Solomon Islands

Solomon Islands: Dengue outbreak Emergency Plan of Action (EPoA) DREF Operation MDRSB005


A. Situation analysis

Description of the disaster

Since August 2016, an unusual increase in dengue-like illness, including the number of NS1 positive cases, has been observed through the National Syndromic Surveillance System of the Ministry of Health and Medical Services (MoHMS). An outbreak of dengue was declared by the Government of Solomon Islands for Honiara, the capital of Solomon Islands, and other parts of Guadalcanal province on 8 October 2016 and expanded to other provinces on 19 October. Surveillance for dengue has been enhanced in Honiara City Council and expanded to other private practitioners and Guadalcanal province.

Between 15 August and 16 October 2016, a total of 1,212 suspected dengue cases have been reported in Guadalcanal (including Honiara), Malaita and Isabel provinces (798 additional cases reported in situation report #3 of MoHMS for the week of 10-16 October 2016) and at least 3 dengue-like illness cases reported for Gizo City in Western Province. The upward trend shown in figure 1 below is also partly due to the enhanced surveillance sites in the country.

Nine hundred and eighty-three (81.1%) cases were reported in Honiara and 161 cases (13.3%) in Guadalcanal province, 67 cases (5.5%) in Malaita province and one case (0.1%) in Isabel province. Cases are widespread in all areas of Honiara including the positive NS1 cases where the population daily movement is dynamic across all areas of observation. East Honiara (37.2%) and Central Honiara (18.8%) were identified as the main areas where active transmission of dengue cases is occurring. A proportion (31.1%) of the cases in Honiara have incomplete address information thus it was difficult to identify which areas they were from. In Guadalcanal, 82% of the dengue cases that were reported within the central part of Guadalcanal (zone 6). There is no significant difference between the number of male and female dengue-like illness cases. The highest number of cases are those below 15 years old and those between 25 and 49 years old.

Historical evidence has shown that both dengue virus 1 and 2 had circulated in Solomon Islands in the past and reintroduction of both serotypes will likely spread in populated areas like Honiara and urban centres in other provinces (specifically Guadalcanal, Malaita and Western). DENV1 was documented to have circulated in Solomon Islands 14 years ago in 2002. This means those who are aged below 15 years are susceptible to this dengue strain which is somewhat consistent with the current surveillance findings that the largest number of cases is in this age group. It is likely that DENV1 is causing the current dengue outbreak. Also historical data have indicated DENV2 had circulated in Solomon Islands most recently in 1994. This may also mean that those who were born after 1994 or aged below 23 are likely susceptible to DENV2 infection. A sample of test negative dengue-like illness cases is also being tested for Chikungunya and Zika viruses.

Below are two key recommendations for public risk communication from MoHMS:

  • Public is advised to enhance personal protection against dengue and continue cleaning up of their home environment to reduce the breeding sites of mosquitoes transmitting this disease.

  • Public is also advised to seek health services if having dengue like signs and symptoms such as fever, rashes, muscles pain and red eyes