[Variability in urban malaria transmission across health districts in Bouaké, Côte d'Ivoire].

RATIONALE: Approximately 20 years ago, studies conducted in the city of Bouaké revealed a high level of malaria transmission, primarily due to the Anopheles gambiae vector increasing during the rainy season. The National Malaria Control Program implemented control efforts involving the distribution of long-lasting insecticidal nets (LLINs). However, the political and military crisis from 2002 to 2011 caused many residents to leave the city, leaving the natural environment largely undisturbed. The subsequent return of the population to Bouaké necessitated implementing new LLIN-based control programs. New research studies are needed to collect data on malaria transmission parameters. This study is conducted within this context. The objective is to assess vector-borne malaria transmission by determining entomological parameters in the city's three health districts.

MATERIALS AND

METHODS

Investigations were conducted in urban areas during the rainy season from June 10 to 29, 2016, in Bouaké's three health districts (Northwest, Northeast, and South). Mosquitoes were collected from human-biting samples and identified. We examined the feeding behavior of female vectors and estimated the entomological parameters of malaria transmission. We determined the physiological age of the female vectors by dissecting their ovaries and detected mosquitoes infected with Plasmodium falciparum using the ELISA-CSP test.

RESULTS

Only the malaria vector species An. gambiae was collected. The species exhibited a tendency toward endophagy and had an average parturition rate exceeding 90% in all districts. Aggressive densities of the species were 3.6, 15.5, and 14.4 bites/ person/night (b/p/n) in the Northwest, Northeast, and South districts, respectively. The infection rates were 4.2%, 2.9%, and 1.9% in the Northwest, Northeast, and South districts, respectively, with entomological inoculation rates of 0.15, 0.45, and 0.22 b/p/n.

CONCLUSION

Malaria transmission occurs in all three districts of Bouaké, with levels twice as high in the Northeast District. This transmission is carried out by the An. gambiae species, which exhibited a tendency toward endophagous feeding at all sites.