(another flu post!)
Data published by the WHO states that the H5N1 bird flu has a mortality rate of almost 59% (out of a total of 586 cases since 2003)--a rate that is more than worryingly high. However, a new study from the Mount Sinai School of Medicine has found evidence that perhaps this rate is incorrect. In their study, they screened blood samples from more than 12,000 people in Europe, Asia, and Africa, and found that 1-2 percent of the samples showed signs of bird flu infection, but that none of the individuals died from bird flu, and most never even sought treatment. This data suggests that many more people have been infected with bird flu than according to the WHO, and thus that the bird flu mortality rate could be much lower than previously thought.
This discrepancy in numbers makes sense when you consider that in order for the WHO to classify someone as sick, they have to have a fever and be sick enough to go to a hospital and be tested specifically for the virus. Individuals who are already that sick are more likely to die, which raises the mortality rate as a result.
Takeaway: the article suggests a population-wide study of infection rates and symptoms in order to find out exactly how serious this still-dangerous virus really is.