Increased investment in gametocytes in asymptomatic Plasmodium falciparum infections in the wet season.

摘要: Transmission stemming from asymptomatic infections is increasingly being recognized as a threat to malaria elimination. In many regions, transmission seasonal. It not well understood whether Plasmodium falciparum modulates its investment in coincide with seasonal vector abundance. We sampled 1116 individuals the wet season, when vectors are abundant, and 1743 dry two sites western Kenya, representing different intensities (Chulaimbo, moderate transmission, Homa Bay, low transmission). Blood samples were screened for P. by qPCR, gametocytes pfs25 RT-qPCR. Parasite prevalence qPCR was 27.1% dry), 48.2% wet), 9.4% (Homabay, 7.8% wet). Mean parasite densities did differ between seasons (P = 0.562). transcripts detected 119/456 (26.1%) of infections. fewer harbored detectable (22.3% vs. 33.8%, P = 0.009), but 3-fold higher (wet: 3.46 transcripts/uL, dry: 1.05 P   1 gametocyte per 2 uL blood), compared 7.9% season. Children aged 5–15 years 76.7% at moderate-to-high densities. Parasites increase their reflected Despite increased densities, density remained similar across often below limit detection microscopy or rapid diagnostic test, thus large proportion infective would escape population screening Seasonal changes gametocytemia need be considered designing control measures.