Impact of Mass Distribution of Long-Lasting Insecticide Nets on Malaria Prevention in Lindi Region, Tanzania: A quasi experimental study

Abstract Background Malaria is a major public health issue with high rates of morbidity and mortality in the United Republic of Tanzania. To ensure that all households remain protected, national malaria control programs and partners in 2022 implemented free mass distribution of long-lasting insecticides nets to population at risk and high prevalent regions with malaria including Lindi region. The present study aimed to assess the effectiveness of free long-lasting insecticide-treated nets in reducing malaria burden among the population. Methods we conducted a quasi-experimental study from September 2021 to August 2022 and September 2022 to August 2023. The data were collected on District Health Information System version two in Lindi region and analysed with T-tests to compare the malaria positive rate before (September 2021 to August 2022) and after the distribution of long-lasting insecticides nets (September 2022 to August 2023). Malaria positive rate in the general population who attended outpatient department was reduced by 7.6% after distribution of long-lasting insecticides nets. A comparison of malaria cases recorded between September 2021 and August 2023 in the different area showed disparities. Before long lasting insecticides nets implementation, the malaria positive rate in all area combined was 20.6%. Whereas malaria positive rate in all area combined was 13% after implementation. The mean difference is 6.60, with a standard deviation of 2.47. The t-value is 6.55, with 5 degrees of freedom. The significance (2-tailed) value is <0.001, indicating a statistically significant difference between the malaria positive rate before and after long lasting insecticides nets implementation. Conclusion the long-lasting insectides nets distribution campaign synergy with other preventive interventions has had a significant impact on reducing the malaria positive rate in the population.