RESUMEN
Background: Pandemic flu (H1N1 ) strongly affected southern Chile during2009. Aim: To report the logistic and organizational changes implemented at a regional hospital to face the pandemic. Material and Methods: All patients with flu like disease that were hospitalized, were prospectively enrolled at the Puerto Montt hospital. A nasopharyngeal aspirate was obtained in all for influenza virus A and B direct immunofluorescence and polymerase chain reaction (PCR). All epidemiological and clinical data of patients were recorded. Results: Between May 29 and July 7, 2009, 184 adults were admitted to the hospital and in 117patients aged 41 ± 18 years (56 percent females ), direct immunofluorescence was positive for influenza. In 67 of these patients PCR did not confirm the disease. These unconfirmed patients had a mean age of 49 ± 19 years (p < 0.01, compared with confirmed cases) and had a lower frequency of fever, rhinorrhea and chills. No significant differences in the incidence of community acquired pneumonia or chest X ray findings were observed between confirmed and unconfirmed cases. Hospital stay was over 15 days in 14 percent of confirmed cases and 5 percent of unconfirmed cases (p = 0.03). Fifteen patients, aged 53 ± 18 years, died. Conclusions: Low sensibility of direct immunofluorescence and delay in obtaining PCR confirmation of influenza posed a problem for the management of these patients.