improvement in federal and other government laboratories. One component of the CDC's response to these incidents was a new career-entry fellowship program, the Laboratory Leadership Service (LLS). Offering laboratory safety and quality training and leadership development for laboratory scientists, LLS is intended to create a pipeline of future laboratory leaders who prioritize quality and safety as a core part of their laboratory science and practice throughout their careers. LLS incorporates evidence-based practices such as the service-learning model, a competency-based curriculum, ongoing stakeholder engagement, and program evaluation to maximize the program's success. This article describes how the CDC created LLS as a workforce development measure to respond to an urgent public health need-to improve laboratory safety and quality-and presents key factors for success in quickly establishing the program.

CONTEXT: Antiretroviral therapy (ART) to treat and pre-exposure prophylaxis (PrEP) to prevent HIV infection are effective tools to help end the HIV epidemic. However, their use could affect HIV transfusion-transmission risk. OBJECTIVES: Three different ART/PrEP prevalence analyses in blood donors were conducted. METHODS: First, blood samples from HIV-positive and a comparison group of infection-nonreactive donors were tested under blind using liquid chromatography-tandem mass spectrometry for ART. Second, blood donor samples from infection-nonreactive, 18-45 year-old, male, first-time blood donors in six US locations were tested for emtricitabine and tenofovir. Third, in men who have sex with men (MSM) participating in the 2017 CDC National HIV Behavioral Surveillance (NHBS) from five US cities self-reported PrEP use proximate to donation was assessed. FINDINGS: In blind testing, no ART was detected in 300 infection-nonreactive donor samples, but in 299 HIV-confirmed infected donor samples, 46 (15.4%, 95% CI 11.5 - 20.0%) had evidence of ART. Of the 1,494 samples tested from first-time, male donors, 9 (0.6%, 95% CI 0.03 - 1.1%) had tenofovir and emtricitabine. In the NHBS MSM survey, 27 of 591 respondents (4.8%, 95% CI 3.2 - 6.9%) reported donating blood in 2016 or 2017 and PrEP use within the same time frame as blood donation. CONCLUSIONS: Persons who are HIV-positive and taking ART and persons taking PrEP to prevent HIV infection are donating blood. Both situations could lead to increased risk of HIV transfusion transmission if blood screening assays are unable to detect HIV in donations from infected donors.

Fellowship programs offer career development opportunities, provide experiential training, and can be used to recruit personnel to address specific challenges facing the public health workforce. Given the potential influence fellowships have on the future public health workforce, it is important to understand and articulate the results of such programs and to identify areas of improvement to meet current workforce needs. The purpose of this literature review was to identify common practices used to evaluate nonclinical fellowship programs. After a search of the internet and selected databases, we screened titles and abstracts using predetermined selection criteria. We then conducted a detailed review of selected papers to extract information about program characteristics (program description, sector, and program length) and evaluation characteristics (primary evaluation type, framework for evaluation, data collection methods, and respondent populations) from 33 papers. We found a limited number of published papers on the evaluation of nonclinical fellowship programs, and most focused on outcomes associated with fellows or alumni. The most useful papers for our purposes clearly described the evaluation framework that guided the evaluation.

BACKGROUND: Expert groups have recommended ongoing monitoring of the public health workforce to determine its ability to execute designated objectives. Resource- and time-intensive surveys have been a primary data source to monitor the workforce. We evaluated an administrative data source containing US Department of Health and Human Services (HHS) aggregate federal civil service workforce-related data to determine its potential as a workforce surveillance system for this component of the workforce. METHODS: We accessed FedScope, a publicly available online database containing federal administrative civilian HHS personnel data. Using established guidelines for evaluating surveillance systems and identified workforce characteristics, we evaluated FedScope attributes for workforce surveillance purposes. RESULTS: We determined FedScope to be a simple, highly accepted, flexible, stable, and timely system to support analyses of federal civil service workforce-related data. Data can be easily accessed, analyzed, and monitored for changes across years and draw conclusions about the workforce. FedScope data can be used to calculate demographics (eg, sex, race or ethnicity, age group, and education level), employment characteristics (ie, supervisory status, work schedule, and appointment type), retirement projections, and characterize the federal workforce into standard occupational categories. CONCLUSIONS: This study indicates that an administrative data source containing HHS personnel data can function as a workforce surveillance system valuable to researchers, public health leaders, and decision makers interested in the federal civil service public health workforce. Using administrative data for workforce development is a model that can be applicable to federal and nonfederal public health agencies and ultimately support improvements in public health.

