Household contacts of active TB cases are at increased risk of TB infection and several studies have measured TB prevalence in this key population. The study described here not only measured TB prevalence, but also measured TB and HIV incidence in the household contacts of 729 TB index cases in the Matlosana sub-district in North West Province. We concluded that the efficacy of contact tracing for TB control purposes might be improved by a second intensified case finding visit and by providing preventive treatment against TB for both HIV-infected and HIV-seronegative household contacts of TB cases.
Cari van Schalkwyk
In 2011, the Ministry of Health in Swaziland joined forces with the WHO, the Global Fund and SACEMA to do the first in depth health programmes progress evaluation using triangulation from key empirical data sources. The focus was on key questions like: Given increasing coverage of ART, has ART reduced adult and/or infant mortality?; Can TB trends be related to trends in HIV prevalence, ART coverage and combined TB/HIV interventions?; Can trends in infant mortality be related to uptake of PMTCT?
SACEMA presented modelling work on e.g. incidence and prevalence of HIV at the two recent HIV and AIDS conference.
Robust affordable means for estimating HIV incidence at the population level continue to be elusive and much desired. As resources are invested in developing more appropriate tests for recent infection, the methods for evaluating and optimising the performance of candidate tests need to be further refined. We have recently explored a range of statistical methods for estimating the mean duration of recent infection (MDRI) by investigating a data set from Harare, Zimbabwe. We investigated whether there is an optimum way of estimating the mean recency duration for this dataset. We also ask how estimates of the mean recency duration and incidence are affected by our choice of cut-off and whether these effects differ with our choice of estimation method.