Journal Article

Clinical Features of Human Influenza A (H5N1) Infection in Vietnam: 2004–2006

Long, Hoang Thuy, Hien, Tran Tinh, Farrar, Jeremy, Taylor, Walter R. J., Horby, Peter, Tung, Cao Viet, Hien, Nguyen Tran, Chau, Ngo Quy, Khang, Dinh Duy, Wertheim, Heiman, Liem, Nguyen Thanh, Mai, Le Quynh, Hien, Nguyen Duc

2009

Overview

Background. The first cases of avian influenza A (H5N1) in humans in Vietnam were detected in early 2004, and Vietnam has reported the second highest number of cases globally. Methods. We obtained retrospective clinical data through review of medical records for laboratory confirmed cases of influenza A (H5N1) infection diagnosed in Vietnam from January 2004 through December 2006. Standard data was abstracted regarding clinical and laboratory features, treatment, and outcome. Results. Data were obtained for 67 (72%) of 93 cases diagnosed in Vietnam over the study period. Patients presented to the hospital after a median duration of illness of 6 days with fever (75%), cough (89%), and dyspnea (81%). Diarrhea and mucosal bleeding at presentation were more common in fatal than in nonfatal cases. Common findings were bilateral pulmonary infiltrates on chest radiograph (72%), lymphopenia (73%), and increased serum transaminase levels (aspartate aminotransferase, 69%; alanine aminotransferase, 61%). Twenty-six patients died (case fatality rate, 39%; 95% confidence interval, 27%–51%) and the most reliable predictor of a fatal outcome was the presence of both neutropenia and raised alanine aminotransferase level at admission, which correctly predicted 91% of deaths and 82% of survivals. The risk of death was higher among persons aged ⩽16 years, compared with older persons (P<.001), and the risk of death was higher among patients who did not receive oseltamivir treatment (P=.048). The benefit of oseltamivir treatment remained after controlling for potential confounding by 1 measure of severity (odds ratio, 0.15; 95% confidence interval, 0.026–0.893; P=.034). Conclusion. In cases of infection with Influenza A (H5N1), the presence of both neutropenia and raised serum transaminase levels predicts a poor outcome. Oseltamivir treatment shows benefit, but treatment with corticosteroids is associated with an increased risk of death.

• Publisher: The University of Chicago Press,University of Chicago Press,Oxford University Press
• Subject: Adolescent / Adult / Alanine transaminase / Antiviral Agents - therapeutic use / Articles and Commentaries / Aspartate aminotransferase / Avian flu / Biological and medical sciences / Bleeding / Chest / Child / Child, Preschool / Confidence intervals / Corticoids / Cough / Data processing / Diarrhea / Diarrhea - etiology / Diseases / Dyspnea / Female / Fever / Fowl plague / H5N1 subtype influenza A virus / Hemorrhage - etiology / Hospital admissions / Hospitals / Human influenza / Human viral diseases / Humans / Infant / Infection / Infections / Infectious diseases / Influenza A / Influenza A virus / Influenza A Virus, H5N1 Subtype - isolation & purification / Influenza, Human - complications / Influenza, Human - mortality / Influenza, Human - pathology / Influenza, Human - virology / Lung / Lung - diagnostic imaging / Lung - pathology / Lymphopenia / Lymphopenia - etiology / Male / medical records / Medical sciences / Middle Aged / Mortality / Mucosa / Neutropenia / Neutrophils / Older people / Oseltamivir / Oseltamivir - therapeutic use / Radiography / Respiration / Retrospective Studies / Risk Factors / Survival / transaminase / Transaminases - blood / Treatment Outcome / Vietnam / Viral diseases / Viral diseases of the respiratory system and ent viral diseases / Viruses / Young Adult