Malaria infection and undernutrition frequently coexist in malaria endemic regions where pregnant women and children under the age of five bear the greatest burden. Nutrition is known to modulate malaria morbidity and mortality; however, the interaction between suboptimal nutrition and malaria immunity remains poorly understood.
We investigated the influence of a maternal lipid based nutrient supplementation on acquisition of antibodies to malaria during pregnancy and association with pregnancy outcomes. Naturally acquired antibody levels were measured against pregnancy-specific and non-pregnancy-specific P.falciparum variant surface antigens (VSA) and merozoite antigens (MSP-1, MSP-2, MSP-3, Rh2A9 and EBA-175, recognized as potential vaccine candidates) at <20 and 36 gestation weeks (gw), in a cohort of pregnant women currently enrolled in a nutrient supplementation trial in Malawi, Africa.
Preliminary results show that total immunoglobulin G (IgG) and functional antibodies to pregnancy-specific VSA significantly increased during pregnancy (p<0.0001), and were positively correlated with maternal haemoglobin levels (p=0.0071), suggesting a role in protection against malaria-induced anaemia. Antibodies to merozoite antigens and non-pregnancy-specific VSA however declined or fluctuated, possibly due to the lack of exposure to malaria over pregnancy, and were not associated with pregnancy outcomes. Antibody levels were not associated with birth weight or were affected by the use of insecticide treated bed nets. HIV infection (13% prevalence) was associated with lower levels of antibodies to MSP-2, pregnancy and non-pregnancy-specific VSA agreeing with previous findings.
Further research is currently underway investigating the association between the type of nutrient supplementation and malaria antibody levels in pregnant women and their infants. If nutrient supplementations are found to have a positive effect on malaria immunity and fetal and infant growth, they could be an important complement to conventional malaria prevention as a cost effective method of improving clinical outcomes in vulnerable groups.