Biosecurity measures are being stepped up on poultry farms to protect flocks against avian influenza.
Wild birds in Cork, Limerick, Mayo and Monaghan have tested positive for bird flu since the beginning of November.
The Department of Agriculture says that bird flu is circulating in the wild bird population in Ireland, which poses a risk to poultry flocks all over the country.
Those keeping poultry have been requested to increase biosecurity measures to reduce the risk of spreading the virus. Increased additional biosecurity measures have been issued to farmers keeping flocks of more than 500 birds.
The H5N8 subtype of avian influenza has been responsible for outbreaks of disease in wild birds and poultry in a number of EU member states and the UK since late October.
Tens of thousands of turkeys will soon be slaughtered for Christmas and the threat of the virus is causing concern in the sector.
The advice to increase biosecurity applies to everyone keeping poultry. Warning signs of bird flu include a swollen head, discolouration of neck and throat, loss of appetite, respiratory distress, diarrhoea and fewer eggs laid. Experts say these symptoms vary between species of bird.
The Health Protection Surveillance Centre has confirmed that although the H5N8 subtype can cause serious disease in poultry and other birds, no human infections with this virus have been reported worldwide and it says that the risk to humans is considered to be very low.
Notwithstanding, members of the public are advised not to handle sick or dead wild birds. The public is also being advised to report any findings of sick or dead wild birds to Regional Veterinary Offices.
The Department of Agriculture also operates a special telephone line which will deal with any such reports, Tel: 1850 200456.