According to officials in Taiwan they have found a highly pathogenic strain of avian flu, H7N3, in droppings left by a migratory bird.
The agriculture department there is apparently carrying out tests to see if the virus has spread to nearby poultry farms.
It seems that just like the deadly H5N1 strain of bird flu, which has killed more than 60 people around Asia, the H7N3 strain can also infect humans.
Huang Kwo-ching, director of the animal health inspection division at the Council of Agriculture, says they are very concerned about the H5 and H7, as they can both infect people and birds.
They are apparently carrying out tests at poultry farms within a 3 km radius of the area.
A single sample of H7N3 was found in marsh land in the southern city of Tainan but no dead birds were found in the area.
This is the second time the strain has been detected in Taiwan, the first case of H7N3 was discovered in the outskirts of Taipei in April.
According to the World Health Organisation (WHO) and World Organization for Animal Health, H7N3, which can potentially be transmitted to humans, was first detected in turkeys in Britain in 1963 and made one of its last known appearances in poultry in Canada in April and May 2004.
WHO says that the H5 and H7 viruses are the only avian influenza subtypes that are implicated in outbreaks of highly pathogenic disease, and is recommending aggressive control measures, which includes the culling of infected and exposed poultry, for the two subtypes, even when the virus initially shows low pathogenicity.
To date Taiwan has not experienced a major outbreak of H5N1, but last month, the island found its second case of the deadly strain since 2003, in birds smuggled in a container ship from China.
An outbreak of the lesser H5N2 strain of bird flu in Taiwan in 2004 led to the culling of hundreds of thousands of fowl.