Project Lead(s): Fredros Okumu
In rice-growing communities in Sub-Sahara Africa, the risk of mosquito bites and mosquito-borne illnesses is a major concern, as the associated land-use practices usually lead to high and sustained mosquito breeding.
Every year, thousands of subsistence rice farmers in rural Africa relocate for many months to tend to rice fields in distant river valleys, far from health facilities, bringing along young children and infants.
They live in improvised, semi-open shacks that cannot be readily fitted with mosquito nets or sprayed with residual insecticides, leaving them more exposed to mosquito-borne illnesses.
Implemented in southeastern Tanzania, the project involved development of a portable, low-cost, mosquito-proof hut that can protect migratory rice farmers from mosquitoes.
A prototype of the hut was produced with the help of a local manufacturing company, called Elastic Products Limited.
The prototypes were developed after a cross-sectional entomological survey to quantify and compare actual mosquito bite exposure between the temporary structures used in the farms and in their regular homes.
Mosquitoes were collected from indoor and outdoor sampling, and sorted by species and blood feeding status (gravid, blood-fed or unfed).
Anopheles gambiae and Anopheles funestus were sub-sampled for polymerase chain reaction (PCR) to identify sibling species and enzyme immunosorbent assays (ELISA) to determine plasmodium infection rates.
From the four villages studied, average indoor densities of different female mosquito species for 20 sentinel main houses (n = 155) were as follows: 14.6 female Anopheles gambiae s.l., 4.7 female Anopheles funestus, 22.5 female Culex species, 1.6 female Mansonia species.
For the 20 sentinel Shamba houses (n = 160), the mean catches were 22.7 An. gambiae, 11.6 An. funestus, 14.6 Culex species and 1.8 Mansonia species.
The prototype reduced the indoor densities of mosquitoes, as no mosquitoes were caught inside the prototype huts.
The new hut designs also allow for other tools (like bed nets and indoor residual sprays) to be used and will lead to the farmers reducing the amount of time they spend outdoors, thus avoiding further exposure.
People enthusiastically accepted the huts and showed interest in purchasing them.
The team feels the huts could be one of the new tools that could be used to effectively close the gap in controlling residual mosquito-borne disease transmission in disenfranchised migratory communities, like rice farmers.