A wave of H7N9 bird flu in China that has spread to people may have the potential to emerge as a pandemic strain in humans, scientists said on Wednesday.
The H7N9 virus, one of several strains of bird flu known to be able to infect humans, has persisted, diversified and spread in chickens across China, the researchers said, fueling a resurgence of infections in people and posing a wider threat.
"The expansion of genetic diversity and geographical spread indicates that, unless effective control measures are in place, H7N9 could be expected to persist and spread beyond the region," they said in a study published in the journal Nature.