Influenza A (H1N1) 2009 pandemia. The experience of a tertiary care center in Beirut

In March 2009, a new influenza virus strain emerged, currently known as the 2009 pandemic H1N1 virus. The virus first appeared in Mexico and rapidly spread globally to reach a pandemic level in June of the same year. We describe here the experience of one major referral center in Beirut, Lebanon. The laboratory department at St. George Hospital University Medical Center received respiratory specimens from hospital wards, the emergency department, in addition to a considerable proportion collected directly from "outpatients" in the lab. We used the real time RT-PCR as our main diagnostic test. We collected data about the patients from the laboratory information system and from the hospital medical records department. From mid-August 2009 till the end of January 2010, a total of 1771 specimens were analyzed, with 948 (53.5%) returning positive for influenza A (H1N1) by RT-PCR. Only 79 patients with H1N1 infection required hospitalization. Most of H1N1 confirmed patients were children and adolescents aged 5 to 17 years and young adults between 25 and 44 years. The most common symptoms at presentation were: fever, cough, shortness of breath, chills, rhinorrhea or nasal congestion, as well as gastrointestinal symptoms. Twenty-three patients required ICU care and eight patients died. The vast majority had an uncomplicated course of illness and was managed in an outpatient setting. The percentage of positive tests during the pandemia was significantly elevated, although few patients experienced drastic clinical outcomes.