Sustained malaria control over an eight-year period in Papua New Guinea: the challenge of low-density asymptomatic infections
- Author(s)
- Koepfli, C; Ome-Kaius, M; Jally, S; Malau, E; Maripal, S; Ginny, J; Timinao, L; Kattenberg, JH; Obadia, T; White, M; Rarau, P; Senn, N; Barry, AE; Kazura, JW; Mueller, I; Robinson, LJ;
- Journal Title
- Journal of Infectious Diseases
- Publication Type
- Journal Article in press
- Abstract
- Background: The scale-up of effective malaria control in the last decade has resulted in a substantial decline in the incidence of clinical malaria in many countries. The effects on the proportions of asymptomatic and submicroscopic infections, and on transmission potential are yet poorly understood. Methods: In Papua New Guinea, vector control has been intensified since 2008, and improved diagnosis and treatment introduced in 2012. Cross-sectional surveys were conducted in Madang Province in 2006 (n=1280), 2010 (n=2117) and 2014 (n=2516). Infections were quantified by highly sensitive qPCR and gametocytes by RT-qPCR. Results: P. falciparum prevalence by qPCR decreased from 42% in 2006 to 9% in 2014. P. vivax prevalence decreased from 42% in 2006 to 13% in 2010, but then increased to 20% in 2014. Parasite densities decreased 5-fold from 2006 to 2010; 72% of P. falciparum and 87% of P. vivax infections were submicroscopic in 2014. Gametocyte density and positivity correlated closely with parasitemia, and population gametocyte prevalence decreased 3-fold for P. falciparum and 29% for P. vivax from 2010 to 2014. Conclusions: Sustained control has resulted in reduced transmission potential but an increasing proportion of gametocyte carriers are asymptomatic and submicroscopic and represent a challenge to malaria control.
- Publisher
- Oxford Academic
- Research Division(s)
- Population Health And Immunity
- PubMed ID
- 29029179
- Publisher's Version
- https://doi.org/10.1093/infdis/jix507
- Open Access at Publisher's Site
https://doi.org/10.1093/infdis/jix507- Terms of Use/Rights Notice
- Refer to copyright notice on published article.
Creation Date: 2017-10-16 02:00:04
Last Modified: 2017-10-17 08:07:48