Dengue haemorrhagic fever: recent advances.

Diseases caused by the dengue viruses comprise of the classical form of dengue fever (DF) and the more severe dengue haemorrhagic fever (DHF) sometimes accompanied by the dengue shock syndrome (DSS). These diseases continue to pose an important public health threat in many parts of the tropical world 3 2 . In recent years, DF outbreaks have occurred in India (1982) and Northern Australia (1981) and DFIDHF outbreaks in the Pacific Islands (1979), Vietnam and China (1979-80), Thailand (1980) and Indonesia (1982). In 1982, Malaysia suffered what was probably the biggest outbreak in the country's history with 3005 cases of DFIDHF and 35 deaths. A very significant event also occurred in Cuba in 1981 where a very large epidemic of DF/ DHF was recorded with 116,143 cases (of which 10,000 were DHF) and 158 deaths. This event represents the first occurrence of DHF outside the Southeast Asian region and illustrates the potential threat of severe dengue disease in parts of the world where dengue viruses circulate but which, for the time being, do not have cases of DHF among affected individuals. Despite the obvious importance of the problem, many unknowns remain in the various aspects of DHF and much more intensive research needs to be done.