Establishing and implementing Demographic Surveillance System as a tool for monitoring health interventions in Korogwe District, north-eastern Tanzania

Abstract

In the Korogwe demographic surveillance system (DSS) site in north-eastern Tanzania, information on vital events such as births, deaths and migration has been collected since its establishment in 2005. The aim was to obtain demographic and epidemiological indices to be used in the evaluation of health related interventions which have been undertaken in the area. Period covered is up to December 2010. Baseline survey was conducted in 14 villages of Korogwe district in October 2005 and DSS was launched in January 2006. Demographic, social economic status, immunisation coverage and birth history data was collected during the follow-up and each household was visited every 4 months. Estimates of mortality levels were derived from deaths that were collected during household visits. Birth history data were used to estimate the lifetime and period fertility of women aged 15-49. Estimates of crude migration and age specific migration rates were derived from the number of people moving in or out of the DSS site and the person-years lived. The population at baseline survey was 25,264 individuals in 5,853 households. The percentage of deaths was higher among adult aged 15-60 years compared to other age groups. The probability of dying among males (376/1000) aged 15-60 was higher than females (339/1000) in the same age group. The lifetime and period fertility estimates were 5.6 and 5.1 children per woman respectively. Women aged 30-34 are expected to have 3-4 children at the end of their childbearing age. Migration were higher at the youngest ages, lower rates at the 10-14 age groups, a peak at the 20-24 ages, and a gradual decline up to the oldest ages. Majority of households in rural areas 51.8% were l in low socio-economic status compared to 40.3% in urban areas which were in high socio-economic status. About 74% and 55.5% of the children received BCG and measles vaccination, respectively. In conclusion, Korogwe DSS has provided useful data which was utilised in planning malaria vaccine trials. Findings from the DSS will also be used in planning of future clinical trials and by the District authorities as input for health and other development planning purposes, including setting of crucial priorities.