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Background Emerging evidence suggests that black and Hispanic communities in the United States are disproportionately affected by coronavirus disease 2019 (COVID-19). A complex interplay of socioeconomic and healthcare disparities likely contribute to disproportionate COVID-19 risk. Methods We conducted a geospatial analysis to determine whether individual- and neighborhood-level attributes predict local odds of testing positive for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). We analyzed 29 138 SARS-CoV-2 tests within the 6-county catchment area for Duke University Health System from March to June 2020. We used generalized additive models to analyze the spatial distribution of SARS-CoV-2 positivity. Adjusted models included individual-level age, gender, and race, as well as neighborhood-level Area Deprivation Index, population density, demographic composition, and household size. Results Our dataset included 27 099 negative and 2039 positive unique SARS-CoV-2 tests. The odds of a positive SARS-CoV-2 test were higher for males (odds ratio [OR], 1.43; 95% credible interval [CI], 1.30–1.58), blacks (OR, 1.47; 95% CI, 1.27–1.70), and Hispanics (OR, 4.25; 955 CI, 3.55–5.12). Among neighborhood-level predictors, percentage of black population (OR, 1.14; 95% CI, 1.05–1.25), and percentage Hispanic population (OR, 1.23; 95% CI, 1.07–1.41) also influenced the odds of a positive SARS-CoV-2 test. Population density, average household size, and Area Deprivation Index were not associated with SARS-CoV-2 test results after adjusting for race. Conclusions The odds of testing positive for SARS-CoV-2 were higher for both black and Hispanic individuals, as well as within neighborhoods with a higher proportion of black or Hispanic residents—confirming that black and Hispanic communities are disproportionately affected by SARS-CoV-2. [ABSTRACT FROM AUTHOR]

Background: Tuberculosis is a known occupational hazard for healthcare workers (HCWs), especially in countries with a high burden of tuberculosis. It is estimated that HCWs have a 2- to 3-fold increased risk of developing tuberculosis compared with the general population. The objective of this study was to identify occupational risk factors for tuberculosis among HCWs in 3 district hospitals with specialized multidrug-resistant tuberculosis wards in KwaZulu-Natal, South Africa. Methods: We conducted a case-control study of HCWs diagnosed with tuberculosis between January 2006 and December 2010. Cases and controls were asked to complete a self-administered questionnaire regarding potential risk factors for tuberculosis. Results: Of 307 subjects selected, 145 (47%) HCWs responded to the questionnaire; 54 (37%) tuberculosis cases and 91 (63%) controls. Cases occurred more frequently among clinical staff 46% (n = 25) and support staff 35% (n = 19). Thirty-two (26% [32/ 125]) HCWs were known to be infected with human immunodeficiency virus (HIV), including 45% (21/54) of cases. HCWs living with HIV (odds ratio [OR], 6.35; 95% confidence interval [CI], 3.54–11.37) and those who spent time working in areas with patients (OR, 2.24; 95% CI, 1.40–3.59) had significantly greater odds of developing tuberculosis, controlling for occupation, number of wards worked in, and household crowding. Conclusions: HIV was the major independent risk factor for tuberculosis among HCWs in this sample. These findings support the need for HCWs to know their HIV status, and for HIV-infected HCWs to be offered antiretroviral therapy and isoniazid preventive therapy. Infection prevention and control should also be improved to prevent transmission of tuberculosis in healthcare settings to protect both HCWs and patients. [ABSTRACT FROM AUTHOR]

