Malária incubada: a mixed methods analysis on knowledge and experiences on Plasmodium vivax and asymptomatic malaria infections in a hard-to-reach and mobile population in the Amazon.

Background: As the Americas move towards malaria elimination, its circulation is increasingly concentrated in isolated communities with poor access to healthcare, and the silent human reservoir is a challenge (particularly for Plasmodium vivax). The deployment of tafenoquine for radical treatment is an important new asset. The CUREMA project evaluates a complex intervention aiming at malaria elimination in artisanal and small-scale gold mining (ASGM) communities of the Guiana Shield Region. A pre-intervention assessment was conducted to explore ASGM populations' knowledge and perceptions of asymptomatic Plasmodium carriage and P. vivax malaria.

Methods: The target population was the ASGM community working across Suriname, French Guiana and Amapá (Brazil). Data was collected in 2022 in ASGM cross-border staging areas, during the CUREMA pre-intervention qualitative and quantitative (cross-sectional) surveys. This analysis explores knowledge, experiences and representations on asymptomatic plasmodial carriage, recurrences and P. vivax infections.

Results: The qualitative survey included 25 semi-structured interviews, 14 group interviews and 38 informal conversations. The quantitative survey included 539 participants, mostly men (73.5%), with a median age of 38 years. Almost all the participants recognized mosquitoes as vectors of malaria, and a fraction recognized a microorganism as the causative agent of the disease. Awareness of asymptomatic forms of the disease ("malária incubada") and of risk of recurrences was common, and they were generally considered to be the result of inadequate treatment. Most participants could identify different types of malaria, but knowledge about P. vivax characteristics and radical treatment was limited.

Conclusions: Understanding the interpretation of the disease by affected communities is essential to develop context-specific strategies and for enhancing acceptability and effectiveness of malaria elimination efforts. Trial registration NCT05540470 on clinical trials.