Regional dengue activity is variable. Malaysia continues to report a greater number of reported cases in 2014 compared to 2013, for the same time period. However, cases appear to be decreasing. Singapore has reported a similar number of cases in 2014 compared to 2013. Australia, Cambodia, Lao PDR, the Philippines and Viet Nam reported lower levels of dengue activity in 2014 compared to 2013.
Dengue virus infection in the Pacific Region High level of dengue activity is being observed in Fiji, French Polynesia, Solomon Islands and Tuvalu. Dengue virus serotype 3 (DENV-3), to which a large proportion of the population of the Pacific Islands is likely to be susceptible has been recently isolated in the Region and is now co-circulating with serotype 1 (DENV-1). DENV-3 has recently reemerged in several countries and territories in the South Pacific after nearly 20 years.
WHO is closely monitoring the situation in the Region, especially with regard to serotype circulation.
In Fiji, the outbreak since last December has affected over 20,000 individuals, including 13 deaths. Most cases have occurred in the Central Division. The Ministry of Health, in collaboration with other government sectors and health partners including WHO, has embarked on controlling and responding to the outbreak.
In French Polynesia, a dengue outbreak is ongoing. Since February 2013, there have been 1,906 positive cases of dengue as of 4 April 2014. In the month of March, all cases serotyped were dengue serotype-1 and the rate of hospitalization and severe cases has increased.
In Solomon Islands, 754 cases of dengue have been reported since January 2014 (138 additional cases reported this week). A post disaster epidemic surveillance system was set up in Honiara and Guadalcanal Province following flash flooding on 4 April 2014.
Rapid reference laboratory testing of samples by the Institut Louis Malarde, French Polynesia, confirmed the dengue serotype as type 3. As this is the same type that caused the large dengue outbreak in 2013, and because infection with one serotype results in life-long immunity to that specific serotype, the likelihood of an explosive and widespread outbreak is lower than if another serotype was identified.
In Tuvalu, a dengue outbreak is occurring with nine confirmed cases out of 43 dengue-like illness (DLI cases), as of 10 April 2014. The Ministry of Health has embarked on an extensive clean-up campaign.