Severe respiratory disease and its relationship with respiratory viruses in Colombia

Summary Background There are important gaps in our understanding of the epidemiology of respiratory virus infections in tropical countries. In September 2003, the Colombian epidemiological surveillance system was notified of several deaths from an acute respiratory disease (ARD). Methods In order to identify the agents associated with ARD cases, a clinical and laboratory-based surveillance system was implemented throughout the country. Results Between September 19 and December 31, 2003, 64 suspected cases of ARD were reported; of these reported cases, 21 (33%) died. Among 25 patients who underwent virus studies, influenza A (H3N2) ( n =7) was the most frequently identified agent. Other viruses included parainfluenza (4), influenza B (1), and respiratory syncytial virus (3). The peak occurrence of cases and deaths coincided with the replacement of the influenza A (H3N2) Panama strain, which had been circulating in Colombia since 1999, by three new influenza A (H3N2) strains (Korea, Fujian, and Wyoming). Conclusions This outbreak led to the strengthening of surveillance for respiratory viruses and to new national recommendations for influenza vaccination in Colombia.