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.

Prevalence of hepatitis E virus (HEV) infection in wild boars (Sus scrofa leucomystax) and pigs in Gunma Prefecture, Japan.

The prevalence of hepatitis E virus (HEV) infection in wild boars and pigs in Gunma Prefecture, Japan, was serologically and genetically examined. The positive detection rates of anti-HEV IgG and HEV RNA in the wild boars were 4.5% (4/89) and 1.

Sequence and phylogenetic analysis of the nucleoprotein (N) gene in measles viruses prevalent in Gunma, Japan, in 2007.

In 2007, relatively large outbreaks of measles occurred in the Kanto region of Japan, including Gunma Prefecture. We performed sequence and phylogenetic analysis of the nucleoprotein gene (N gene) of measles viruses from 3 measles patients in this area in May 2007. The N gene sequences of the present strains were identical to each other, and phylogenetic analysis showed these viruses were classified into genotype D5.