Project Lead(s): Calister Imeda
Issue
Malaria is one of the major threats to public health and economic development and, in Tanzania, malaria is the leading cause of morbidity and mortality.
Conventional malaria vector control strategies, including integrated malaria vector control (IVM), using long-lasting insecticidal nets (LLINs), indoor residual spraying (IRS) and environmental management have been found to be effective.
However, the effectiveness of LLINs and IRS approaches targeting indoor biting mosquitoes in preventing malaria is threatened by the changing biting behaviour of mosquitoes from night and inside houses, to daylight and outside houses, and by their increasing resistance to insecticides.
Solution
This study was undertaken with the intent of repelling mosquitos around the houses, where people sit during evening hours.
The intervention used was planting lemon grass in pots around the houses. Lemon grass has long been used in natural insect repellents, which contain citronella oil.
Native to Asia, the grass can grow up to six feet tall and is quite an attractive ornamental grass. A total of 800 pots and seedlings were purchased and transported to the field sites. Transplanting seedlings to the pots was done in the sites, in collaboration with study participants.
The mosquito population in and around the houses was assessed by comparing the population of mosquitoes at the baseline and at the end of the study. Selection of villages considered prevalence of malaria among children below five years of age.
A total of 119 children participated in the study, with 114 available at the end of the study to be tested for malaria.
Twenty households were enrolled for mosquito collection.
Outcome
The study was not able to establish any reduction in the prevalence of malaria resulting from the presence of lemon grass.
A total of 5,203 and 3,897 female Culex quinquefasciatus mosquitoes were collected at baseline and at the end of the intervention respectively, which showed a significant change in the number of mosquito bites in the houses after the intervention.
After dissection, none of the captured mosquitos had filarial worms.
The team would like to expand the project to other villages in the district and intends to apply for Phase II Transition To Scale funding.
Funding will be needed to conduct community sensitization meetings, as well as to mass-produce seedlings for distribution to the communities.
The trend of malaria prevalence among community members will be measured, to continue monitoring the effect of lemon grass and possible emerging resistance.