In early 2014, dengue cases were reported from northern Mozambique, 30 years after the last outbreak. We identified potential dengue vector species in three northern towns, Pemba, Nampula and Nacala, and one southern town, Maputo, during the outbreak in April 2014. A major dengue vector species, Aedes (Stegomyia) aegypti, was found in all these towns. The dominant vector subspecies in the northern towns was Aedes aegypti aegypti, while Ae. aegypti formosus was dominant in Maputo. Considering the high proportion of Ae. aegypti aegypti and its high vector competence, the findings from this study suggest that Ae. aegypti aegypti was responsible for the outbreak in northern Mozambique.

Since malaria vaccine development is slow and parasite resistance to anti-malarial drugs is developing rapidly, vector control is still the most practical method for reducing malaria transmission in developing countries. House spraying and treated bed nets have been popular control measures targeting indoor resting mosquitoes; however, chemical insecticides should be treated and managed with great care. In this proposed study, we will evaluate the efficacy of bacterial larvicides combined with environmental management strategies for controlling malaria vectors and transmission in western Kenya. These control methods are less harmful to the environment. The article describes the study design and methods.

In early 2014, dengue cases werereported from the northern Mozambique, 30 years since the last outbreak. Weidentified potential dengue vector species in three northern towns, Pemba, Nampulaand Nacala, and one southern town, Maputo, during the outbreak in April 2014. Amajor dengue vector species, Aedes (Stegomyia) aegypti, wasfound in all these towns. The dominant vector subspecies in the northern townswas Aedes aegypti aegypti, while Ae. aegyptiformosus was dominant in Maputo. Considering the high proportions of Ae. aegypti aegypti and its high vectorcompetence, the findings from this study suggest that Ae. aegypti aegypti was responsible for the outbreakin the northern Mozambique.

A prospective case–control study was conducted in urban districts in Hanoi, northern Vietnam to evaluate the effect of migration on the risk of hospitalisation for dengue in a Vietnamese urban population. We enrolled laboratory-confirmed dengue patients aged >18 years who were hospitalised in local hospitals in November and December 2010. Four neighbourhood-matched controls for each case were recruited within a week of hospitalisation. Sociodemographic data were collected by interviews, and the number of immature and adult mosquitoes within household premises was counted by entomological survey. Matched-pair analyses were conducted using conditional logistic regression models. Among 43 cases and 168 controls, 84% and 83% were migrants from rural areas, respectively. Although statistical significance was marginal, recent migration (residing in study area for <5 years) independently increased the risk of hospitalisation for dengue compared with inhabitants after controlling for potential confounders (adjusted odds ratio [aOR] = 3.78; 95% confidence interval [CI] = 0.99–14.27), whereas longer-term migration (residing in study area for >6 years) did not change the risk (aOR = 1.1; 95% CI = 0.30–4.05). Younger age (18–34 years) (aOR = 7.26; 95% CI = 2.39–22.06) and higher adult Aedes aegypti infestation level within household premises (aOR = 9.25; 95% CI = 1.68–51.09) were also independently associated with hospitalisation for dengue. Recent migration from rural areas seems to increase the risk of hospitalisation for dengue in urban populations in endemic areas. Further research including cohort study should be done to confirm the impact of migration on the risk of dengue in urban areas.