CONTEXT: Public health has a responsibility to ensure the ability of its workforce to deliver essential services, including mastering the core public health competencies. PROGRAM: The Division of Scientific Education and Professional Development (DSEPD) of the Centers for Disease Control and Prevention has a mission to improve health outcomes through a competent, sustainable, and empowered public health workforce. The DSEPD programs offer fellowships and other training opportunities, develop and disseminate quality public health training, and advance public health workforce development science. EVALUATION: The DSEPD developed a unified division logic model to describe the combined activities and intended outcomes of all DSEPD programs and their intended contribution to a robust public health workforce and to support ongoing program planning and evaluation. The logic model has 4 streams of work that include (1) producing and disseminating quality learning products; (2) implementing and managing fellowship programs that support learning; (3) providing public health service through fellows; and (4) advancing workforce development science through collaboration with other public health leaders.The underlying program theory is that a robust workforce has sufficient workforce, organizational, and systems capacity to deliver public health essential services and, therefore, to protect the public's health. Three scientific theories support the program theory: the quality of learning; the accepted practice of competency-based programs and the service-learning model; and use of evidence-guided decision making in workforce development programs. DISCUSSION: A unified division logic model allows DSEPD to describe its combined approaches to workforce development as a coherent portfolio with well-defined goals and measureable outcomes. The logic model effectively communicates the relationship among division programs, their shared outcomes, and their combined contributions to developing and maintaining a robust public health workforce. A unified logic model can serve as effective frame of reference for division evaluation and as evidence in public health workforce development science.

Twenty-five years ago, the 10 essential public health services were defined and disseminated1 and public health was charged with ensuring that our workforce had mastery of the competencies to deliver these services.2,3 Although these essential services remain a useful framework for the practice of public health, the concept of an effective public health worker has evolved in the intervening decades. The necessary skills and aptitudes now extend beyond the traditional competencies (eg, epidemiology) to focus on strategic and systems thinking, communication, and translating science to policy, along with the public health practitioner's role as chief health strategist.4–8 A subcommittee of the Public Health Functions Project Steering Committee laid out an agenda in 1994 to realize the vision of “Healthy People in Healthy Communities” and recommended actions in 5 main areas (national leadership, state and local leadership, workforce composition, curriculum development, and distance learning).1 Progress in each of these 5 areas has been documented,9–11 with particularly substantial advances observed in the last 5 years.12–16 From a federal perspective, we believe that the recent, increasing rate of these advances can be attributed to a few main factors. Collaboration among federal and other partners working at the national level has provided the necessary leadership. Partners have built upon each other's work rather than working in isolation. Accreditation of health departments has provided a consistent approach for strengthening state and local health agencies. Researchers have taken action and are building evidence that informs practice at the federal, state, tribal, local, and territorial levels. Nonetheless, gaps remain. Using the areas for action as a framework and a federal perspective, we highlight recent accomplishments and important areas for future attention to continue the path toward the public health workforce of the 21st century—a public heath workforce 3.0.

