AUTHOR=Kosasih Ayleen , Utami Retno Ayu Setya , Noviyanti Rintis , Elyazar Iqbal R. F. , Lestari Karina Dian , Raimanus Valentinus Seran , Longley Rhea J. , Baird J. Kevin , Robinson Leanne J. , Sutanto Inge , Mueller Ivo TITLE=Agreement between serological data on schoolchildren and the number of malaria cases in the remaining high-burden villages of Indonesia JOURNAL=Frontiers in Malaria VOLUME=2 YEAR=2024 URL=https://www.frontiersin.org/journals/malaria/articles/10.3389/fmala.2024.1362585 DOI=10.3389/fmala.2024.1362585 ISSN=2813-7396 ABSTRACT=Introduction

In areas where malaria transmission has been successfully reduced, surveillance based solely on clinical cases becomes increasingly challenging. Antibodies generated by the host in response to malaria infections may persist in the circulation for several months or longer. We assessed a serological surveillance tool to measure malaria transmission in eastern Indonesia where reported cases have been recently declining.

Methods

In June 2021, we conducted a cross-sectional survey of elementary schoolchildren aged 5 to 14 years residing in six villages in an endemic area of West Timor, Indonesia. Annual Parasite Incidence (API, cases/1,000 residents/year) of these villages ranged from 0.0 to 4.1 in 2021. Finger-prick plasma samples were tested using a multiplexed Luminex MAGPIX® bead array system to measure IgG antibodies against a panel of 8 Plasmodium vivax antigens. Using a random forest classification algorithm, individuals with predicted exposure to P. vivax in the prior 9 months were identified.

Results

15 of 398 (4%) schoolchildren were seropositive for recent P. vivax exposure. Remarkably, 87% (13/15) of seropositive children were from one village, the one with the highest API (4.1). In contrast, one seropositive child was from a village with an API of 1.3, and another from a village with an API of 0.0.

Conclusion

Our serological survey data confirms the reported malaria cases from PHC in the villages with likely ongoing transmission. Malaria programs may consider Lamea as the target for intervention.