2009 H1N1 Influenza Infection-Related Hospital Admissions: A Single Center Experience with Adult Patients in West Texas

Background . Clinical information collected during the first wave of influenza pandemics may provide important projections about disease activity during subsequent waves. Methods . We performed a retrospective study of hospitalized patients with 2009 H1N1 influenza infection during the second wave and compared our findings with literature reports from the first wave. Results . There were 31 admissions, including 15 to the intensive care unit (ICU). Twenty-five patients (81%) had at least one chronic medical condition; 12 patients (39%) were obese. Thirty-three percent of the ICU patients and 75% of the non-ICU patients were admitted within 48 hours of symptom onset ( P = 0.03 ). Infiltrates on CXR were seen in 60% of the ICU group and 19% of the non-ICU group within 48 hours of admission ( P = 0.03 ). Forty-three percent of the ICU patients and 71% of the non-ICU patients received oseltamivir within 48 hours of illness. All non-ICU patients survived; 73% of the ICU patients survived ( P = 0.043 ). Conclusions . Our patients in the second wave resembled patients reported from the first wave of the 2009 pandemic and had similar mortality rates. Delayed medical attention possibly explains the high number of ICU admissions in our study.