A Cross-Sectional Survey of Seroprevalence to P. Falciparum Antigens in Children Living Along the Border of Thailand and Myanmar and its Lack of Correlation with Nutritional Status and Anaemia.

Background: In Thailand, the prevalence of malaria was highest in the northern region and most infected cases were school-age children. This study aimed to determine the seroprevalence of antibodies against malaria antigens among school-age children living on the Thailand-Myanmar border and its correlation with nutritional status and anaemia. Methods: One-hundred and forty eight children in Tak Province were enrolled. Brief histories were taken, and dried blood spots collected on filter paper were used to determine antibodies to malaria antigens. Weight and height were measured, and body mass index (BMI) was calculated to assess health status. Results: The mean BMI was 16.2 kg/m2 (SD 2.6) and 116 (78%) children had normal BMI-for-age. The mean haematocrit was 38 % (SD 3) and 12 (9%) children had anaemia. Seroprevalence of antibodies to Plasmodium falciparum schizont extracts, the 19kDa of merozoite surface protein-1 and the apical membrane antigen-1 were 13.5%, 8.1% and 5.4%, respectively. The mean haematocrit and BMI-for-age were not statistically different between children with and without antibodies to malaria antigens. Conclusion: We report an overall rate of 17.6% of antibodies to malaria antigens in schoolage children living in an endemic area. No significant differences in nutritional status or anaemia were found between children who had and did not have the antibodies. The data from this study may contribute to understanding the relationship between health status and specific anti-P. falciparum antibody response in an area of low malaria transmission.