BACKGROUND: Isoniazid-resistant, rifampicin-susceptible (INH-R) tuberculosis is the most common form of drug resistance, and is associated with failure, relapse, and acquired rifampicin resistance if treated with first-line anti-tuberculosis drugs. The aim of the study was to compare success, mortality, and acquired rifampicin resistance in patients with INH-R pulmonary tuberculosis given different durations of rifampicin, ethambutol, and pyrazinamide (REZ); a fluoroquinolone plus 6 months or more of REZ; and streptomycin plus a core regimen of REZ. METHODS: Studies with regimens and outcomes known for individual patients with INH-R tuberculosis were eligible, irrespective of the number of patients if randomised trials, or with at least 20 participants if a cohort study. Studies were identified from two relevant systematic reviews, an updated search of one of the systematic reviews (for papers published between April 1, 2015, and Feb 10, 2016), and personal communications. Individual patient data were obtained from authors of eligible studies. The individual patient data meta-analysis was performed with propensity score matched logistic regression to estimate adjusted odds ratios (aOR) and risk differences of treatment success (cure or treatment completion), death during treatment, and acquired rifampicin resistance. Outcomes were measured across different treatment regimens to assess the effects of: different durations of REZ (</=6 months vs >6 months); addition of a fluoroquinolone to REZ (fluoroquinolone plus 6 months or more of REZ vs 6 months or more of REZ); and addition of streptomycin to REZ (streptomycin plus 6 months of rifampicin and ethambutol and 1-3 months of pyrazinamide vs 6 months or more of REZ). The overall quality of the evidence was assessed using GRADE methodology. FINDINGS: Individual patient data were requested for 57 cohort studies and 17 randomised trials including 8089 patients with INH-R tuberculosis. We received 33 datasets with 6424 patients, of which 3923 patients in 23 studies received regimens related to the study objectives. Compared with a daily regimen of 6 months of (H)REZ (REZ with or without isoniazid), extending the duration to 8-9 months had similar outcomes; as such, 6 months or more of (H)REZ was used for subsequent comparisons. Addition of a fluoroquinolone to 6 months or more of (H)REZ was associated with significantly greater treatment success (aOR 2.8, 95% CI 1.1-7.3), but no significant effect on mortality (aOR 0.7, 0.4-1.1) or acquired rifampicin resistance (aOR 0.1, 0.0-1.2). Compared with 6 months or more of (H)REZ, the standardised retreatment regimen (2 months of streptomycin, 3 months of pyrazinamide, and 8 months of isoniazid, rifampicin, and ethambutol) was associated with significantly worse treatment success (aOR 0.4, 0.2-0.7). The quality of the evidence was very low for all outcomes and treatment regimens assessed, owing to the observational nature of most of the data, the diverse settings, and the imprecision of estimates. INTERPRETATION: In patients with INH-R tuberculosis, compared with treatment with at least 6 months of daily REZ, addition of a fluoroquinolone was associated with better treatment success, whereas addition of streptomycin was associated with less treatment success; however, the quality of the evidence was very low. These results support the conduct of randomised trials to identify the optimum regimen for this important and common form of drug-resistant tuberculosis. FUNDING: World Health Organization and Canadian Institutes of Health Research.

Measuring tuberculosis transmission is exceedingly difficult, given the remarkable variability in the timing of clinical disease after Mycobacterium tuberculosis infection; incident disease can result from either a recent (ie, weeks to months) or a remote (ie, several years to decades) infection event. Although we cannot identify with certainty the timing and location of tuberculosis transmission for individuals, approaches for estimating the individual probability of recent transmission and for estimating the fraction of tuberculosis cases due to recent transmission in populations have been developed. Data used to estimate the probable burden of recent transmission include tuberculosis case notifications in young children and trends in tuberculin skin test and interferon gamma-release assays. More recently, M. tuberculosis whole-genome sequencing has been used to estimate population levels of recent transmission, identify the distribution of specific strains within communities, and decipher chains of transmission among culture-positive tuberculosis cases. The factors that drive the transmission of tuberculosis in communities depend on the burden of prevalent tuberculosis; the ways in which individuals live, work, and interact (eg, congregate settings); and the capacity of healthcare and public health systems to identify and effectively treat individuals with infectious forms of tuberculosis. Here we provide an overview of these factors, describe tools for measurement of ongoing transmission, and highlight knowledge gaps that must be addressed.

CONTEXT: A highly skilled public health workforce is needed for responding to health threats, and that workforce must be able to communicate its scientific findings effectively. OBJECTIVE: We evaluated the scientific communication effectiveness of the Centers for Disease Control and Prevention's (CDC's) field-based Epidemic Intelligence Service officers (EISOs). DESIGN: A descriptive analysis of all scientific information products produced and submitted for institutional clearance by CDC's field-based EISOs during 2009-2014. MAIN OUTCOME MEASURE(S): The number of abstracts, journal manuscripts, Morbidity and Mortality Weekly Reports (MMWRs), and other information products approved by CDC during 2009-2014; the number of those products published; and of those published, the number cited in the scientific literature. RESULTS: During 2009-2014, a total of 152 field-based EISOs produced 835 scientific information products, including 437 abstracts, 261 manuscripts, and 103 MMWRs. The majority of scientific information products submitted for clearance were abstracts (52.3%), and infectious diseases (75.3%) constituted the majority of topics. Among the 103 MMWRs and 261 manuscripts cleared, 88 (85%) and 199 (76%) were published, respectively, with the majority also infectious disease-related. The 199 published manuscripts were cited in the scientific literature 2415 times, and the 88 published MMWRs were cited 1249 times. Field-based EISOs published their work in 74 different peer-reviewed medical and public health journals, with 54% published in journals with impact factors of 1 to 5. CONCLUSIONS: Field-based EISOs' publications are a measurable marker that reflects proficiency in epidemiology, written communication, and professionalism, and those publications are a direct reflection of EISOs' contribution to local and state health departments. Our study establishes a baseline for future evaluations of publication outcome of scientific information products by EISOs. Information released by EISOs provides health professionals with the scientific knowledge necessary for improving their practice and helps CDC achieve a broader societal, environmental, cultural, and economic impact.

