Dengue Situation Updates
as of 26 February 2014
Regional dengue activity is variable. Australia, Malaysia and Singapore have been experiencing a greater number of reported cases in 2014 compared to 2013, for the same time period. The recent trend increased in New Caledonia and Lao PDR however, reported cases remained lower than 2013, for the same time period. The recent trend continued to decrease in Cambodia, Philippines and Viet Nam.
Lao PDR experienced a large dengue year in 2013, peaking in August 2013. However, in early 2014, dengue activity remains low, and substantially lower than during the same time period in 2013.
Malaysia is experiencing an outbreak of dengue. In February 2014, dengue activity is about 4 times higher than 2013, for the same time period.
Singapore has also been experiencing an increased level of dengue activity. In early 2014, dengue activity is 1.5 times higher than 2013, for the same time period.
Dengue virus infection in the Pacific Region
High level of dengue activity is being observed in Fiji, New Caledonia, Vanuatu and Cook Islands.
In Fiji, as of 16 Feb 2014, there were more than 6659 suspected including 2589 confirmed cases of dengue. There are two confirmed and two suspected dengue deaths. The Central Division reported the highest number of suspected cases of with 2112 cases reported. DENV-3 has been isolated. The number of cases is expected to continue to increase in the coming months. WHO and SPC have provided technical and financial support to assist in the confirmation and response to the outbreak. This includes, the provision by WHO of 10,000 dengue test kits. MOH are responding to the situation with control measures including cleaning, discarding water containers to remove mosquito breeding places in addition to other vector control activities.
In New Caledonia, since Sept 2013, there have been more than 70 dengue cases as of 20 Feb, with an increasing proportion of endemically transmitted disease reported, DENV-3 has been isolated in addition to DENV-1 (isolated in an imported case). Arboviral surveillance and public health response measures have been reviewed and strengthened.
In Vanuatu, as of 18 Feb 2014, a total of 765 cases were reported, including 85 confirmed cases of dengue. The total cases reported in 2-9 Feb was 111 cases, slightly lower than the previous week of 27 Jan to 1 Feb at 219 cases. The Ministry of Health is continuing to activate enhanced surveillance in Port Vila and the main centers throughout the country. With the support of WHO and other external partners, case management capacity and prevention intervention have been strengthened in Port Vila and Luganville. Efforts have been taken by the MOH to control and reduce the dengue outbreak.
In Cook Islands, as of 25 February 2014 there have been 47 cases of dengue-like illness of which 36 were RDT positive. All cases are from Raratonga, there have not been any hospitalizations. Specimens have been sent to French Polynesia for serotyping and results are pending.
In French Polynesia, the dengue situation appears to be improving with a decline in cases reported each week after seeing an increasing level of dengue since mid-July 2013. As of 21 Feb 2014, the total number of cases is 1,724.
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 co-circulating with serotype 1 (DENV-1), although, a large proportion of the Pacific Island communities are likely to be immune to DENV-1 as it has been circulating in the Region for many years. Dengue virus serotype 3 has recently re-emerged in several countries and territories in the South Pacific after nearly 20 years. WHO is closely monitoring the situation in the Region.
Zika virus infection in the Pacific region
In French Polynesia, as of 21 Feb 2014, there were more than 8,500 suspected cases of zika virus infection reported by the health professionals sentinel network. Since late October, there were 301 confirmed cases. All islands of French Polynesia have been affected, and in all islands, the epidemic seems to have entered a phase of decline.
In New Caledonia, the Department of Health and Social Affairs detected the first indigenous case of zika virus infection on 19 Jan 2014. As of 20 Feb, there have been 95 confirmed cases of zika virus since 25 November 2013. Of these, 64/95 (67%) were locally transmitted cases and 31/95 (33%) imported from French Polynesia.
Zika virus infection is usually a mild disease; no hospitalizations directly related to acute infection have been reported. However, the etiology of a cluster of more severe patients with neurological or auto-immune symptoms in French Polynesia, of which some presented with GBS and a high titre of IgG against zika virus* still needs to be determined. Current public health surveillance and response measures aimed at arboviruses in New Caledonia were reviewed and strengthened and include implementing surveillance at the arrivals of all flights from French Polynesia. Surveillance and response capacities are strong and at this stage, WHO assistance has not been requested. WHO continues to monitor the situation closely.
* Surveillance de la dengue et du zika en Polynésie française Données actualisées au 24 janvier 2014
Table. Reported number of dengue cases in 2014 and 2013 (for the same time period), by country.* NA: Not applicable.
*Dengue reporting systems vary by country and any change in the surveillance system over time is not reflected in the above figures. Number of reported cases listed for 2014 and 2013 (or, if stated for 2013 and 2012) are for the same time period for each year.
**Recent trend is based on the 3 week moving average for countries reporting by week and monthly comparisons for the last complete month for countries reporting by month.
***Australia: Aedes aegypti and Aedes albopictus are present only in Northern Queensland and Torres Strait Islands
^ No available data in 4 regions
Chikungunya Update (As of 2 October 2013)
In recent times, the Western Pacific Region has been experiencing increased reports of chikungunya. In Singapore, 704 cases have been reported up to 21 September in 2013 relative to 9 cases for the same time period in 2012; weekly trend has been increasing for the last several weeks, with 49 cases reported during 15-21 September 2013. In Cambodia, chikungunya reemerged and was detected February-March 2012, soon to be followed by the detection and report of chikungunya for the first time in neighboring Lao PDR, May- September 2012 (see WPSAR: http://ojs.wpro.who.int/ojs/index.php/wpsar/article/view/192/252).
In the Oceania region, since chikungunya was reported February-June 2011 in New Caledonia, Papua New Guinea has reported a large outbreak in June 2012 (see WPSAR: http://ojs.wpro.who.int/ojs/index.php/wpsar/article/view/96/287). In Australia, 107 cases were reported up to 30 September in 2013 relative to 9 in 2012 and 27 in 2011 for the same time period; currently, however, the trend in number of reported cases have been decreasing (18 cases in July, 8 cases in August and no cases reported in September 2013).
For further information on the dengue situation or its surveillance, please visit the following links:
- New Caledonia
- Pacific Islands and Territories