BEIJING -- China's top epidemiologist said Tuesday that the country is closely monitoring any possible new mutation of the A(H1N1) flu virus.

He said there is no need to panic. "Although the mutant A(H1N1) virus newly discovered by Japanese scientists reported higher chances of infection, there is no significant change in its nature compared with the original, because its fatality rate remains the same," Zeng said.

"I believe that the major concern for the countries affected by the spreading flu will possibly be virus mutation."

Zeng also said China's control and prevention measures may change, which will make the country's prevention work "more scientific, more specific and more cost-effective".

"Experts are considering these changes, which, I believe, will be announced very soon," he said, without giving further details.

As of 6:00 pm Tuesday, China reported 237 infections on the mainland with no fatalities.

The World Health Organization raised last week the alert level for A(H1N1) flu to six, its highest level, making it the world's first influenza pandemic in 40 years.

Zeng said the pandemic is still "moderate" and the current medical service system can cope well.

"There is no need to panic. With what we have done, I do not think the current flu epidemic will be as horrible as the one in 1918, which claimed around 40 million lives around the globe," he said.