Review of malaria situation in Cameroon: technical viewpoint on challenges and prospects for disease elimination

Abstract

Malaria still has a devastating impact on public health and welfare in Cameroon. Despite the increasing number of studies conducted on disease prevalence, transmission patterns or treatment, there are to date, not enough studies summarising findings from previous works in order to identify gaps in knowledge and areas of interest where further evidence is needed to drive malaria elimination efforts. The present study seeks to address these gaps by providing a review of studies conducted so far on malaria in Cameroon since the 1940s to date. Over 250 scientific publications were consulted for this purpose. Although there has been increased scale-up of vector control interventions which significantly reduced the morbidity and mortality to malaria across the country from a prevalence of 41% of the population reporting at least one malaria case episode in 2000 to a prevalence of 24% in 2017, the situation is not yet under control. There is a high variability in disease endemicity between epidemiological settings with prevalence of Plasmodium parasitaemia varying from 7 to 85% in children aged 6 months to 15 years after long-lasting insecticidal nets (LLINs) scale-up. Four species of Plasmodium have been recorded across the country: Plasmodium falciparum, P. malariae, P. ovale and P. vivax. Several primate-infecting Plasmodium spp. are also circulating in Cameroon. A decline of artemisinin-based combinations therapeutic efficacy from 97% in 2006 to 90% in 2016 have been reported. Several mutations in the P. falciparum chloroquine resistance (Pfcrt) and P. falciparum multidrug resistance 1 (Pfmdr1) genes conferring resistance to either 4-amino-quinoleine, mefloquine, halofanthrine and quinine have been documented. Mutations in the Pfdhfr and Pfdhps genes involved in sulfadoxine-pyrimethamine are also on the rise. No mutation associated with artemisinin resistance has been recorded. Sixteen anopheline species contribute to malaria parasite transmission with six recognized as major vectors: An. gambiae, An. coluzzii, An. arabiensis, An. funestus, An. nili and An. moucheti. Studies conducted so far, indicated rapid expansion of DDT, pyrethroid and carbamate resistance in An. gambiae, An. coluzzii, An. arabiensis and An. funestus threatening the performance of LLINs. This review highlights the complex situation of malaria in Cameroon and the need to urgently implement and reinforce integrated control strategies in different epidemiological settings, as part of the substantial efforts to consolidate gains and advance towards malaria elimination in the country.

Burden of moderate to severe anaemia and severe stunting in children ≤ 3 years in conflict hit Mount Cameroon: a community based descriptive cross-sectional study

“…The surveillance of moderate-to-severe anaemia (MdSA) is recommended for disease surveillance in countries with high prevalence of malaria and anaemia [7,15]. The prevalence of Plasmodium parasitaemia in children in Cameroon varies from 7 to 85% [16] hence, the need for constant 4 monitoring of the burden of MdSA and other nutrition related morbidities is invaluable.…”

Assessing Anopheles Vector Species Diversity and Transmission of Malaria in Cross-Border Areas of Côte d'Ivoire

“…Malaria transmission in Africa is very heterogeneous due to eco-climatic variations across the continent [4]. Currently, ve species of the Plasmodium genus have been identi ed as being responsible for malaria infection in humans [5,6].…”

Polyparasitism in School-Aged Children Living in the Schistosomiasis Endemic Focus of Muyuka-Cameroon after >8 Years of Sustained Control Measures: A Cross Sectional Study

“…With an estimated two million people with schistosomiasis in Cameroon and an additional ve million living in high transmission areas, annual MDA of praziquantel to SAC in endemic areas is the country's main control strategy against the disease [19,20]. Among the integrated malaria control strategies in different epidemiological settings in Cameroon, vector control intervention through distribution of long-lasting insecticidal nets (LLINs) has been scaled-up [21]. While the prevalence of these parasites have experienced a reduction due to mapping of schistosomiasis endemic areas and sustained MDA campaigns with praziquantel, PC with albendazole for STH and the scale-up of treated bed nets across the country between 2000 and 2015 for control of malaria [20,22,23], these have not been su cient in interrupting the transmission cycle of the parasites.…”