Epidemiology of fatal cases associated with pandemic influenza reported in Yemen

Abstract

Objectives: This study describes the incidence of all fatal cases associated with Pandemic Influenza A (H1N1) in Yemen. It sets out to highlight the factors associated with poor prognosis *The authors declare that they have no competing interests. to enhance the implementation of prevention and control programs. Methods: The study is based on retrospective analysis of available data until 14 March 2010, as compiled by the disease control and surveillance team in Yemen. Results: Between 16 June 2009 and 14 March 2010, a total of 33 laboratory-confirmed death cases associated with pandemic influenza A (H1N1) were reported to the Diseases Control and Surveillance in the Ministry of Public Health and Population. During this period, a total of 6049 suspected influenza A (H1N1) cases were recorded. With this denominator, the case fatality rate (CFR) was 0.54%. During June through August, H1N1 confirmed cases were infrequently detected, including only 30; however, from September through December, over 200 confirmed cases were reported each month. Of the 33 cases recorded, 25 were male (76%) and 8 were female (24%), male to female ratio being 3:1. Overall median age of the death cases was 30.8 years (range 1 - 55). The most common diagnosis upon admission was pneumonia. Out of the deaths, twenty five (75.8%) had no documented underlying diseases. Chronic cardiovascular disease (9.1%) was the most commonly reported disease and 2 deaths (6.1%) were recorded as pregnant women. Conclusions: The most common diagnosis upon admission was pneumonia. Chronic cardiovascular diseases were the most commonly reported underlying conditions, while the most identified risk factor was pregnancy. These findings should be taken into consideration, when vaccination strategies are employed.