Detecting temporal and spatial malaria patterns from first antenatal care visits

Pregnant women attending first antenatal care (ANC) visits represent a promising malaria surveillance target in Sub-Saharan Africa. We assessed the spatio-temporal relationship between malaria trends at ANC (n = 6471) and in children in the community (n = 3933) and at health facilities (n = 15,467) in southern Mozambique (2016-2019). ANC P. falciparum rates detected by quantitative polymerase chain reaction mirrored rates in children, regardless of gravidity and HIV status (Pearson correlation coefficient [PCC] > 0.8, & chi;(2)<1.1), with a 2-3 months lag. Only at rapid diagnostic test detection limits at moderate-to-high transmission, did multigravidae show lower rates than children (PCC = 0.61, 95%CI[-0.12-0.94]). Seroprevalence against the pregnancy-specific antigen VAR2CSA reflected declining malaria trends (PCC = 0.74, 95%CI[0.24-0.77]). 60% (9/15) of hotspots detected from health facility data (n = 6662) using a novel hotspot detector, EpiFRIenDs, were also identified with ANC data (n = 3616). Taken together, we show that ANC-based malaria surveillance offers contemporary information on temporal trends and geographic distribution of malaria burden in the community. Pregnant people visiting antenatal clinics may represent a useful sentinel surveillance population for monitoring infections such as malaria. Here, the authors investigate the potential of this approach by comparing malaria prevalence in pregnant people and children living in the same area of southern Mozambique.

Automated summary

The study found a spatio-temporal relationship between malaria trends in pregnant women attending first antenatal care visits and in children and health facilities. The P. falciparum rates detected in antenatal care mirrored rates in children, with a 2-3 months lag. The seroprevalence of pregnancy-specific antigen VAR2CSA reflected declining malaria trends. ANC-based malaria surveillance offers valuable information on temporal trends and geographic distribution of malaria burden.