Dengue virus infection--the Malaysian experience

Area of Science:

• Epidemiology
• Infectious Diseases
• Virology

Background:

• Dengue fever has been a notifiable disease in Malaysia since 1973.
• The disease pattern has shifted from biennial outbreaks to a yearly increasing trend.
• The largest outbreak occurred in 1996, with 14,255 cases and 32 deaths.

Purpose of the Study:

• To analyze the changing patterns of dengue disease in Malaysia.
• To investigate the trends in case fatality rates and serotype predominance.
• To document the evolving clinical spectrum and multisystem involvement in dengue.

Main Methods:

• Retrospective analysis of dengue case data in Malaysia.
• Review of case fatality rates correlated with predominant dengue serotypes.
• Documentation of clinical manifestations, including liver and neurological involvement.

Main Results:

• Dengue cases show a yearly increasing trend, with a significant outbreak in 1996.
• Case fatality rates varied significantly (1.29% to 10.43%) depending on the predominant serotype (Dengue type 1 vs. Dengue type 3).
• Severe manifestations, including liver involvement (fulminant hepatitis) and neurological complications (neurovirulence), are increasingly observed, with Dengue type 3 implicated.

Conclusions:

• Dengue epidemiology in Malaysia is evolving, with an increasing yearly incidence.
• Dengue serotypes 2 and 3 are associated with severe disease patterns and multisystem involvement.
• There is a notable shift in mortality, with over 50% of deaths occurring in patients over 15 years since 1982.