An overview on severe acute respiratory syndrome (SARS).

Severe acute respiratory syndrome (SARS) is a newly emerged infectious disease that has caught the medical profession by surprise in 2003. The major clinical features include persistent fever, chills/rigor, myalgia, malaise, dry cough, headache and dyspnoea but diarrhea occurs in 40-70% of patients after hospital admission. Respiratory failure is the major complication of SARS; at least half of the patients require supplemental oxygen during the acute phase whereas about 20% of patients progress to acute respiratory distress syndrome requiring invasive mechanical ventilatory support. In contrast, the severity is generally mild in infected young children. Due to our limited understanding of this new disease, treatment of SARS was empirical in 2003. Protease inhibitor (Lopinavir/ritonavir) in combination with ribavirin may play a role as antiviral therapy in the early phase whereas nelfinavir is a promising alternative. The role of interferon and systemic steroid in preventing immune-mediated lung injury deserves further investigation. In addition, other anti-viral treatment, RNA interference, monoclonal antibody, synthetic peptides, and vaccines are being developed. Rapid diagnosis, early isolation, and good infection control measures are important in preventing spread of the infection.