A Comparative Study of the Risk Factors of Malaria within Urban and Rural Settings in the Sahelian Region of Cameroon and the Role of Insecticide Resistance in Mosquitoes

Background: Cameroon is among the 11 countries that account for 92 % of malaria infection in sub-Saharan-Africa in 2018, and Maroua III Health District and her environs witnessed a malaria outbreak in 2013 with hundredths of deaths.

Aim: To determine the risk factors of malaria in the urban and rural population and to investigate the level of mosquito’s resistance to Deltamethrin and Permethrin.

Methods: It was a cross-sectional community-based study carried out in August, September and October 2019, in which questionnaires were administered to 500 participants, to obtain information on demographics, socioeconomics, behavioral, and environmental factors thought to be associated with malaria infection in both rural and urban settings. Blood samples were collected for diagnosis of malaria and bivariate and multivariate regression analysis were used to identify risk factors of malaria. Mosquito resistance to Deltamethrin and Permethrin were determined using the CDC Bottle Bioassay test.

Results: Malaria prevalence was 52.2 % which was significantly higher (P = 0.016) in rural areas (57.6%) than urban areas (46.8%). The prevalence of asymptomatic malaria was 43.4% and the geometric mean parasite density was 6333.60 parasites/µL of blood. Malaria infection was significantly (P<0.001) associated with children (64.1%) and teenagers (58.1%). Likewise, the infection was significantly associated with the presence of crops around homes (P=0.031), usage of old LLINs for more than three years and in urban settings, with primary education level (P=0.023). The overall mortality of Anopheles species was 93.57% (91.19% in rural and 95.83% in urban areas) for deltamethrin which was more sensitive than 83.85% (85.24% in rural and 82.46% in urban areas) for permethrin.

Conclusion: Relevant data for malaria control in Maroua III health district, a typical Sahelian environment has been generated, and indicates that most of the burden of malaria is borne by children and teenagers.