Plasmodium malariae contributes to high levels of malaria transmission in a forest-savannah transition area in Cameroon.

BACKGROUND: Malaria control efforts are highly skewed towards Plasmodium falciparum while overlooking other Plasmodium species such as P. malariae. A better understanding of the role of Plasmodium species other than P. falciparum is needed to strengthen malaria elimination initiatives. The aim of the present study was to elucidate the contribution of P. malariae to malaria transmission in Cameroon. METHODS: The study was conducted in the Ngatti Health District, a forest-savannah transition area in the Adamawa Region, Cameroon. A total of 497 individuals aged from 1 to 85 years were diagnosed with malaria in November 2020 using a rapid diagnostic test (RDT) and microscopy. Adult mosquitoes were collected between September 2019 and March 2020 by indoor aspiration and identified morphologically and molecularly. The infection status of Plasmodium spp. was also determined by quantitative PCR, and dried blood spots were collected from 156 participants with the aim to detect different Plasmodium species by nested PCR. RESULTS: The overall Plasmodium prevalence was 50.3%, 51.8% and 64.7%, as detected by microscopy, the RDT and PCR, respectively. Based on the PCR results, P. falciparum was the most prevalent species (43%); followed by co-infections P. falciparum/P. malariae (17%), P. falciparum/P. ovale (1.3%), P. falciparum/P. ovale/P. malariae (1.3%); and then by P. malariae mono-infection (2.5%). The same trend was observed using microscopy, with 35% of participants infected with P. falciparum, 11% co-infected with P. falciparum/P. malariae and 4% infected with P. malariae. The prevalence and parasite density of malaria infection varied significantly with age group (P < 0.05), with the highest prevalence rate observed in children aged 6-10 years (P = 0.0001) while the density of Plasmodium infection increased significantly in children aged < 5 years compared to the other age groups (P = 10-3). Among the 757 Anopheles mosquitoes collected, 737 (97.35%) were An. funestus sensu stricto, 15 (1.9%) were An. gambiae and 5 (0.6%) were An. hancocki. The Plasmodium species recorded at the head/thorax level were P. falciparum and P. malariae, with a sporozoite infection rate of 8.4%; the highest sporozoite infection rate was recorded at Mibellon village (13.6%). CONCLUSION: The results of this study reveal the significant contribution of P. malariae, in addition to P. falciparum, to the high malaria transmission rate in this region. These findings highlight the need to deploy initiatives to also tackle this Plasmodium species to eliminate malaria in the region.

Knowledge and practices toward COVID-19 preventive measures and symptoms: A case-control study in Benin

Introduction. Following communication and awareness actions related to COVID-19, we assessed the knowledge and practices about COVID-19 in Benin. Methods. A case-control survey was conducted from 14 September to 20 October 2020 in Benin. Questions relatingto knowledge and practices on COVID-19 were collected through a questionnaire survey. A total of 312 respondents (104 cases and 208 controls) were included in the study. Logistic regression and Spearman correlation tests were used to examine the relation between participants knowledge and practice at a 5% significance level. Results. From the survey, 65.4% of cases and 68.3% of controls knew about COVID-19 transmission via air droplets. Most of the cases (67.31%) and control (79.81%) participants reported cough as a symptom of COVID-19. Handwashing with soap and water was the most protective measure known by 87.5% of cases and 90.87% of controls. Concerning practice, the cloth mask was the type mostly worn by cases (54.81%) and controls (58.65%). Wearing a face mask in public areas was significantly associated with the COVID-19 health status of respondents (OR = 2.98, CI95% [1.16-7.67]; p = 0.022). Furthermore, a significantly positive correlation exists between knowledge of the COVID-19 protective measures and hand hygiene practices when leaving a public place (r = 0.184, p=0.001). Conclusion. Through this study, we observed some discrepancies between the knowledge and practices related to COVID-19 among cases and controls surveyed. Therefore, efforts should be directed toward raising awareness about the disease to improve their knowledge and practices