Investigating spillover of multidrug-resistant tuberculosis from a prison: a spatial and molecular epidemiological analysis.

BACKGROUND: Congregate settings may serve as institutional amplifiers of tuberculosis (TB) and multidrug-resistant tuberculosis (MDR-TB). We analyze spatial, epidemiological, and pathogen genetic data prospectively collected from neighborhoods surrounding a prison in Lima, Peru, where inmates experience a high risk of MDR-TB, to investigate the risk of spillover into the surrounding community. METHODS: Using hierarchical Bayesian statistical modeling, we address three questions regarding the MDR-TB risk: (i) Does the excess risk observed among prisoners also extend outside the prison? (ii) If so, what is the magnitude, shape, and spatial range of this spillover effect? (iii) Is there evidence of additional transmission across the region? RESULTS: The region of spillover risk extends for 5.47 km outside of the prison (95% credible interval: 1.38, 9.63 km). Within this spillover region, we find that nine of the 467 non-inmate patients (35 with MDR-TB) have MDR-TB strains that are genetic matches to strains collected from current inmates with MDR-TB, compared to seven out of 1080 patients (89 with MDR-TB) outside the spillover region (p values: 0.022 and 0.008). We also identify eight spatially aggregated genetic clusters of MDR-TB, four within the spillover region, consistent with local transmission among individuals living close to the prison. CONCLUSIONS: We demonstrate a clear prison spillover effect in this population, which suggests that interventions in the prison may have benefits that extend to the surrounding community

Evidence for heterogeneity in China’s progress against pulmonary tuberculosis: uneven reductions in a major center of ongoing transmission, 2005–2017

Abstract Background China contributed 8.9% of all incident cases of tuberculosis globally in 2017, and understanding the spatiotemporal distribution of pulmonary tuberculosis (PTB) in major transmission foci in the country is critical to ongoing efforts to improve population health. Methods We estimated annual PTB notification rates and their spatiotemporal distributions in Sichuan province, a major center of ongoing transmission, from 2005 to 2017. Time series decomposition was used to obtain trend components from the monthly incidence rate time series. Spatiotemporal cluster analyses were conducted to detect spatiotemporal clusters of PTB at the county level. Results From 2005 to 2017, 976,873 cases of active PTB and 388,739 cases of smear-positive PTB were reported in Sichuan Province, China. During this period, the overall reported incidence rate of active PTB decreased steadily at a rate of decrease (3.77 cases per 100,000 per year, 95% confidence interval (CI): 3.28–4.31) that was slightly faster than the national average rate of decrease (3.14 cases per 100,000 per year, 95% CI: 2.61–3.67). Although reported PTB incidence decreased significantly in most regions of the province, incidence was observed to be increasing in some counties with high HIV incidence and ethnic minority populations. Active and smear-positive PTB case reports exhibited seasonality, peaking in March and April, with apparent links to social dynamics and climatological factors. Conclusions While PTB incidence rates decreased strikingly in the study area over the past decade, improvements have not been equally distributed. Additional surveillance and control efforts should be guided by the seasonal-trend and spatiotemporal cluster analyses presented here, focusing on areas with increasing incidence rates, and updated to reflect the latest information from real-time reporting.https://deepblue.lib.umich.edu/bitstream/2027.42/152198/1/12879_2019_Article_4262.pd

The impact of environmental and climatic variation on the spatiotemporal trends of hospitalized pediatric diarrhea in Ho Chi Minh City, Vietnam.

It is predicted that the integration of climate-based early warning systems into existing action plans will facilitate the timely provision of interventions to diarrheal disease epidemics in resource-poor settings. Diarrhea remains a considerable public health problem in Ho Chi Minh City (HCMC), Vietnam and we aimed to quantify variation in the impact of environmental conditions on diarrheal disease risk across the city. Using all inpatient diarrheal admissions data from three large hospitals within HCMC, we developed a mixed effects regression model to differentiate district-level variation in risk due to environmental conditions from the overarching seasonality of diarrheal disease hospitalization in HCMC. We identified considerable spatial heterogeneity in the risk of all-cause diarrhea across districts of HCMC with low elevation and differential responses to flooding, air temperature, and humidity driving further spatial heterogeneity in diarrheal disease risk. The incorporation of these results into predictive forecasting algorithms will provide a powerful resource to aid diarrheal disease prevention and control practices in HCMC and other similar settings

Integrating Social and Biological Processes of Infectious Disease Transmission at Three Levels: Household, Community and Region.

