- Jan 11, 2006
Human bird flu cases may be more common than reported
But the infections were mild, suggests a study by Swedish and Vietnamese researchers
WASHINGTON - HUMAN cases of bird flu may be both more common but less lethal than has been reported, say Swedish and Vietnamese researchers.
A new study suggests that thousands of mild human cases of the H5N1 avian influenza have occurred throughout the two-year outbreak in Vietnam - the epicentre of the bird flu problem.
Experts said the study provides a strong counterpoint to growing fears about the infectiousness of avian influenza. Indeed, the virus can be so mild in some people that they easily shake the infection without medical attention.
Dr Anna Thorson of the Karolinska Institutet in Stockholm, who led the study, said that the study, which did not take blood samples from its subjects, cannot prove these people were infected with bird flu. But it suggests that infections may be going undetected.
'The verified human cases of highly pathogenic avian influenza in Vietnam may represent only a selection of the most severely ill patients,' her team wrote in their report, published in the Archives Of Internal Medicine.
H5N1 has killed at least 76 people since 2003 and experts fear it could acquire the ability to pass easily from person to person, sparking a pandemic that could kill millions.
The team decided to gather evidence that avian flu may have been circulating undetected in Vietnam.
The Swedish researchers interviewed nearly 46,000 people from Vietnam, where there have been 87 cases of bird flu. They found that more than 8,000 had had flu-like symptoms and up to 750 cases could have been due to sick birds.
Dr Thorson said the study - the largest one carried out on bird flu to date - suggests that the strain does not kill half of people infected with it...
On a separate note, here's a good, simple article addressing the FAQs about bird flu.