High prevalence and risk of malaria among asymptomatic individuals from villages with high prevalence of artemisinin partial resistance in Kyerwa district of Kagera region, north-western Tanzania

• Published in: Malaria journal Vol. 23; no. 1; pp. 197 - 18
• Main Authors: Mandai, Salehe S, Francis, Filbert, Challe, Daniel P, Seth, Misago D, Madebe, Rashid A, Petro, Daniel A, Budodo, Rule, Kisambale, Angelina J, Chacha, Gervas A, Moshi, Ramadhan, Mbwambo, Ruth B, Pereus, Dativa, Bakari, Catherine, Aaron, Sijenunu, Mbwambo, Daniel, Lusasi, Abdallah, Kajange, Stella, Lazaro, Samuel, Kapologwe, Ntuli, Mandara, Celine I, Ishengoma, Deus S
• Format: Journal Article
• Language: English
• Published: England BioMed Central Ltd 26-06-2024; BioMed Central; BMC
• Subjects: Adolescent; Adult; Aged; Antimalarials - pharmacology; Antimalarials - therapeutic use; Artemisinin partial resistance; Artemisinins - pharmacology; Artemisinins - therapeutic use; Asymptomatic infections; Child; Child, Preschool; Cross-Sectional Studies; Disease transmission; Drug Resistance; Elementary school students; Female; Health aspects; Humans; Infant; Infection; Kelch 13; Malaria; Malaria - epidemiology; Malaria, Falciparum - epidemiology; Malaria, Falciparum - parasitology; Male; Medical research; Medicine, Experimental; Middle Aged; Plasmodium falciparum; Plasmodium falciparum - drug effects; Predictors/risk factors of malaria infections; Prevalence; Prevalence studies (Epidemiology); Pyrimethamine; Risk Factors; Statistics; Tanzania - epidemiology; Young Adult; Tanzania; Kelch 13; Plasmodium falciparum; Artemisinin partial resistance; Predictors/risk factors of malaria infections; Asymptomatic infections; Malaria; Tanzania
• ISSN: 1475-2875; 1475-2875
• DOI: 10.1186/s12936-024-05019-5

Although Tanzania adopted and has been implementing effective interventions to control and eventually eliminate malaria, the disease is still a leading public health problem, and the country experiences heterogeneous transmission. Recent studies reported the emergence of parasites with artemisinin partial resistance (ART-R) in Kagera region with high prevalence (> 10.0%) in two districts of Karagwe and Kyerwa. This study assessed the prevalence and predictors/risk of malaria infections among asymptomatic individuals living in a hyperendemic area where ART-R has emerged in Kyerwa District of Kagera region, north-western Tanzania.
This was a community-based cross-sectional survey which was conducted in July and August 2023 and involved individuals aged ≥ 6 months from five villages in Kyerwa district. Demographic, anthropometric, clinical, parasitological, type of house inhabited and socio-economic status (SES) data were collected using electronic capture tools run on Open Data Kit (ODK) software. Predictors/risks of malaria infections were determined by univariate and multivariate logistic regression, and the results were presented as crude (cORs) and adjusted odds ratios (aORs), with 95% confidence intervals (CIs).
Overall, 4454 individuals were tested using rapid diagnostic tests (RDTs), and 1979 (44.4%) had positive results. The prevalence of malaria infections ranged from 14.4% to 68.5% and varied significantly among the villages (p < 0.001). The prevalence and odds of infections were significantly higher in males (aOR = 1.28, 95% CI 1.08 -1.51, p = 0.003), school children (aged 5-≤10 years (aOR = 3.88, 95% CI 3.07-4.91, p < 0.001) and 10-≤15 years (aOR = 4.06, 95% CI 3.22-5.13, p < 0.001)) and among individuals who were not using bed nets (aOR = 1.22, 95% CI 1.03-1.46, p = 0.024). The odds of malaria infections were also higher in individuals with lower SES (aOR = 1.42, 95% CI 1.17-1.72, p < 0.001), and living in houses without windows (aOR = 2.08, 95% CI 1.46-2.96, p < 0.001), partially open (aOR = 1.33, 95% CI 1.11-1.58, p = 0.002) or fully open windows (aOR = 1.30, 95%CI 1.05-1.61, p = 0.015).
The five villages had a high prevalence of malaria infections and heterogeneity at micro-geographic levels. Groups with higher odds of malaria infections included school children, males, and individuals with low SES, living in poorly constructed houses or non-bed net users. These are important baseline data from an area with high prevalence of parasites with ART-R and will be useful in planning interventions for these groups, and in future studies to monitor the trends and potential spread of such parasites, and in designing a response to ART-R.