Prevalence of non-falciparum malaria infections among asymptomatic individuals in four regions of Mainland Tanzania

Parasit Vectors. 2024 Mar 23;17(1):153. doi: 10.1186/s13071-024-06242-4.

Abstract

Background: Recent studies point to the need to incorporate the detection of non-falciparum species into malaria surveillance activities in sub-Saharan Africa, where 95% of the world's malaria cases occur. Although malaria caused by infection with Plasmodium falciparum is typically more severe than malaria caused by the non-falciparum Plasmodium species P. malariae, P. ovale spp. and P. vivax, the latter may be more challenging to diagnose, treat, control and ultimately eliminate. The prevalence of non-falciparum species throughout sub-Saharan Africa is poorly defined. Tanzania has geographical heterogeneity in transmission levels but an overall high malaria burden.

Methods: To estimate the prevalence of malaria species in Mainland Tanzania, we randomly selected 1428 samples from 6005 asymptomatic isolates collected in previous cross-sectional community surveys across four regions and analyzed these by quantitative PCR to detect and identify the Plasmodium species.

Results: Plasmodium falciparum was the most prevalent species in all samples, with P. malariae and P. ovale spp. detected at a lower prevalence (< 5%) in all four regions; P. vivax was not detected in any sample.

Conclusions: The results of this study indicate that malaria elimination efforts in Tanzania will need to account for and enhance surveillance of these non-falciparum species.

Keywords: Plasmodium malariae; Plasmodium ovale; Plasmodium vivax; Asymptomatic malaria; Malaria; Non-falciparum species; Tanzania.

MeSH terms

  • Asymptomatic Infections / epidemiology
  • Cross-Sectional Studies
  • Humans
  • Malaria* / epidemiology
  • Malaria, Falciparum* / epidemiology
  • Malaria, Vivax* / epidemiology
  • Plasmodium falciparum
  • Plasmodium malariae
  • Prevalence
  • Tanzania / epidemiology