The World Health Organizaton (WHO) and experts on bird flu remain very concerned about a potential bird flu pandemic. Warnings have been raised by infectious disease experts
over the past few months that bird flu could start to show signs of spreading from human to human and then explode into a worldwide pandemic killing tens of
millions of people around the world. Naturereports that recently in Vietnam scientists were concerned when many influenza patients were testing positive for exposure to H5N1. This caused WHO to consider raising the threat level of a global pandemic from its current level
of 3 to a 4 or even a 5. Later studies indicated that the H5N1 exposure
data may have been false so WHO decided not the raise the alert.
However, confusion remains about the "false positive" test results for H5N1 exposure in multiple influenza patients.
The scare was triggered a few weeks ago when several research groups visiting
Vietnam filed preliminary reports that many people with mild cases of influenza - and those in contact with them - were testing positive for the deadly avian flu strain H5N1. This suggested that there was widespread human-to-human transmission of the virus.
Subsequent tests have so far failed to confirm this, and WHO spokesman Dick
Thompson is keen to play down the incident. "It was just unpublished information provided to us in preliminary form that spurred an investigation," he says. "We thought about upgrading the alert. We looked at it fast and strongly, and based on that decided not to upgrade."
