Asymptomatic malaria: building bridges with communities through patients in Côte d’Ivoire

Abstract Background In malaria-endemic areas, asymptomatic carriers are a reservoir of parasites that contribue to the persistence of malaria transmission. In Côte d’Ivoire, this situation is poorly documented. The objective of our study was to assess the frequency and socio-environmental factors associated with asymptomatic malaria in the town of Assuefry, located in the northeast of Côte d’Ivoire, a region where malaria prevalence remains high. Methods A cross-sectional study in two stages was conducted from October to December 2018, first at the Urban Health Center (UHC) in Assuefry and then in the households. The sample size calculated for patients was 162 extrapolated to 201 people. All persons received at the CSU who had clinical symptoms of malaria and a positive Rapid Diagnostic Test (RDT) were included. In the households of these index subjects, a follow-up survey allowed active RDT screening for malaria among all household members with no clinical signs of malaria. The socio-environmental factors taken into account were: the area of residence (urban or peri-urban), domestic animals husbandry, water storage at home, nearby garbage dump, wastewater collection and disposal system, type of housing and number of people in the household. Results The frequency of asymptomatic malaria was 341 (38.8%) out of 879 household members visited. Both female and male gender was concerned (51% vs. 49%). The 5 to 25 years old group concentrated nearly 82% of all cases. Only domestic animals husbandry was associated with asymptomatic malaria at the household level (p = 0.021). Conclusions The high frequency of asymptomatic malaria found in this study is a challenge for the National Malaria Control Program in Côte d’Ivoire. This should be taken into account while organizing control strategies. Key messages The frequency of asymptomatic malaria in Côte d’Ivoire is high. Control strategies must take into account in the guidelines the challenges of detecting and treating asymptomatic malaria. For the judicious use of antimalarial drugs, any subject with a positive RDT without clinical signs of malaria should receive a ‘Drop - Thick’ before treatment.