Prevalence of Plasmodium falciparum parasites with pfhrp2 exon 2 gene deletion in symptomatic malaria patients across Ghana in 2021.

backgroundPlasmodium falciparum histidine-rich protein 2-based rapid diagnostic tests (PfHRP2-based RDTs) are the most widely used malaria RDTs across Africa. The emergence and spread of pfhrp2 gene-deleted parasites have prompted nationwide surveillance to monitor trends and potential hotspots for P. falciparum with pfhrp2 gene deletions. This study evaluated the prevalence and distribution of P. falciparum with pfhrp2 gene deletions in Ghana in 2021.

methodsThis cross-sectional study utilized the First Response

resultsThe overall malaria positivity for the two RDTs was similar: 72.3% (95% CI: 71.4-73.2) for the First Response RDT and 71.5% (95% CI: 70.6-72.4) for the HRP2/panLDH Combo kit (p = 0.215). There were no pfhrp2 exon 2 gene deletions resulting from a false negative RDT, however, deletions were identified in 0.3% (19/5,611) of samples that tested positive for both the First Response RDT and the panLDH band of the Combo kit, and 9.1% (2/22) of the missed infections, leading to an overall pfhrp2 exon 2 gene deletion of 0.4% (21/5,633) in the population.

conclusionNo false negative sample was identified in this study, and less than 1% of parasites with pfhrp2 gene deletions (mainly from RDT positive samples) were found in the population . This finding offers assurance for the continued reliance on HRP2-based RDTs for malaria screening in public health clinics in Ghana. Nonetheless, continued surveillance is needed to determine the expansion of P. falciparum with these gene deletions.