Spatial and temporal variation in malaria transmission in a low endemicity area in northern Tanzania.

BACKGROUND: Spatial and longitudinal monitoring of transmission intensity will allow better targeting of malaria interventions. In this study, data on meteorological, demographic, entomological and parasitological data over the course of a year was collected to describe malaria epidemiology in a single village of low transmission intensity. METHODS: Entomological monitoring of malaria vectors was performed by weekly light trap catches in 10 houses. Each house in the village of Msitu wa Tembo, Lower Moshi, was mapped and censused. Malaria cases identified through passive case detection at the local health centre were mapped by residence using GIS software and the incidence of cases by season and distance to the main breeding site was calculated. RESULTS: The principle vector was Anopheles arabiensis and peak mosquito numbers followed peaks in recent rainfall. The entomological inoculation rate estimated was 3.4 (95% CI 0.7-9.9) infectious bites per person per year. The majority of malaria cases (85/130) occurred during the rainy season (chi2 = 62,3, p < 0.001). Living further away from the river (OR 0.96, CI 0.92-0.998, p = 0.04 every 50 m) and use of anti-insect window screens (OR 0.65, CI 0.44-0.94, p = 0.023) were independent protective factors for the risk of malaria infection. Children aged 1-5 years and 5-15 years were at greater risk of clinical episodes (OR 2.36, CI 1.41-3.97, p = 0.001 and OR 3.68, CI 2.42-5.61, p < 0.001 respectively). CONCLUSION: These data show that local malaria transmission is restricted to the rainy season and strongly associated with proximity to the river. Transmission reducing interventions should, therefore, be timed before the rain-associated increase in mosquito numbers and target households located near the river.

Quantitative validation of media for transportation and storage of Streptococcus pneumoniae.

The need to design effective Streptococcus pneumoniae vaccines and to monitor resistance means that it is essential to have efficient methods to determine carriage rates. Two liquid media, consisting of skim milk, glycerol, glucose, and tryptone soya broth (STGG) or skim milk, glycerol, and glucose (SGG) alone, were evaluated for their ability to maintain pneumococcal viability. Optimal recovery of S. pneumoniae was achieved when swabs were transferred to STGG medium prior to plating onto blood agar-gentamicin selective plates (22%) compared to 7% when plated out directly (P < 0.0001 by Fisher's exact test). Both STGG and SGG media are appropriate for the long-term storage of pneumococci and primary swab samples at -70 degrees C, with no decrease in viable count observed following repeated freeze-thaw cycles. Samples could be stored refrigerated for up to 3 days in either STGG or SGG medium with no significant loss of viability. Viability decreased progressively in storage at 20 to 30 degrees C, with greater losses of viability occurring at the higher temperatures. There were no significant differences in viability between isolates in the two media. STGG preserved pneumococci significantly better (about twofold) than SGG medium at 21 degrees C (P < 0.0001) and 30 degrees C (P < 0.0001). Samples can be stored for 4 and 2.5 days at 6 to 8 degrees C, 28 and 17 h at 21 degrees C, and 15 and 7 h at 30 degrees C in STGG and SGG media, respectively. For field studies undertaken in resource-limited environments, SGG medium can be prepared by using locally available materials. The quantitative data reported in this study will enable researchers to plan appropriate transport and storage protocols.

Community participation in integrated projects.

PIP: The top 10 advantages of community participation in integrated projects are outlined, from experience gleaned in Tanzania and discussed at the Second National Workshop. Integrated projects succeed if they involve the community because they evoke self-imposed permanent changes, community acceptance, and harmony between the project leader and the community members. People feel a sense of ownership, achieve positive attitudes and awareness. Utilization of community resources, accessibility to those in need, affordability and wide coverage are more likely if the people are involved in planning. Feedback between service donors and service recipients becomes well established. Finally, community participation leads to a humanistic approach, and confers dignity and respect. The community itself knows best how to be served, and its active participation is inevitable and mandatory in achieving project goals.^ieng