Fatal dengue hemorrhagic fever in Cuba, 1997

Area of Science:

• Virology
• Epidemiology
• Clinical Pathology

Background:

• Cuba experienced a dengue epidemic in 1997 after 15 years without activity.
• This epidemic included 3,012 confirmed cases, 205 of which were severe Dengue Hemorrhagic Fever/Dengue Shock Syndrome (DHF/DSS).
• 12 fatalities from DHF/DSS were reported, prompting a detailed investigation.

Purpose of the Study:

• To present the clinical, serologic, and virologic findings of 12 fatal DHF/DSS cases during the 1997 Cuban dengue epidemic.
• To analyze the risk factors and characteristics of severe dengue in adults.

Main Methods:

• Serum and necropsy samples were analyzed using viral isolation and polymerase chain reaction (PCR).
• Serological testing included IgM capture enzyme-linked immunoassay (ELISA) and ELISA inhibition method (EIM).

Main Results:

• All 12 fatal cases met DHF/DSS criteria; patients were adults, with women more frequently affected.
• Key warning signs included abdominal pain and persistent vomiting, with clinical deterioration around day 3.75.
• Dengue II virus was confirmed in all cases, with IgM antibodies indicating secondary infections in most. Viral RNA was detected in multiple organs.

Conclusions:

• Adults with primary dengue infection are at risk of severe DHF if infected with a different serotype.
• The study highlights the clinical and pathological features of fatal DHF/DSS in adults during a dengue type II epidemic.