Background: Tobacco use is markedly higher among lesbian, gay, and bisexual populations than heterosexuals. Higher density of tobacco retailers is found in neighborhoods with lower income and more racial/ethnic minorities. Same-sex couples tend to live in similar neighborhoods, but the association of this demographic with tobacco retailer density has not been examined.Methods: For a national sample of 97 US counties, we calculated the number of tobacco retailers per 1000 persons and rates of same-sex couples per 1000 households in each census tract (n = 17 941). Using spatial regression, we examined the association of these variables in sex-stratified models, including neighborhood demographics and other environmental characteristics to examine confounding.Results: Results from spatial regression show that higher rates of both female and male same-sex couples were associated with a higher density of tobacco retailers. However the magnitude of this association was small. For female couples, the association was not significant after controlling for area-level characteristics, such as percent black, percent Hispanic, median household income, the presence of interstate highways, and urbanicity, which are neighborhood correlates of higher tobacco retailer density. For male couples, the association persisted after control for these characteristics.Conclusion: Same-sex couples reside in areas with higher tobacco retailer density, and for men, this association was not explained by neighborhood confounders, such as racial/ethnic composition and income. While lesbian, gay, and bisexual disparities in tobacco use may be influenced by neighborhood environment, the magnitude of the association suggests other explanations of these disparities remain important areas of research. [ABSTRACT FROM AUTHOR]

Background. The majority of Lyme disease cases in the United States are acquired on the east coast between northern Virginia and New England. In recent years the geographic extent of Lyme disease has been expanding, raising the prospect of Lyme disease becoming endemic in the southeast. Methods. We collected confirmed and probable cases of Lyme disease from 2000 through 2014 from the Virginia Department of Health and North Carolina Department of Public Health and entered them in a geographic information system. We performed spatial and spatiotemporal cluster analyses to characterize Lyme disease expansion. Results. There was a marked increase in Lyme disease cases in Virginia, particularly from 2007 onwards. Northern Virginia experienced intensification and geographic expansion of Lyme disease cases. The most notable area of expansion was to the southwest along the Appalachian Mountains with development of a new disease cluster in the southern Virginia mountain region. Conclusions. The geographic distribution of Lyme disease cases significantly expanded in Virginia between 2000 and 2014, particularly southward in the Virginia mountain ranges. If these trends continue, North Carolina can expect autochthonous Lyme disease transmission in its mountain region in the coming years. [ABSTRACT FROM AUTHOR]

Background. Genotyping Mycobacterium tuberculosis isolates allows study of dynamics of tuberculosis transmission, while geoprocessing allows spatial analysis of clinical and epidemiological data. Here, genotyping data and spatial analysis were combined to characterize tuberculosis transmission in Vitória, Brazil, to identify distinct neighborhoods and risk factors associated with recent tuberculosis transmission. Methods. From 2003 to 2007, 503 isolates were genotyped by IS6110 restriction fragment length polymorphism (RFLP) and spoligotyping. The analysis included kernel density estimation, K-function analysis, and at test distance analysis. Mycobacterium tuberculosis isolates belonging to identical RFLP patterns (clusters) were considered to represent recent tuberculosis infection (cases). Results. Of 503 genotyped isolates, 242 (48%) were categorized into 70 distinct clusters belonging to 12 RFLP families. The proportion of recent transmission was 34.2%. Kernel density maps indicated 3 areas of intense concentration of cases. K-function analysis of the largest RFLP clusters and families showed they co-localized in space. The distance analysis confirmed these results and demonstrated that unique strain patterns (controls) randomly distributed in space. A logit model identified young age, positive smear test, and lower Index of Quality of Urban Municipality as risk factors for recent transmission. The predicted probabilities for each neighborhood were mapped and identified neighborhoods with high risk for recent transmission. Conclusions. Spatial and genotypic clustering of M. tuberculosis isolates revealed ongoing active transmission of tuberculosis caused by a small subset of strains in specific neighborhoods of the city. Such information provides an opportunity to target tuberculosis transmission control, such as through rigorous and more focused contact investigation programs. [ABSTRACT FROM AUTHOR]

