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Aedes aegypti female mosquitoes are the principal transmitters of dengue and other vector-borne infections. This species is closely associated with human habitation, due to its blood-feeding habits and the presence of breeding sites widely available around households. In this paper, we introduce a mathematical model for the life cycle of Aedes aegypti mosquitoes comprising two stages, aerial and aquatic, that reflects seasonal changes in the mosquito abundance. This model is further amended by three season-dependent control actions. Two coercive actions are introduced during the hot seasons characterized by higher abundance and enhanced growth rates of mosquitoes. They consist in the application of two chemical substances, insecticide and larvicide, acting upon the aerial and aquatic mosquito stages, respectively. During the cool seasons, characterized by the slower growth rates of mosquitoes and abundance of quiescent unhatched eggs, we introduce a preventive vector control measure consisting in mechanical elimination of mosquito breeding sites. Using the framework of optimal control in combination with the cost-benefit approach and epidemiological assessment, we identify the most efficient strategy capable of essentially reducing the population of adult and immature mosquitoes during both seasons and provide a sketch for its modus operandi.

Industrial activities have produced profound changes in the natural environment, including the mass removal of trees, fragmentation of habitats, and creation of larval mosquito breeding sites, that have allowed the vectors of disease pathogens to thrive. We conducted a review of the literature to assess the impact of industrial activities on vector-borne disease transmission. Our study shows that industrial activities may be coupled with significant changes to human demographics that can potentially increase contact between pathogens, vectors and hosts, and produce a shift of parasites and susceptible populations between low and high disease endemic areas. Indeed, where vector-borne diseases and industrial activities intersect, large numbers of potentially immunologically naïve people may be exposed to infection and lack the knowledge and means to protect themselves from infection. Such areas are typically associated with inadequate access to quality health care, thus allowing industrial development and production sites to become important foci of transmission. The altered local vector ecologies, and the changes in disease dynamics that changes affect, create challenges for under-resourced health care and vector-control systems.

Rainwater harvesting in residential homes is emerging as an important complement to centralized water supplies in urban centres around the world. Domestic rainwater harvesting systems provide a variety of benefits for water management and contribute to sustainable and integrated urban water management. There are however risks associated with rainwater harvesting that requires appropriate mitigation. One such risk is that systems can become breeding grounds for mosquitoes. This can constitute a significant health risk through the spread of mosquito-borne diseases (i.e. arbovirus and malaria). This paper explores the extent to which mosquitoes breed in rainwater harvesting systems as well as the effectiveness of different risk mitigation actions. Data were sourced from a large-scale domestic rainwater tank inspection survey undertaken in Melbourne and were analysed using simple Bayesian Network models. The observed rate of mosquito breeding was too high and was identified as a serious concern for health officials and water managers. The most common access routes into the tank system were found to be through the tank inlet or overflow. By exploring different system set-ups it was found that in order to mitigate the risk of mosquito breeding in tanks, all potential access routes must be adequately sealed. The complete eradication of mosquitos in rainwater tanks, however, may need further investigation, as 4% of systems with adequate protection at the inlet and overflow were still found to have mosquitoes in them.

There are varying ranges of habitats that have different characteristics of water for the breeding of mosquito. A house-to-house cross-sectional entomological survey was carried out at peridomestic area to detect larval breeding sites. Aedes albopictus was the predominant species in the container-breeding habitats. Most of the breeding habitats were class into high level of larval density. Turbidity, pH, TOC, magnesium, calcium and sodium is among the characteristics that shows a significant difference with the larval density and species composition respectively. As conclusion, characteristics of the mosquito breeding area can affect the larval density and give impact on the quality of life.

International audience; Mosquito-borne diseases like Rift Valley Fever and Malaria that cause serious health threat to human and livestock populations are known to correlate with the tremendous increase of associated mosquito vectors following periods of widespread and heavy rainfall. In the Barkedji area, Senegal, rainfall occur only during the July–October wet season, and mosquito breeding sites are provided by relatively small temporary ponds, which account for the vast majority of the water surfaces during the rainy season. Given that rain fed ponds play a key role in the epidemiology of the mosquito-borne diseases, we have developed an approach allowing to model the flooding/drying dynamics of rain fed ponds in the Barkedji area by combining the detection of ponds using optical remote sensing techniques, field data on a small set of monitored ponds and modeling of both the pond profile, shapes and the flooding/drying dynamics at the single-pond level for each pond in the entire region.As a result, we have computed on output the daily flooding/drying dynamics for each of the 1345 rain fed ponds detected in Barkedji area as a function of the daily rainfall in input. As dry and fluctuating ponds are less productive in mosquitoes, the ponds are characterizes in terms of flooding-drying fluctuations and of resistance to dryness by computing the total number of time per year a pond dries out and the pond lifetime, respectively. And, clusters of ponds with identical behavior, i.e., clusters of temporary, semi-permanent and permanent ponds, were subsequently identified.As a perspective, we show how this work can be used for modelling mosquito population dynamics and addressing the issues of associated impacts of climate change.

Summary: Dengue is a major problem in southern Thailand. Objectives: (1) To determine students’ basic knowledge of dengue and (2) to examine the larval indices in primary schools and in the students’ households. Methods: This study employed a cross-sectional quantitative and qualitative approach involving meetings with students, discussions with groups of teachers, a questionnaire investigating students’ basic knowledge of dengue, and a survey of the larval indices in primary schools and in the students’ households. The study consisted of three stages: (1) community preparation, (2) data collection and analysis, and (3) feedback. Results: A total of 306 students (from primary education levels 4–6) from five primary schools in the community were included in the study. Of a total of 15 items on the basic dengue questionnaire, only five were answered correctly by more than 80% of the students. Most of the knowledge items showed statistically significantly different distributions of correct, incorrect, and unknown answers (P ≤ 0.05, P ≤ 0.01, and P ≤ 0.001). The larval indices surveyed in the five schools and in 302 student households showed a high risk of dengue, with high indices in the five schools (Breteau Index: BI = 200; House Index: HI = 60; and Container Index: CI = 7.94) and in the students’ households (BI = 754; HI = 77; and CI = 35). Conclusion: Risk factors for dengue were related to the students’ basic knowledge of dengue and to the larval indices in both the schools and the students’ households. Additionally, a coordinated effort will be required to eliminate Aedes aegypti mosquito breeding sites in the community. Keywords: Risk factors, Dengue, Primary school, Basic knowledge of dengue, Southern Thailand

Increased incidence of malaria in an Air Force Station in western India in 1994 was investigated by means of an epidemiological survey. The survey was conducted from 17 October to 20 October 1994. It revealed that the station had ecological conditions and topography favouring mosquito breeding. For 1994 the annual parasite incidence was 3.29 and annual blood examination rate was 26.4 per cent. Active parasitological survey revealed 2 cases of asymptomatic parasitaemia. The survey also revealed that the outbreak was due to combination of natural forces and laxity in implementing existing anti-malaria activity.

Surface agents to smother mosquito breeding sites have been used extensively for mosquito larval control. Such agents range from oil films and chemical monolayers, to expanded polystyrene beads(1,2). Here, Lu Bao-lin discusses the use of Azolla - a floating fern - for a similar effect. The fern has the additional advantage of providing a useful source of green manure as a crop fertilizer.

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