There are over 500 species of the genus Artemisia in the Asteraceae family distributed over the globe, with varying potentials to treat different ailments. Following the isolation of artemisinin (a potent anti-malarial compound with a sesquiterpene backbone) from Artemisia annua, the phytochemical composition of this species has been of interest over recent decades. Additionally, the number of phytochemical investigations of other species, including those of Artemisia afra in a search for new molecules with pharmacological potentials, has increased in recent years. This has led to the isolation of several compounds from both species, including a majority of monoterpenes, sesquiterpenes, and polyphenols with varying pharmacological activities. This review aims to discuss the most important compounds present in both plant species with anti-malarial properties, anti-inflammatory potentials, and immunomodulating properties, with an emphasis on their pharmacokinetics and pharmacodynamics properties. Additionally, the toxicity of both plants and their anti-malaria properties, including those of other species in the genus Artemisia, is discussed. As such, data were collected via a thorough literature search in web databases, such as ResearchGate, ScienceDirect, Google scholar, PubMed, Phytochemical and Ethnobotanical databases, up to 2022. A distinction was made between compounds involved in a direct anti-plasmodial activity and those expressing anti-inflammatory and immunomodulating activities or anti-fever properties. For pharmacokinetics activities, a distinction was made between compounds influencing bioavailability (CYP effect or P-Glycoprotein effect) and those affecting the stability of pharmacodynamic active components.

In Cameroon, like in other African countries, infusions of Artemisia afra and Artemisia annua are widely used for the management of health-related problems, including malaria. The secondary metabolite contents of medicinal plants vary between different geographical regions and seasons, directly influencing their effectiveness in treating ailments. This study explores the phytochemical diversity and anti-plasmodial potential of A. annua and A. afra from distinct geographical locations within Cameroon, aiming to define the optimal chemical composition in terms of anti-plasmodial activity. Extracts were prepared from plants collected from diverse regions in Cameroon during both the rainy and dry seasons, and their metabolic contents were analyzed using Thin-Layer Chromatography (TLC), High Performance Liquid Chromatography (HPLC), and Gas Chromatography (GC). Their anti-plasmodial potential was assessed on a chloroquine-sensitive 3D7 Plasmodium falciparum strain. Additionally, the environmental parameters of the collecting sites were retrieved from multispectral satellite imagery. The activity profiles of the samples were associated with their environment, with distinct phytochemical compositions observed for each sample based on its geographical origin and season. Traces of artemisinin were detected in some of the A. afra samples, but it was present in the A. annua samples at a significantly higher concentration, especially in the rainy season samples (highest concentration in the Adamawa region, at 8.9% m/m artemisinin in the dry extract). Both plants are active at different levels, with A. annua more active due to the presence of artemisinin and A. afra probably active due to the presence of polyphenols. Both season and geographical location influence both plants’ metabolic contents and hence their antimalaria activity. These findings suggest that the selection of a suitable Artemisia sample for use as a potential antimalarial treatment should take into consideration its geographical origin and the period of collection.

Malaria is the most widespread endemic disease in Cameroon, and asymptomatic Plasmodium (gametocyte) carriers (APCs) constitute more than 95% of infectious human reservoirs in malaria endemic settings. This study assesses the knowledge of asymptomatic malaria (ASM) among health care workers (HCWs) in health facilities (HFs) in the Centre Region of Cameroon and the acceptability of using Artemisia afra tea to treat APCs. A cross-sectional descriptive survey was conducted among 100 HCWs, in four randomly selected HFs in the Centre Region, in the period of 1–20 April 2022, using semi-structured self-administered questionnaires. Logistic regression analyses were performed to determine factors associated with knowledge. More than seven in eight (88%) respondents were aware of the existence of ASM, 83% defined ASM correctly, 75% knew how it was diagnosed, 70% prescribe ACTs for APCs, and 51.1% were informed about ASM transmission. The professional category of HCWs was significantly associated with their knowledge of the existence and transmission of ASM, and longevity of service was associated with knowledge of transmission (p < 0.05). Two-thirds (67%) of respondents knew about Artemisia afra tea, 53.7% believed that it was effective in treating ASM, and 79% were willing to prescribe it if authorized. There was a fair level of knowledge of ASM among HCWs in the study settings.

Croton sylvaticus, a tropical African plant, is traditionally used to treat several diseases, including fever, inflammation, and malaria. Essential oils (EOs) from the plant’s leaves, roots, and trunk bark were obtained by hydrodistillation, and their chemical composition was analyzed by gas chromatography–mass spectrometry (GC-MS). The major constituents identified were virdiflorene (18.13 ± 0.46%) in root EO, (E)-β-caryophyllene (18.40 ± 0.60%) in trunk bark EO, and farnesyl acetone (15.26 ± 0.25%) in leaf EO. Notably, Cameroonian C. sylvaticus leaf EO exhibited a distinct and newly described chemotype with high levels of farnesyl acetone, β-copaene-4-α-ol, β-cadinene, α-humulene, and trans-longipinocarveol. In vitro testing revealed significant antiplasmodial activity against Plasmodium falciparum asexual (Pf3D7) and sexual (NF-54 strain) stages, with trunk bark EO showing the highest potency (IC₅₀: 9.06 ± 2.15 µg/mL for Pf3D7 and 0.56 µg/mL for gametocytes). These findings support the traditional antimalarial use of C. sylvaticus and represent the first chemical profile and antiplasmodial efficacy report for its root and trunk bark EOs against both parasite stages. To the best of our knowledge, we also report for the first time the antiplasmodial activity of an EO that exerts significant activity against both the asexual and sexual forms of P. falciparum.

Malaria is a major public health challenge in low- and middle-income countries with significant socio-economic impacts. While chemotherapy has greatly contributed to malaria control, the widespread emergence of resistance to antimalarial drugs threatens progress towards elimination goals. In parallel, the recent rollout of the RTS,S/AS01 and R21/Matrix-M malaria vaccine—targeting the Plasmodium falciparum circumsporozoite protein (CSP)—offers a new prevention tool but may be influenced by parasite genetic diversity. This study investigated the genetic architecture of Plasmodium falciparum circulating in a community in the Southwest Region of Cameroon. Seventy-two blood samples were analyzed using targeted Oxford Nanopore sequencing of pfcrt, pfmdr1, pfdhfr, pfdhps, pfkelch13 and pfcsp genes. We observed a high prevalence of pfdhfr mutations (98.6% N51I, 98.6% C59R, 97.7% S108N) and pfmdr1 Y184F (76.1%) mutation. Mutations in pfdhps (54.2% S436A, 2.8% A437G, 38.9% A581G) were also observed. No WHO-validated pfkelch13 artemisinin resistance markers were found; however, K189T (63.4%) and R255K (4.2%) variants were detected. Nineteen non-synonymous SNPs were identified in pfcsp, reflecting natural background variations as vaccination status was not known. These findings support the continued use of artemisinin-based combination therapies and underscores the need for sustained molecular surveillance of both antimalarial drug resistance and vaccine-related polymorphisms, to inform malaria control strategies.