No need to panic

"Although we do not know the source of infection, at this time there is no evidence of sustained human-to-human transmission," the World Health Organization (WHO) representative in China Dr. Michael O'Leary said at a news conference held by the NHFPC on April 8.

In some of the H7N9 cases, the infected people were found to have had contact with animals, he said, citing the appearance of the virus in pigeons in a Shanghai marketplace.

Though he admitted these cases indicate that the virus may have crossed from animals to humans, O'Leary said that the WHO does not deem it necessary at present to introduce screening measures at ports of entry or adopt any restrictive measures on tourism and trade.

He said that the public should maintain good hygiene and only eat properly cooked meat.

China has started research for the development of vaccines for the H7N9 bird flu virus, said Liang Wannian, Director of the H7N9 Influenza Prevention and Control Office under the NHFPC, at the press conference on April 8.

However, complications in the development and manufacturing process mean it may take about six to eight months before the vaccines can be distributed.

Liang said the decision to put the vaccines into production will depend on whether the virus can mutate to become human-to-human transmissible.

In its first edition of the H7N9 diagnosis and treatment guidance released on April 3, the NHFPC recommended the use of antiviral drugs, including neuraminidase inhibitors as well as some traditional Chinese medicine, on patients.

The CAS announced on April 9 that it has started researching how humans can avoid contracting the H7N9 virus. The project with joint efforts from nine CAS institutes focuses on H7N9's origin, mutations, pathogenesis and interactions with hosts, among other aspects.

These institutes will conduct scientific evaluations on immune system responses to the virus as well as the performances of antiviral drugs in the hope of accelerating the development of new medicines against the virus.