The use of community-based animal health workers to strengthen disease surveillance systems in Tanzania.

An 18 month trial was conducted in three districts of Arusha region, northern Tanzania, to assess the use of community-based animal health workers (CAHWs) in an official disease surveillance system. Disease reports provided by CAHWs were assessed using six indicators for effective disease surveillance, i.e. sensitivity, specificity, timeliness, representativeness, simplicity and acceptability. To assess sustainability issues and determine the incentives required by CAHWs to report disease, three different incentive models were tested in the trial. None of the incentive models involved direct payments to CAHWs. Before involving CAHWs in disease surveillance in the three trial districts, disease case reports as a proportion of cattle population were 0.13%, 0.20% and 0.12%. During the trial, disease case reports as a proportion of cattle population increased to 5.0%, 5.6% and 6.3%. The CAHWs also improved the spatial and temporal coverage of the disease surveillance system and provided timely reports. During the trial, national-level disease reporting in Tanzania increased by 17% owing to the sensitisation and support activities of the Pan African Programme for the Control of Epizootics in Tanzania. In Arusha region, disease reporting increased by 118%, and 49% of this improvement was attributable to increased reporting in the three trial districts. Reporting from these districts far exceeded that from any other district in Tanzania. Veterinarians confirmed the CAHWs' clinical diagnosis in 88% of the 170 clinical cases examined. The increase in disease reporting resulting from CAHW activities was sufficient to enable the national epidemiology unit to achieve its target in relation to World Organisation for Animal Health (OIE) guidelines. The authors conclude that the use of CAHWs should be promoted in the national strategy for disease reporting. Additionally, CAHWs must be brought under the control of the Tanzanian veterinary authorities, a process that will include appropriate legislative reform.