EU veterinary experts are to consider for a second day whether to approve plans by France and the Netherlands to vaccinate part of their poultry population as a precaution against the spread of bird flu.
The meeting in Brussels comes as Slovakia confirmed it had become the latest EU state to test positive for the virus, although further scientific tests are needed to confirm if it is the deadly H5N1 strain.
The European Commission said yesterday there were "positive discussions" among its committee of experts on the vaccination plans put forward by the EU's biggest poultry producers, France and the Netherlands.
But member states remain divided over whether vaccination can stop the rapid spread of bird flu across Europe and its likely impact on poultry exports to third countries.
Some experts and officials are worried that vaccination might not be effective in preventing the virus, as birds not fully immunised may mask its spread. Immunising millions of birds will also be difficult as each bird must be inoculated a number of times.
EU health commissioner Markos Kyprianou said the vaccinations were not fully effective and would still require extensive surveillance of birds.
Minister for Agriculture Mary Coughlan said after a meeting of EU agriculture ministers on Monday that she would not be in favour of vaccinating the Irish commercial poultry population.
However, a committee of Irish experts will meet today to discuss a series of preventive measures, which include the possibility of vaccination.
France has submitted plans to the commission to vaccinate 900,000 ducks and geese in the regions of Landes, Loire-Atlantique and Vendée, which are considered to be areas at high risk of avian influenza.
The Netherlands wants to vaccinate all free-range hens and poultry kept on small holdings throughout the country. The vaccination would be provided on a voluntary basis, as an alternative to the requirement that birds be kept indoors.
Some experts believe vaccination could be the right course of action for a small, densely populated country such as the Netherlands.
In 2003 it faced an outbreak of a different type of bird flu, which resulted in the slaughter of 30 million birds, a third of the national flock.
But the EU is split on the merits of preventive vaccination, particularly since it can damage export trade if a country's meat products are blocked by its usual importers.