Malaria Control in KwaZulu-Natal: A comparison between insecticide-treated bednets and residual house spraying
The study aims at informing a policy decision on whether or not to replace insecticide house spraying with insecticide-treated bednets for malaria control in South Africa. In order to achieve this, there is a need to establish: the impact of bednets on malaria incidence reduction; their acceptability by communities who traditionally do not use them; how best to disseminate/distribute bednets and whether bednets are cheaper in comparison to traditional spraying of houses with insecticides.
A study involving about 14 000 people in KwaZulu-Natal compared the use of insecticide-treated bednets with traditional spraying of houses for malaria control. The study is a collaboration between the MRC and the Department of Health, Jozini and has policy implications for malaria control not only in South Africa but in the whole of southern Africa where malaria transmission is seasonal and insecticide house spraying has been the mainstay of vector control for over five decades.
Results
of the study in KwaZulu-Natal show that:
- Local communities preferred green and conical nets because they do not show dirt and are easy to hang - "You give people what they want"
- Assessment of people's knowledge, attitudes and practices towards bednets has indicated that communities have good knowledge about malaria and have accepted nets very well. They are using bednets consistently because of a perceived benefit "we no longer have to cover ourselves with blankets in summer"; they have treated their own bednets thus reducing the time it would have taken malaria control programme staff to spray their homes; we have recorded very low frequencies of net washing and in sprayed areas we have also reported increased demand for bednets
- In terms of impact on malaria overall, we have reported a significant reduction in malaria cases (31%) in areas with bednets as compared to those in sprayed areas where there was an 18% increase in malaria cases. Areas earmarked for bednets had a significantly higher malaria incidence before bednets were introduced
- Insecticide-treated bednets also caused a higher proportion of mosquitoes that were unable to bite people and those that attempted to bite were killed by the insecticide on the nets. These two factors contributed to the results on the reduction of malaria cases with bednets
- Preliminary results on costing show that bednets are cheaper than house spraying if spray teams are recruited for the whole year and not for the period of spraying only with greater savings for each case prevented
- The issue of whether or not communities can contribute towards the cost of nets and re-treatments is still being investigated.
Collaborators
Medical Research Council and the Malaria Control Programme in Jozini.
Funding
Medical Research Council and the Department of Health.
