BEIJING – Following a cluster of cases among relatives, experts from the U.N. health agency are examining whether the H7N9 bird flu virus is spreading among humans but downplayed fears of a pandemic Friday.
“What we don’t know is the size of the iceberg under this tip,” said Michael O’Leary, the World Health Organization’s representative in China, after revealing details of three families who have shown possible human-to-human transmission.
O’Leary was speaking as 15 global international health experts began a weeklong mission in Beijing and Shanghai to investigate the H7N9 strain, which has killed 17 people and sickened 70 others so far.
“The primary focus of the investigation is to determine whether this is in fact spreading at a lower level among humans. But there is no evidence for that so far except in these very rare instances,” he added.
He said one family in Shanghai has shown evidence of more than one member being infected with the deadly strain. In the two other clusters, one family member was infected while the other had “clinically similar and presumed H7N9.” O’Leary said investigators are trying to determine whether the family members were infected with the virus from the same source, or from each other.
Almost all of the reported cases have occurred in Shanghai and four nearby provinces.