There are also no confirmed cases of an outbreak of low-pathogenic H5N2 avian flu virus among poultry in Taiwan, CDC Deputy Director Lin Ting said.

He added that there is no evidence that the H5N2 can jump species to infect humans.

As of yesterday, the CDC had received reports of eight suspected cases of H5N1 infections in humans. Two persons involved in the cases had visited China, one had visited Vietnam and five had been in close contact with poultry, Lin said.

"Examination results showed that five cases were seasonal influenza virus infections and the remaining three tested negative for any flu viruses," Lin said.

He stressed that none of the suspected cases were H5N1 infections.

Quoting data released by the World Health Organization (WHO), Lin said more than 60 percent of confirmed human H5N1 cases have had close contact with poultry.

He advised local people to avoid contact with wild birds or chickens when they travel to countries or areas where H5N1 outbreaks among humans or animals have been reported, particularly Hong Kong, China's Jiangsu province, Indonesia, Egypt and Cambodia.

Meanwhile, Lin said an outbreak of low pathogenic H5N2 avian flu is not uncommon among poultry. But the infection usually does not have a grave impact on animals. Even if the virus mutates to a high-pathogenic strain, it would only affect poultry, he said.

To date, Lin said, only a few Japanese officials working in animal quarantine jobs have tested positive for weak H5N2 antibodies after slaughtering chickens infected with the virus. "None of the workers have developed the disease, which indicates that H5N2 is unlikely to infect humans," he added.

Meanwhile, Magistrate Su Huang-chih of Tainan County categorically denied a local media report that there was an outbreak of avian flu in November in the southern county.

"The report is totally groundless.There has been no bird flu in Tainan County and not a single chicken has been killed as a result of the disease," Su said at a news conference that was also attended by lawmakers Chen Ting-fei and Lee Chun-yee of the opposition Democratic Progressive Party (DPP).

According to the report carried by the Liberty Times, a large number of chickens raised in a poultry farm in Tainan were confirmed by a government laboratory to have died from the H5N2 bird flu virus last month.

But the Council of Agriculture (COA) tried to conceal the information so as not to mar the launch of direct daily air and regular shipping and postal links on Dec. 15, the report alleged.

Legislator Chen voiced grave concern that Taiwan will be exposed to great risk if the COA fails to fulfill its duty now that direct transport links across the Taiwan Strait have been established.

As bird flu has also broken out in Hong Kong and China recently, the COA must quickly detect the origin of the H5N2 virus to help protect public health, Chen said.

Answering questions at the Legislative Yuan, COA chief Chen Wu-hsiung again denied that large numbers of chickens have died in Tainan County in recent months.

He also rejected allegations that the COA has attempted to hide information about a possible bird flu epidemic in southern Taiwan, stressing that the council will make public the results of its investigation once it is complete.

In response to media reports that bird flu had broken out in Tainan and Kaohsiung counties, COA officials said that a joint investigation by the COA and the Tainan County authorities has ruled out any cases in Tainan.

However, the officials admitted that at Luchu township in neighboring Kaohsiung County, some 400 chickens at a poultry farm had died in late October and that some others were found in November.

They noted that only around 3 percent of the chickens had died, a fatality rate that is within the normal range for chicken farms and far lower than the average mortality rate caused by the H5N2 virus.

Despite the fact that the chickens did not develop signs of respiratory disease -- a key symptom of an H5N2 epidemic -- animal health officials decided to cull all the remaining 18,000 chickens in an effort to prevent any adverse consequences.

The COA officials denied that they had tried to keep the situation secret, saying that a panel of 23 experts had still not completed an investigation into the deaths and that the delay had nothing to do with the opening of direct cross-Taiwan Strait transport links.