Dengue virus (DENV) infection is a global health threat affecting at least 3.6 billion people living in more than 125 countries in the tropics and subtropics. It is among the most important arthropod-borne diseases. All four dengue virus serotypes (DENV-1, DENV-2, DENV-3 and DENV-4) can cause dengue. The disease can present as a mild self-limiting illness, dengue fever (DF), or as the more severe forms of the disease, dengue hemorrhagic fever (DHF) and dengue shock syndrome (DSS). The World Health Organization (WHO) 2009 guidelines classify patients into three groups; dengue without warning signs, dengue with warning signs and severe dengue. Clinical manifestation of severe dengue includes severe bleeding, severe organ involvement and severe plasma leakage. Most dengue deaths are associated with DHF/DSS (WHO 1997 guidelines) and severe dengue (WHO 2009 guidelines).
DF and DHF were first documented in Malaysia in 1902 and 1962, respectively. A major dengue epidemic was recorded in 1973, and since then dengue has become endemic in Malaysia with major outbreaks occurring every 3–4 years. There were a number of reports describing the clinical features and risk factors associated with the severe manifestations of dengue and dengue-related deaths during the first two decades following the 1973 epidemic. During this period, children were the most predominant group affected, hence contributed substantially to the clinical description of severe dengue. In the last two decades, however, the number of dengue cases had escalated exponentially. There were 48,846 cases and 98 deaths in 2007 in Malaysia with those aged 15–35 years old contributing to at least 48% of the total number of dengue cases. The trend of higher percentage of adults contracting dengue has also been reported in other dengue endemic countries. This review of fatal cases of dengue infection was undertaken in light of this changing epidemiology of dengue in Malaysia and in this region.