Insecticide-treated nets and malaria prevalence, Papua New Guinea, 2008-2014

• Published in: Bulletin of the World Health Organization Vol. 95; no. 10; pp. 695 - 705B
• Main Authors: Hetzel, Manuel W, Pulford, Justin, Ura, Yangta, Jamea-Maiasa, Sharon, Tandrapah, Anthony, Tarongka, Nandao, Lorry, Lina, Robinson, Leanne J, Lilley, Ken, Makita, Leo, Siba, Peter M, Mueller, Ivo
• Format: Journal Article
• Language: English
• Published: Switzerland World Health Organization 01.10.2017
• Subjects: Altitude; Anemia; Anopheles; Artemisinin; Blood tests; Case management; Child; Child, Preschool; Combination therapy; Confidence intervals; Culicidae; Disease transmission; Epidemics; Fever; Health care management; Highland areas; Households; Humans; Infant; Infections; Insecticide-Treated Bednets - statistics & numerical data; Insecticides; Insecticides - pharmacology; Light microscopy; Malaria; Malaria - epidemiology; Malaria - parasitology; Malaria - prevention & control; Medical research; Microscopy; Morbidity; Mosquito Control - methods; Mosquitoes; Nets; Papua New Guinea - epidemiology; Parasitemia - epidemiology; Parasitemia - parasitology; Parasitemia - prevention & control; Pesticides; Plasmodium - drug effects; Plasmodium falciparum; Plasmodium vivax; Polls & surveys; Prevalence; Primary Prevention - methods; Prone; Splenomegaly; Towns; Trust; Vector-borne diseases; Villages; Papua New Guinea
• ISSN: 0042-9686; 1564-0604
• DOI: 10.2471/BLT.16.189902

To investigate changes in malaria prevalence in Papua New Guinea after the distribution of long-lasting Insecticide-treated nets, starting in 2004, and the introduction of artemisinin-based combination therapy in 2011. Two malaria surveys were conducted in 2010-2011 and 2013-2014. They included 77 and 92 randomly selected villages, respectively. In each village, all members of 30 randomly selected households gave blood samples and were assessed for malaria infection by light microscopy. In addition, data were obtained from a malaria survey performed in 2008-2009. The prevalence of malaria below 1600 m in altitude decreased from 11.1% (95% confidence interval, CI: 8.5-14.3) in 2008-2009 to 5.1% (95% CI 3.6-7.4) in 2010-2011 and 0.9% (95% CI 0.6-1.5) in 2013-2014. Prevalence decreased with altitude. was more common than overall, but not everywhere, and initially the prevalence of infection decreased more slowly than infection. Malaria infections were clustered in households. In contrast to findings in 2008-2009, no significant association between net use and prevalence was found in the later two surveys. The prevalence of both fever and splenomegaly also decreased but their association with malaria infection became stronger. Large-scale insecticide-treated net distribution was associated with an unprecedented decline in malaria prevalence throughout Papua New Guinea, including epidemic-prone highland areas. The decline was accompanied by broader health benefits, such as decreased morbidity. Better clinical management of nonmalarial fever and research into residual malaria transmission are required.