microscopic plasmodium falciparum gametocytemia and infectivity to mosquitoes in cambodia

• DOI: 10.17615/cb2v-gq18
• Publication Date: 2015-12-13
• Authors: Sujata Balasubram...; Thay Kheang Heng; Panita Gosi; Piyaporn Saingam; Ratawan Ubalee; Lauren Levitz; Nitima Chanarat; Charlotte A. Lanteri; Sarath Nuom; Chanudom Ponsa; Dav Vy; Christian M. Parobek; Jessica T. Lin; Sok Somethy; Savoeun San; Worachet Kuntawun...; David L. Saunders; Chanthap Lon; Rifat Rahman; Hana Burkly; Char Meng Chuor; Michele D. Spring; Steven R. Meshnick
• Keywords: Adult; Adolescent; Plasmodium falciparum; Middle Aged; Parasitemia; Parasite Load; Insect Vectors; 3. Good health; Young Adult; 03 medical and health sciences; 0302 clinical medicine; Anopheles; Animals; Humans; Female; Malaria, Falciparum; Aged

Although gametocytes are essential for malaria transmission, in Africa many falciparum-infected persons without smear-detectable gametocytes still infect mosquitoes. To see whether the same is true in Southeast Asia, we determined the infectiousness of 119 falciparum-infected Cambodian adults to Anopheles dirus mosquitoes by membrane feeding. Just 5.9% of subjects infected mosquitoes. The 8.4% of patients with smear-detectable gametocytes were >20 times more likely to infect mosquitoes than those without and were the source of 96% of all mosquito infections. In low-transmission settings, targeting transmission-blocking interventions to those with microscopic gametocytemia may have an outsized effect on malaria control and elimination.