Hospitalized patients with 2009 A H1N1 influenza in Puerto Rico, 2009

On May, 2009, Puerto Rico Department of Health traced the first patients hospitalized with 2009 A H1N1 influenza. We described the clinical characteristics of hospitalized and dead patients with 2009 A H1N1 in PR from May to December 2009. Using the cases reported on the Hospitalizations of Influenza Surveillance System, we collected clinical data on 325 patients who were hospitalized for at least 24 hours for influenza-like illness and who tested positive for the 2009 A H1N1 virus with the use of a real-time reverse-transcriptase–polymerase-chain-reaction assay. From the data of the 325 patients it was obtained that, 28% were admitted to intensive care units and 18% died. Forty-five percent of the patients were under the age of 19 years and 4% were 65 years of age or older. Forty-eight percent of the patients had at least one underlying chronic medical condition; some of these conditions included asthma (31%), diabetes, cardiovascular, pulmonary, renal, immunological, and cancer history. Twenty-two percent of the women were pregnant from which 9 died. Twenty-nine percent of the 209 patients who underwent chest radiography had findings consistent with pneumonia. Of the 259 patients that were administered antiviral drugs, 94% used oseltamivir. The 2009 A H1N1 influenza caused severe illness in patients, requiring hospitalization. Nearly one fifth of the 325 patients died, 9 of the deaths were pregnant women. Few severe complications were reported among persons 65 years of age or older and most of the hospitalizations occurred in children under 4 years. Patients seemed to benefit from early antiviral therapy.