Assessing potential countermeasures against the dengue epidemic in non-tropical urban cities.

Background: Dengue is a common mosquito-borne viral disease epidemic especially in tropical and sub-tropical regions where water sanitation is not substantially controlled. However, dengue epidemics sometimes occur in non-tropical urban cities with substantial water sanitary control. Using a mathematical model, we investigate what conditions can be important for a dengue epidemic to occur in an urban city such as Tokyo, where vectors are active only in summer and there are little number of vectors around hosts.

Estimating the probability distribution of the incubation period for rabies using data from the 1948-1954 rabies epidemic in Tokyo.

Data of 98 rabies cases in dogs and cats from the 1948-1954 rabies epidemic in Tokyo were used to estimate the probability distribution of the incubation period. Lognormal, gamma and Weibull distributions were used to model the incubation period. The maximum likelihood estimates of the mean incubation period ranged from 27.

[Competition between Aedes aegypti and Aedes albopictus larvae in the laboratory].

This study had the aim of evaluating the effects of intra and interspecies larval competition between Aedes aegypti and Aedes albopictus, survival of larvae time taken to develop and wing length. The experiment was carried out with three densities and five proportions of the species. Aedes aegypti survival was greater than Aedes albopictus survival at intermediate density, while it was lower at high density.

[Vertical and seasonal distribution of Anopheles (Kerteszia) in Ilha Comprida, Southeastern Brazil].

Objective: Anopheles bellator e An. cruzii are vectors of the so-called bromeliad-malaria, typical of conserved areas. The objective was to evaluate the seasonal and vertical distribution of these anophelines, aiming at assessing the risk of malaria transmission.

[Seasonal variation of Aedes aegypti and Aedes albopictus in a city of Southeastern Brazil].

Objective: To assess the seasonal variation of Aedes aegypti and Aedes albopictus and to estimate the association between the species abundance and abiotic factors.

Methods: Tire-traps were kept for a period of 15 days monthly in an urban area of the city of Potim in the state of São Paulo, Southeastern Brazil, from November 2002 to October 2003. Samples of immature forms were followed up under laboratory conditions for 29 days and species were identified.