Plasmodium malariae and Plasmodium ovale infections and their association with common red blood cell polymorphisms in a highly endemic area of Uganda

Abstract

Background: Plasmodium ovale and Plasmodium malariae infections are scarcely studied in sub-Saharan Africa, where the Plasmodium falciparum species predominates. The objective of this study is to investigate the prevalence of P. ovale and P. malariae infections and their relationship with common red blood cell polymorphisms in a cohort of 509 individuals from Uganda. Methods: Three cross-sectional surveys were conducted in individuals of 1-10 and >20 y of age from the Apac district at baseline and 6 and 16 weeks after drug treatment. Malaria infections were assessed by polymerase chain reaction and genotyping was performed for the sickle cell allele, α-thalassaemia and glucose-6-phosphate dehydrogenase. Results: At baseline, the prevalence of infection was 7.5%, 12.6% and 57.4% for P. ovale, P. malariae and P. falciparum species, respectively. Co-infections were present in 14.1% of individuals, all including P. falciparum parasites. In children 1-5 y of age, the prevalence of P. ovale mono-infections increased significantly from 1.7% to 7.3% over time (p=0.004) while the prevalence of P. malariae and P. falciparum infections declined significantly during this study. After adjusting for confounding and multiple testing, only α-thalassaemia had a statistically significant increase in the odds of P. falciparum infections (odds ratio 1.93 [95% confidence interval 1.26 to 2.94]). Conclusions: Common red blood cell polymorphisms do not show strong effects on mild Plasmodium infections in this Ugandan population. To understand the extent of this result, similar studies should be carried out in other populations using larger cohorts.

Prevalence and proportion of Plasmodium spp. triple mixed infections compared with double mixed infections: a systematic review and meta-analysis

“…Of the 35 studies, 14 (40%) were from the Asia-Pacific region, 9 (25.7%) were from Africa, 5 (14.3%) were from Europe, 4 (11.4%) were from Oceania, and three (8.6%) were from the (Table 1). Among 35 included studies from 22 different countries, most (4/35, 11.4%) were from Papua New Guinea [11][12][13][14], Cambodia [15][16][17], India [6,18,19], Italy [4,20,21], and Uganda [2,22,23]. Most of the participants included among the studies were residents (16/35, 45.7%), febrile patients (11/35, 31.4%), and malaria-positive cases (6/35, 17.1%).…”

First Observations of Plasmodium Malariae and Its Evolution During the Parasitological Evaluation of the Long-term Village Scale Malaria Vector Control Program in the Balombo Area of Angola

“…A great amount of work was devoted to Plasmodium malariae since its description by Grassi and Feletti in 1890 under the name Haemamoeba malariae in ancient [1][2][3][4][5][6][7][8][9][10], until recent studies [11][12][13][14][15][16]. Considered as benign, this Plasmodium species has been used in experimental infections for the treatment of neurosyphilis [10].…”