Background The adverse impact of Plasmodium vivax on child health beyond acute febrile illness is poorly studied. The effect of vivax malaria on child growth was evaluated and compared with diarrhoeal disease and non-specific fever.Methods Using data from a 43-month longitudinal cohort of children 0–72 months of age (n = 442) in the Peruvian Amazon, ponderal and linear growth velocities over 2-, 4- and 6-month periods were examined using longitudinal models and related to the incidence of disease during the same period.Results An episode of vivax malaria led to 138.6 g (95% confidence interval (CI) 81.9–195.4), 108.6 g (62.8–153.2) and 61 g (20.9–101.1) less weight gain over 2-, 4- and 6-month intervals, respectively. These deficits were larger than both diarrhoea (21.9, 17.2 and 13.8 g less weight gain, respectively) and fever (39.0, 30.3 and 25.6 g less weight gain, respectively). An incident episode of vivax also led to 0.070 cm (0.004–0.137) and 0.083 cm (0.015–0.151) less linear growth over 4 and 6 months, respectively, which were also larger than deficits from diarrhoea (0.029 and 0.028 cm, respectively) and fever (not associated with linear growth deficits). Despite the larger effect of P. vivax incident episodes on growth of a particular child, diarrhoeal disease had a larger cumulative impact on growth deficits as diarrhoeal incidence rates in this community are >10-fold higher than vivax malaria.Conclusions Disease control measures for vivax malaria and diarrhoeal disease have the potential to improve the growth of children in endemic areas. [ABSTRACT FROM AUTHOR]

Control of vaccine-preventable diseases depends on maintaining high levels of immunization coverage. Immunization coverage among preschool children remains suboptimal in some areas and sociodemographic subgroups, as well as for more recently introduced vaccines, leaving susceptible young children vulnerable to complications from vaccine-preventable diseases. This paper reviews approaches historically used to measure immunization coverage among preschool children in the United States. The strengths and weaknesses of various approaches to measuring immunization coverage among preschool children are explored, with emphasis on the current means to measure national immunization coverage—the National Immunization Survey. Methods for measuring immunization coverage among preschool children at local and state levels are also evaluated. Future opportunities and challenges for measuring immunization coverage at the local, state, and national levels are explored. [ABSTRACT FROM PUBLISHER]

Studies of diarrheal etiology in low- and middle-income countries have typically focused on children presenting with severe symptoms to health centers and thus are best equipped to describe the pathogens capable of leading to severe diarrheal disease. The Etiology, Risk Factors and Interactions of Enteric Infections and Malnutrition and the Consequences for Child Health and Development (MAL-ED) cohort study was designed to evaluate, via intensive community surveillance, the hypothesis that repeated exposure to enteropathogens has a detrimental effect on growth, vaccine response, and cognitive development, which are the primary outcome measures for this study. In the setting of multiple outcomes of interest, a longitudinal cohort design was chosen. Because many or even the majority of enteric infections are asymptomatic, the collection of asymptomatic surveillance stools was a critical element. However, capturing diarrheal stools additionally allowed for the determination of the principle causes of diarrhea at the community level as well as for a comparison between those enteropathogens associated with diarrhea and those that are associated with poor growth, diminished vaccine response, and impaired cognitive development. Here, we discuss the analytical methods proposed for the MAL-ED study to determine the principal causes of diarrhea at the community level and describe the complex interplay between recurrent exposure to enteropathogens and these critical long-term outcomes. [ABSTRACT FROM AUTHOR]

Most vaccine assessments have occurred in well-nourished populations of higher socioeconomic status. However, vaccines are often used in populations with high incidences of malnutrition and infections, in whom the effectiveness of some vaccines is inferior for unknown reasons. The degree and extent of vaccine underperformance have not been systematically studied for most vaccines across differing epidemiologic settings. This paper outlines the methods used and challenges associated with measuring immunological responses to oral vaccines against poliovirus and rotavirus, and parenteral vaccines against pertussis, tetanus, and measles in an observational study that monitored daily illness, monthly growth, intestinal inflammation and permeability, pathogen burden, dietary intake, and micronutrient status in children in 8 countries. This evaluation of vaccine response in the context of low- and middle-income countries is intended to address the gaps in knowledge of the heterogeneity in vaccine response in diverse epidemiological settings and the interplay between infections, nutrition, and immune response. [ABSTRACT FROM AUTHOR]