A controlled education intervention on proper mosquito net usage in Tanzania

Mass distribution campaigns have effectively dispersed 26.9 million long lasting insecticidal nets (LLINs) covering 89.6% of surveyed Tanzanians in 2012. Although net ownership is no longer a hurdle in malaria prevention, correct usage of nets remains an issue. Studies have suggested improper use behaviors such as leaving unrepaired holes, overwashing, seasonal use or neglecting vulnerable household members. In our study, households were randomized to an intervention and control group. Intervention participants (n=60) received an education consisting of a diagram, verbal explanation and physical demonstration of proper net use practices prior to a baseline questionnaire. Control participants (n=57) received the education after the two-week evaluation questionnaire. Paired t-tests were used to compare baseline and evaluation responses in both groups. Significant differences were found in the intervention group between pre- and post- test in: knowledge of using nets in protection from mosquitoes (p<0.0001), having no holes in net (p=0.002), daylong net use (p=0.002), not leaving net in the sun (p<0.0001) and less frequent washing of nets (p<0.0001). Differences were also found in the control group for: knowledge of nets in protection from mosquitoes (p<0.001), no holes in net (p<0.0001) and not leaving nets in the sun (p=0.016). Our findings suggest a crossover effect of the intervention with significant differences in the control group; this may be due to ineffective randomization. The study reinforces the lack of knowledge of free net recipients in proper net care and usage. Multi-faceted education demonstrating proper net use would be essential in accompanying free net distribution campaigns.