Molecular data are now widely used in epidemiological studies to investigate the transmission, distribution, biology, and diversity of pathogens. Our objective was to establish recommendations to support good scientific reporting of molecular epidemiological studies to encourage authors to consider specific threats to valid inference. The statement Strengthening the Reporting of Molecular Epidemiology for Infectious Diseases (STROME-ID) builds upon the Strengthening the Reporting of Observational Studies in Epidemiology (STROBE) initiative. The STROME-ID statement was developed by a working group of epidemiologists, statisticians, bioinformaticians, virologists, and microbiologists with expertise in control of infection and communicable diseases. The statement focuses on issues relating to the reporting of epidemiological studies of infectious diseases using molecular data that were not addressed by STROBE. STROME-ID addresses terminology, measures of genetic diversity within pathogen populations, laboratory methods, sample collection, use of molecular markers, molecular clocks, timeframe, multiple-strain infections, non-independence of infectious-disease data, missing data, ascertainment bias, consistency between molecular and epidemiological data, and ethical considerations with respect to infectious-disease research. In total, 20 items were added to the 22 item STROBE checklist. When used, the STROME-ID recommendations should advance the quality and transparency of scientific reporting, with clear benefits for evidence reviews and health-policy decision making.

CONTEXT: Studies characterizing the public health workforce are needed for providing the evidence on which to base planning and policy decision making both for workforce staffing and for addressing uncertainties regarding organizing, financing, and delivering effective public health strategies. The Centers for Disease Control and Prevention (CDC) is leading the enumeration of the US public health workforce with an initial focus on CDC as the leading federal public health agency. OBJECTIVE: To characterize CDC's workforce, assess retirement eligibility and potential staff losses, and contribute these data as the federal component of national enumeration efforts. METHODS: Two sources containing data related to CDC employees were analyzed. CDC's workforce was characterized by using data elements recommended for public health workforce enumeration and categorized the occupations of CDC staff into 15 standard occupational classifications by using position titles. Retirement eligibility and potential staffing losses were analyzed by using 1-, 3-, and 5-year increments and compared these data across occupational classifications to determine the future impact of potential loss of workforce. RESULTS: As of the first quarter of calendar year 2012, a total 11 223 persons were working at CDC; 10 316 were civil servants, and 907 were Commissioned Corps officers. Women accounted for 61%. Public health managers, laboratory workers, and administrative-clerical staff comprised the top 3 most common occupational classifications among CDC staff. Sixteen percent of the workforce was eligible to retire by December 2012, and more than 30% will be eligible to retire by December 2017. CONCLUSIONS: This study represents the first characterization of CDC's workforce and provides an evidence base upon which to develop policies for ensuring an ongoing ability to fulfill the CDC mission of maintaining and strengthening the public's health. Establishing a system for continually monitoring the public health workforce will support future efforts in understanding workforce shortages, capacity, and effectiveness; projecting trends; and initiating policies.

OBJECTIVE: The objective of this study was to evaluate the association between the use of monotherapy topiramate in pregnancy and cleft lip with or without cleft palate (CL/P) in the offspring. STUDY DESIGN: Data from the Slone Epidemiology Center Birth Defects Study (BDS) from 1997 to 2009 and the National Birth Defects Prevention Study (NBDPS) from 1997 to 2007 were analyzed. Conditional logistic regression was used to compare the first-trimester use of topiramate monotherapy to no antiepileptic drug use during the periconceptional period between the mothers of infants with CL/P and the mothers of controls for each study separately and in pooled data. RESULTS: The BDS contained 785 CL/P cases and 6986 controls; the NBDPS contained 2283 CL/P cases and 8494 controls. The odds ratios (exact 95% confidence intervals) for the association between topiramate use and CL/P were 10.1 (1.1-129.2) in the BDS, 3.6 (0.7-20.0) in the NBDPS, and 5.4 (1.5-20.1) in the pooled data. CONCLUSION: First-trimester use of topiramate may be associated with CL/P.

