The World Health Organization on Friday said the child with H5N1 bird flu reported by Australia last month had traveled to Kolkata, India, and the family said they did not have any known exposure to infected people or animals while there.
The WHO said on Friday that the child, Australia's first case of H5N1 in a person, had traveled to Kolkata from Feb. 12 to Feb. 19 and returned to Australia on March 1.
The child was hospitalized on March 2 and remained there for more than two weeks. No close family contacts in Australia or India developed symptoms, as of May 22, the WHO said.
The WHO said genetic sequencing showed the virus was subtype H5N1 and part of a strain that circulates in Southeast Asia and has been detected in previous human infections and in poultry.
Amesh Adalja, an infectious disease expert at the Johns Hopkins Center for Health Security, said while it would be difficult to do months after the fact, an investigation is needed to see if the child was in contact with poultry or other birds, or if there was an outbreak of this version of H5N1 nearby.
"H5N1 viruses do not transmit efficiently between humans and I suspect there’s an occult animal exposure that led to the infection," Adalja said.
