Dataset Information

Integrating social contact and environmental data in evaluating tuberculosis transmission in a South African township.

ABSTRACT:

Background

Population models of tuberculosis transmission have not accounted for social contact structure and the role of the environment in which tuberculosis is transmitted.

Methods

We utilized extensions to the Wells-Riley model of tuberculosis transmission, using exhaled carbon dioxide as a tracer gas, to describe transmission patterns in an endemic community. Drawing upon social interaction data and carbon dioxide measurements from a South African township, we created an age-structured model of tuberculosis transmission in households, public transit, schools, and workplaces. We fit the model to local data on latent tuberculosis prevalence by age.

Results

Most tuberculosis infections (84%) were estimated to occur outside of one's own household. Fifty percent of infections among young adults (ages 15-19) occurred in schools, due to high contact rates and poor ventilation. Despite lower numbers of contacts in workplaces, assortative mixing among adults with high rates of smear-positive tuberculosis contributed to transmission in this environment. Households and public transit were important sites of transmission between age groups.

Conclusions

Consistent with molecular epidemiologic estimates, a minority of tuberculosis transmission was estimated to occur within households, which may limit the impact of contact investigations. Further work is needed to investigate the role of schools in tuberculosis transmission.

SUBMITTER: Andrews JR

PROVIDER: S-EPMC4133578 | biostudies-literature | 2014 Aug

REPOSITORIES: biostudies-literature

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Publications

Integrating social contact and environmental data in evaluating tuberculosis transmission in a South African township.

Andrews Jason R JR Morrow Carl C Walensky Rochelle P RP Wood Robin R

The Journal of infectious diseases 20140308 4

<h4>Background</h4>Population models of tuberculosis transmission have not accounted for social contact structure and the role of the environment in which tuberculosis is transmitted.<h4>Methods</h4>We utilized extensions to the Wells-Riley model of tuberculosis transmission, using exhaled carbon dioxide as a tracer gas, to describe transmission patterns in an endemic community. Drawing upon social interaction data and carbon dioxide measurements from a South African township, we created an age- ...[more]

PMID: 24610874

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Project description:BackgroundIn 2004, the Ministry of Health issued the policy of decentralising microscopy services (MCs) to one third of all township hospitals in China. The study was conducted in Gansu Province, a poor western one in China. Ganzhou was one county in Gansu Province. Ganzhou County was identified as a unique case of further decentralisation of tuberculosis (TB) treatment services in township hospitals. The study evaluated the impact of the MC policy on providers and patients in Gansu Province. The second objective was to assess the unique case of Ganzhou County compared with other counties in the province.MethodsBoth quantitative and qualitative methods were used. All 523 MCs in the province completed an institutional survey regarding their performance. Four counties were selected for in-depth investigation, where 169 TB suspects were randomly selected from the MC and county TB dispensary registers for questionnaire surveys. Informant interviews were conducted with 38 health staff at the township and county levels in the four counties.ResultsGansu established MCs in 39% of its township hospitals. From January 2006 to June 2007, 8% of MCs identified more than 10 TB sputum smear positive patients while 54% did not find any. MCs identified 1546 TB sputum smear positive patients, accounting for 9% of the total in the province. The throughputs of MCs in Ganzhou County were eight times of those in other counties. Interviews identified several barriers to implement the MC policy, such as inadequate health financing, low laboratory capacity, lack of human resources, poor treatment and management capacities, and lack of supervisions from county TB dispensaries.ConclusionMicroscopy centre throughputs were generally low in Gansu Province, and the contribution of MCs to TB case detection was insignificant taking account the number of MCs established. As a unique case of full decentralisation of TB service, Ganzhou County presented better results. However, standards and quality of TB care needed to be improved. The MC policy needs to be reviewed in light of evidence from this study.

Dataset Information

Integrating social contact and environmental data in evaluating tuberculosis transmission in a South African township.

Background

Methods

Results

Conclusions

Publications

Integrating social contact and environmental data in evaluating tuberculosis transmission in a South African township.

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