Background Malaria is a vector-borne parasitic disease that continues to be a global public health threat. Five different species of the genus Plasmodium (P. falciparum, P. malariae, P. ovale curtisi, P. ovale wallikeri, and P. vivax) cause malaria in Sub-Saharan Africa. Previous cross-sectional surveys from 2013 and 2017 indicated the circulation of P. vivax in the West region of Cameroon, prompting an investigation into the prevalence of all non-falciparum malaria parasite species in this region.

Methods A cross-sectional facility-based study recruited 431 clinically suspected cases of malaria from three health centres in the West region of Cameroon in 2020. Socio-demographic, clinical data, and dried blood spots (DBS) were collected from all consenting patients. Parasite DNA was extracted from DBS for real-time PCR amplification of species-specific Plasmodium 18S rRNA for P. falciparum, P. ovale, P. malariae, and P. vivax. In addition, P. ovale was further sub-classified into P. ovale curtisi or P. ovale wallikeri. The prevalence of different species was measured.

Results Among the 431 samples, the overall malaria prevalence was 54.8% (236/431). Of these, 49.9% were infected with P. falciparum, 4% with P. ovale, and 0.9% with P. malariae. No P. vivax was detected. Mixed infections were common, with 3.5% of the infections harbouring more than one Plasmodium species. A total of 5 P. ovale and 1 P. malariae mono-infections were detected. Of the 17 P. ovale infections, 12 were successfully genotyped, with 6 P. ovale curtisi, 3 P. ovale wallikeri, and 3 mixture of the species.

Conclusions While falciparum remains the dominant malaria parasite species among acute febrile illness cases, non-falciparum malaria is also commonly found in Dschang, both as a co-infection with P. falciparum and as mono-infections. Both subspecies of P. ovale are present in the region. Continued monitoring of non-falciparum species is needed for understanding malaria burden in West Cameroon.

JBP reports research funding from Gilead Sciences and non-financial support from Abbott Laboratories, both outside the scope of this manuscript. All other authors declare no competing interest.

This work was supported by the National Institute of Allergy and Infectious Diseases, National Institutes of Health (R21AI152260 to J. T. L., K24AI134990 to J.J.J, R01AI165537 to J.J.J and R.R.D, U19AI181584 to R.R.D.), and in part by EDCTP2-TMA2020CDF-31771 to IMA).

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The details of the IRB/oversight body that provided approval or exemption for the research described are given below:

Ethics committee/IRB of Cameroon Baptist Convention Health Board (FWA00002077) gave ethical approval for this work.

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