Implementing poultry vaccination and biosecurity at the village level in Tanzania: a social strategy to promote health in free-range poultry populations.

A social strategy was tested for implementing Newcastle disease (ND) vaccination and biosecurity improvements among free-ranging chicken at village level in Tanzania. In addition to training the local poultry vaccinators, data recorders and poultry-keepers, the strategy involved training and empowering leaders at the district, ward and village level. The trainings covered poultry health, management, and marketing of village chickens, with an emphasis on ND vaccination and improving biosecurity against avian influenza (AI), The study sites included villages in one ward in each of three each three districts (Iringa, Mtwara-Mikindani, and Mvomero) of mainland Tanzania. Ninety-six local leaders at district level and 101 leaders at ward levels were trained. In addition, 196 farmers (households) were trained, as well as 86 vaccinators and 26 data recorders. Data recorders were also trained as poultry first aid workers. ND vaccination was conducted by the vaccinators, supervised by their local leaders with technical assistance from veterinarians. A total of 158,343 village chickens were vaccinated in three rounds of vaccination three months apart. The training and empowerment of local leaders and local implementers was the key element for success as it fostered the feeling of local ownership of the program and prevented conflicts with other development activities within the villages. We conclude that most animal health programs will increase their odds of success by involving local leaders and by addressing the current challenges facing the farmers. Further assessment on the usefulness of this approach is needed.

Mosquito larval productivity in rice-fields infested with Azolla in Mvomero District, Tanzania.

Azolla (Salviniales: Azollaceae) is known to reduce oviposition and adult emergence of a number of mosquito species. Several species of Azolla are reportedly indigenous to Tanzania. However, the potential of Azolla as a biocontrol agent against malaria mosquitoes has not been evaluated in the country. This cross-sectional study was carried out to assess mosquito larval productivity in irrigated rice-fields infested with Azolla in Mvomero District, Tanzania. A systematic larval sampling covering all open water bodies along designed transect was carried in rice-fields. Larval density was estimated by dipping water bodies with or without Azolla. The degree of Azolla coverage was categorized as 0%, <50%, 50%, and >80%. Larvae densities were categorised as low (<50/m2), medium (50-500/m2) and high (> or = 500/m2) productivity. A total of 120 water bodies were surveyed and 105 (87.5%) had Azolla microphyla and A. pinnata at varying degrees of coverage. Of the total 105 water bodies with Azolla, 80 (76.2%) had a green Azolla mat, and 25 (23.8%) a brown Azolla mat. Eighty-eight (73.3%) of the sites were infested with anophelines and 109 (90.8%) with culicine larvae. Seventy percent of all water bodies contained anophelines and culicines in sympatric breeding, while 20.8% and 3.3% had only culicines and anophelines, respectively. The majority (82%) of mosquito breeding sites were found in area with Azolla substrate. Mosquito larva productivity was low in sites with highest (>80%) Azolla coverage. Seventy-two (81.8%) of the anopheline and 90 (82.6%) culicine breeding sites were infested with Azolla. Water bodies infested with green Azolla were more productive than those covered by brown coloured Azolla substrates for both culicines (13%) and anophelines (8%). Of the 1537 field collected larvae that hatched to adult stage, 646 (42.03%) were Anopheles gambiae s.l., 42 (2.73%) were An. funestus and 769 (50.03%) were Culex quinquefasciatus. These findings suggest that the mosquito productivity is low when the Azolla coverage is high (>80%). The promotion of Azolla in mosquito control should take into consideration the degree of Azolla coverage.

A health-education intervention trial to reduce porcine cysticercosis in Mbulu District, Tanzania.

We conducted a randomised community controlled trial to estimate the effectiveness of health and pig-management education intervention in reducing the incidence rate of porcine cysticercosis caused by Taenia solium in Mbulu District, northern Tanzania, between April 2002 and July 2004. We included a random sample of 827 pig-keeping households from 42 randomly selected villages in our 27-month study. We collected baseline data on the prevalence of porcine cysticercosis based on lingual examination of live pigs, and pig-management and sanitation knowledge and practices based on questionnaire interviews and observations. We allocated 21 of the villages to the health-education intervention, developed with community participation; we used stratified randomisation to balance the village-level baseline prevalence of porcine cysticercosis. From July 2003 to March 2004 following the intervention, we gave each participant household a sentinel piglet to raise (the timing was balanced between the intervention groups). Knowledge about the transmission and prevention of porcine cysticercosis was improved >42% in both groups when measured 10-12 months post-intervention. There was no improvement in observed practices in either group throughout the study period. However, the intervention had a significant reduction in the reported cases of household consumption of infected pork (a reduction by 20%). The intervention was associated with a considerable decrease in the incidence rate of porcine cysticercosis (incidence rate ratio 0.57) as measured by antigen-ELISA in sentinel pigs. Public education could lead to a reduction of the risk of infection in humans.

Participatory involvement of farming communities and public sectors in determining malaria control strategies in Mvomero District, Tanzania.

Addressing the malaria-agriculture linkages requires a broad inter-disciplinary and integrated approach that involves farming communities and key public sectors. In this paper, we report results of participatory involvement of farming communities in determining malaria control strategies in Mvomero District, Tanzania. A seminar involving local government leaders, health and agricultural officials comprising of a total of 27 participants was held. Public meetings in villages of Komtonga, Mbogo, Mkindo, Dihombo and Luhindo followed this. Findings from a research on the impact of agricultural practices on malaria burden in the district were shared with local communities, public sector officials and other key stakeholders as a basis for a participatory discussion. The community and key stakeholders had an opportunity to critically examine the linkages between agricultural practices and malaria in their villages and to identify problems and propose practical solutions. Several factors were identified as bottlenecks in the implementation of malaria control in the area. Lack of community participation and decision making in malaria interventions was expressed as among the major constraints. This denied the community the opportunities of determining their health priorities and accessing knowledge needed to effectively implement malaria interventions. In conclusion, this paper emphasizes the importance of participatory approach that involves community and other key stakeholders in malaria control using an ecosystem approach. An interdisciplinary and integrated approach is needed to involve farmers and more than one sector in malaria control effort.