Murine leukemia viruses (MLVs), including xenotropic-MLV-related virus (XMRV), have been controversially linked to chronic fatigue syndrome (CFS). To explore this issue in greater depth, we compiled coded replicate samples of blood from 15 subjects previously reported to be XMRV/MLV-positive (14 with CFS) and from 15 healthy donors previously determined to be negative for the viruses. These samples were distributed in a blinded fashion to nine laboratories, which performed assays designed to detect XMRV/MLV nucleic acid, virus replication, and antibody. Only two laboratories reported evidence of XMRV/MLVs; however, replicate sample results showed disagreement, and reactivity was similar among CFS subjects and negative controls. These results indicate that current assays do not reproducibly detect XMRV/MLV in blood samples and that blood donor screening is not warranted.

Recently, there have been studies that indicate that Xenotropic Murine Leukemia Virus (MLV)-related Virus (XMRV), a newly described human gammaretrovirus, and other related viruses, may be associated with both prostate cancer and myalgic encephalomyelitis (ME) / chronic fatigue syndrome (CFS)1–4. It has also been suggested that these viruses have the potential to be transmitted by blood transfusion5. However, a number of studies have failed to support these associations, or indeed detect significant evidence of XMRV in the human population6–9. Currently, there is insufficient information to determine whether or not XMRV and related viruses are a threat to blood safety. Accordingly, the Department of Health and Human Services (HHS) has established a Scientific Research Working Group (SRWG) to explore the following questions: What is the prevalence of XMRV in the donor population? Is XMRV transmissible by blood transfusion? And if XMRV is transmissible by transfusion, are there any pathologic consequences for the infected recipient? As a starting point, the SRWG has focused on standardizing the various tests used to detect XMRV in blood samples and has facilitated the sharing of clinical samples between laboratories. This commentary discusses background information relating to blood safety and XMRV and related viruses and outlines the specific actions that the SRWG has taken and plans to take.

BACKGROUND: It is unclear whether human immunodeficiency virus (HIV) increases the risk of tuberculosis (TB) mainly through reactivation or following recent Mycobacterium tuberculosis (re)infection. Within a DNA fingerprint-defined cluster of TB cases, reactivation cases are assumed to be the source of infection for subsequent secondary cases. As HIV-positive TB cases are less likely to be source cases, equal or higher clustering in HIV-positives would suggest that HIV mainly increases the risk of TB following recent infection. METHODS: A systematic review was conducted to identify all studies on TB clustering and HIV infection in HIV-endemic populations. Available individual patient data from eligible studies were pooled to analyse the association between clustering and HIV. RESULTS: Of seven eligible studies, six contributed individual patient data on 2116 patients. Clustering was as, or more, likely in the HIV-positive population, both overall (summary OR 1.26, 95%CI 1.0-1.5), and within age groups (OR 1.50, 95%CI 0.9-2.3; OR 1.00, 95%CI 0.8-1.3 and OR 2.57, 95%CI 1.4-5.7) for ages 15-25, 26-50 and >50 years, respectively. CONCLUSIONS: Our results suggest that HIV infection mainly increases the risk of TB following recent M. tuberculosis transmission, and that TB control measures in HIV-endemic settings should therefore focus on controlling M. tuberculosis transmission rather than treating individuals with latent M. tuberculosis infection. 2011 The Union.

OBJECTIVES: To estimate HIV prevalence and characterize risk factors among young adults in Asembo, rural western Kenya. DESIGN: Community-based cross-sectional survey. METHODS: From a demographic surveillance system, we selected a random sample of residents aged 13-34 years, who were contacted at home and invited to a nearby mobile study site. Consent procedures for non-emancipated minors required assent and parental consent. From October 2003 - April 2004, consenting participants were interviewed on risk behavior and tested for HIV and HSV-2. HIV voluntary counseling and testing was offered. RESULTS: Of 2606 eligible residents, 1822 (70%) enrolled. Primary reasons for refusal included not wanting blood taken, not wanting to learn HIV status, and partner/parental objection. Females comprised 53% of 1762 participants providing blood. Adjusted HIV prevalence was 15.4% overall: 20.5% among females and 10.2% among males. HIV prevalence was highest in women aged 25-29 years (36.5%) and men aged 30-34 years (41.1%). HSV-2 prevalence was 40.0% overall: 53% among females, 25.8% among males. In multivariate models stratified by gender and marital status, HIV infection was strongly associated with age, higher number of sex partners, widowhood, and HSV-2 seropositivity. CONCLUSIONS: Asembo has extremely high HIV and HSV-2 prevalence, and probable high incidence, among young adults. Further research on circumstances around HIV acquisition in young women and novel prevention strategies (vaccines, microbicides, pre-exposure prophylaxis, HSV-2 prevention, etc.) are urgently needed.