DEN-3 – A threat the Pacific Islands need to consider

According to the Indonesian Ministry of Health, the deadly dengue fever outbreak has claimed 534 lives and has infected 44,027 in Indonesia from 1 January 2004 to 25 March 2004. Although all four serotypes are present, DEN-3 is the most common serotype circulating. As a comparison, in 2003, 14,071 cases of dengue were reported in Indonesia.

The Indonesian Ministry of Health reports that most of the dengue fever cases have been found in Jakarta, but the highest casualty rate has been recorded in central Java. At the end of March 2004, the outbreak may be in the decreasing phase in Jakarta, Jawa Tenggah and Nusa Tenggara Timur provinces. However, the number of monthly reported cases still appears to be on the rise in Jawa Barat, Bali, Sumatera Selatan, Lampung, Kalimantan Timur, Sulawesi Seltan and Nusa Tenggara Barat provinces.

As a response to the outbreak, the Indonesian government has launched intensive vector control activities, including larviciding, space spraying and mobilising communities to reduce Aedes breeding spots.

This dengue fever outbreak in Indonesia is of particular concern for Pacific Island countries and territories (PICTs). While some are still affected by the DEN-1 epidemic that started in 2000, and others are recovering from it, DEN-3 virus importation could mean the beginning of a new epidemic in the Pacific Islands region, as this serotype has not been seen for quite a few years. Outbreaks of dengue serotype 3 were reported in Niue in 1986, and between 1989 and 1996 in many PICTs (New Caledonia, Tuvalu, Wallis and Futuna, French Polynesia, Fiji Islands, Cook Islands and American Samoa).

As for other dengue serotypes, populations not previously infected by dengue serotype 3 (which includes all those born after the epidemic, now under the ages of 8 to 15, depending on the place) are all susceptible to it. A low but significant proportion of these dengue fever cases could turn into dengue shock syndrome/dengue hemorrhagic fever and possibly death. It has also been shown that the presence of severe cases of dengue fever may be higher when an outbreak occurs within six months to five years of the preceding one[1].

(sources of information about the dengue outbreak in Indonesia: Indonesian Ministry of Health and WHO)

Dr Tom Kiedrzynski