This dissertation addresses infectious disease transmission at several levels: within households, communities, and villages within a region. At each level, we consider the elements of social behavior and social structure relevant for understanding infectious disease transmission dynamics and risk of infection. In the first chapter, which focuses on the household level, we analyze a series of household outbreaks of norovirus (NoV), a common gastrointestinal pathogen. This paper takes advantage of a natural experiment in which many households were infected at once after exposure to an infectious food-handler. This allows us to examine within-household transmission in a way that is separated from other social processes. In the second paper, we focus on community level norovirus transmission, incorporating insights from the household-level analysis in paper one with empirical data on social processes. We focus specifically on age-structured contact patterns in order to build a community-wide model of norovirus transmission. This model sheds light on the role social behavior plays in the community-level epidemiology of gastrointestinal pathogens. Finally, in the third paper, we focus at the geographic regional level, examining the risk of gastrointestinal illness across communities. This paper looks at how variability in remoteness and community-wide social networks impacts risk of gastrointestinal illness in a group of 19 villages in rural, northern coastal Ecuador. Taken together, these papers address a number of theoretical and methodological issues that are important to both the epidemiology of infectious diseases and the sociology of health and illness.Ph.D.Public Policy & SociologyUniversity of Michigan, Horace H. Rackham School of Graduate Studieshttp://deepblue.lib.umich.edu/bitstream/2027.42/84643/1/jzelner_1.pd

Parameters and definitions.

<p>The table lists parameters used in each model as well as fixed values and ranges of parameters assumed or estimated separately from the current analysis. Entries marked ‘EST’ indicate parameters estimated in the analysis. Model-specific parameters are denoted by a subscript.</p

Descriptive characteristics of household outbreak data compared to 10?4 simulations from fitted Models 1–3.

<p>Descriptive characteristics of household outbreak data compared to 10?4 simulations from fitted Models 1–3.</p

Observations for 18 households with non-index cases.

<p>The figure illustrates the time course of infection in the 18 households in which there was a non-index case who became ill after the onset of symptoms in the index case. Filled boxes indicate an individual who dined at the point-source and became ill. Filled circles indicate individuals who became ill and did not dine at the point-source. Hollow boxes and circles along the right margin indicate the number of individuals in the household who did and did not dine at the point source and did not become ill, respectively. The additional 52 households in the analysis with no secondary cases are not pictured.</p

Parameter estimates for Models 1–3.

<p>Parameter estimates for Models 1–3.</p

Bacillus Calmette-Guérin and Isoniazid Preventive Therapy Protect Contacts of Patients with Tuberculosis

Rationale: Individuals living with patients with tuberculosis (TB) are at elevated risk of infection and disease, with children at greatest risk. The World Health Organization recommends isoniazid preventive therapy (IPT) for HIV-positive contacts and those younger than 5 years. Despite these recommendations, household-level IPT programs are rarely implemented in high TB burden settings. Evidence is scarce about the age-specific efficacy of interventions, such as IPT and bacillus Calmette-Guérin (BCG) vaccination for preventing TB disease among exposed contacts. Objectives: We estimate the age-specific efficacy of IPT and BCG for preventing TB disease using data from a large observational prospective cohort study of household contacts of patients with TB in Lima, Peru. Methods: We identified all adults ( \u3e 15 yr) with incident pulmonary TB (index cases) diagnosed at 106 public health centers in Lima from September 2009 to August 2012. Among 14,041 household contacts (of 3,446 index cases) assessed for infection and disease during the yearlong follow-up period, we identified 462 additional TB cases. We estimate risk ratios (RR) for pulmonary TB associated with BCG, IPT, and latent TB infection. Measurements and Main Results: BCG confers protection against coprevalent and incident TB among HIV-negative children younger than 10 years (RR, 0.35; 95% confidence interval, 0.19–0.66). IPT confers protection against incident TB among HIV-negative contacts younger than 30 years (RR, 0.33; 95% confidence interval, 0.20–0.54). Risk of incident TB associated with latent TB infection is greatest for children younger than 5 years and decreases with age. Conclusions: These findings support the use of IPT in older children and young-adult household contacts, in addition to children younger than 5 years

Evidence for heterogeneity in China's progress against pulmonary tuberculosis: uneven reductions in a major center of ongoing transmission, 2005-2017.

BackgroundChina contributed 8.9% of all incident cases of tuberculosis globally in 2017, and understanding the spatiotemporal distribution of pulmonary tuberculosis (PTB) in major transmission foci in the country is critical to ongoing efforts to improve population health.MethodsWe estimated annual PTB notification rates and their spatiotemporal distributions in Sichuan province, a major center of ongoing transmission, from 2005 to 2017. Time series decomposition was used to obtain trend components from the monthly incidence rate time series. Spatiotemporal cluster analyses were conducted to detect spatiotemporal clusters of PTB at the county level.ResultsFrom 2005 to 2017, 976,873 cases of active PTB and 388,739 cases of smear-positive PTB were reported in Sichuan Province, China. During this period, the overall reported incidence rate of active PTB decreased steadily at a rate of decrease (3.77 cases per 100,000 per year, 95% confidence interval (CI): 3.28-4.31) that was slightly faster than the national average rate of decrease (3.14 cases per 100,000 per year, 95% CI: 2.61-3.67). Although reported PTB incidence decreased significantly in most regions of the province, incidence was observed to be increasing in some counties with high HIV incidence and ethnic minority populations. Active and smear-positive PTB case reports exhibited seasonality, peaking in March and April, with apparent links to social dynamics and climatological factors.ConclusionsWhile PTB incidence rates decreased strikingly in the study area over the past decade, improvements have not been equally distributed. Additional surveillance and control efforts should be guided by the seasonal-trend and spatiotemporal cluster analyses presented here, focusing on areas with increasing incidence rates, and updated to reflect the latest information from real-time reporting