Mortality rate for H5N1 lowers over the last five years

A recent study by German scientists has shown that the global mortality rate of H5N1 avian influenza has declined somewhat in the last 5 years.

The study, conducted by a team from the Robert Koch Institute, Germany’s national disease-control agency, also demonstrated that the risk of dying from H5N1 increased sharply each day that treatment was postponed and that the majority of patients were women, according to CIDRAP News.

The scientists, whose work was published in the online journal Eurosurveillance, compiled and analyzed public data on cases reported from September 2006 to August 2010.

"With this study, we show that data from the public domain yield important epidemiological information on the global AI [avian influenza] situation," they wrote, CIDRAP News reports. "Open access to analyzable data might accelerate the identification and implementation of research questions and surveillance priorities and thus enhance our understanding of—still mostly fatal—AI in humans.”

The authors added that they recommend creating a “line list” of human H5N1 cases in order to further understand the disease and enhance the detection of changes in its epidemiology.

Public sources were exclusively utilized in the study, including information from the World Health Organization, the European Center for Disease Prevention and Control, ProMed and Reuters AlertNet. The team found 294 cases over the last five years, including 235 confirmed by the WHO, 35 considered probable and 24 suspected.

Four countries accounted for 10 or more cases each. There were 98 in Egypt, 82 in Indonesia, 18 in China and 25 in Vietnam, CIDRAP News reports.

Overall, 56 percent of the confirmed cases resulted in death. Consistent with previous reports of the top four countries, the death rate was highest in Indonesia at 87 percent and lowest in Egypt at 28 percent.