By Emma Jane Kirby
The go ahead has been given to vaccinate Dutch poultry
The Netherlands is Europe's second largest poultry producer and no stranger to the impact of bird flu.
In 2003, an outbreak of a vicious strain of the disease, H7, killed thousands of chickens and resulted in the slaughter of around 31 million birds, ruining many farmers.
This time the country is taking no chances.
Despite the fact that the Netherlands has not recorded a single case of the H5N1 virus, the Dutch government has received permission from the EU to vaccinate its free range birds and back yard poultry.
The vaccination is voluntary, and must be paid for by participating farmers.
Jaap Von Dalen is one of the farmers who must make up his mind in the next couple of weeks whether he wants to vaccinate.
Jaap Von Dalen says his free range birds do not like being kept inside
He has 12,000 free range, organic chickens on his farm in Barneveld in central Holland.
The birds used to roam the fields freely, but now the government has ordered all birds to be kept inside unless they are vaccinated, fearing they may come into contact with infected wild birds and spread the virus.
Jaap lost all his birds to the 2003 outbreak of bird flu and would like to protect his new flock, but knows that vaccination carries other risks.
"I want to vaccinate because I know what bird flu can do - after the last outbreak I didn't even want to be a farmer anymore. I started again, built up a new flock and now I export my eggs to Germany," he said.
"But I'm worried the Germans won't want to buy produce from chickens which have been vaccinated, and if I can't sell my goods then I'll be broke."
France has already seen the negative effect of vaccinating birds - several countries have refused to accept imports of French poultry meat after farmers in Landes were given permission to vaccinate geese and ducks.
Critics of vaccination warn that current bird flu vaccines do not offer complete protection from infection and could, in some circumstances, "hide" the virus in affected flocks.
But many farmers' associations and vets feel vaccination unfairly stigmatises, and are calling for an EU-wide vaccination policy.
Klaus Osinga from the LTO, the Dutch Farmers Association, speaks for many in the Netherlands.
"It doesn't make sense for some countries to vaccinate but for other EU countries like the UK not to. It's a political and an economic decision. Perhaps it's time to think more about animal health and about stopping the spread of bird flu," he said.
Leading virologists such as Albert Osterhaus, the man who first proved that humans could be infected by avian flu, agrees.
"Bird flu is a serious threat to us all but we don't spend enough money on fighting it. The whole world needs to pull together if we are to fight it effectively," he said.
"After 9/11, we spent billions of dollars on combating the threat of bio-terrorism. OK, but let's not forget that the main bio-terrorist is Nature itself. Remember HIV/Aids? Remember Sars? Well bird flu is knocking on our door."
Catch 22 situation
Back on his farm, Jaap is still unsure if he will vaccinate. His birds are currently huddled in sheds - 3,000 crowded into a single barn.
"They don't like being inside," he says. "Their whole lives they have been free and now they are locked in. My friend says his chickens have become very stressed and aggressive - 400 have pecked each other to death."
So, should Jaap vaccinate his flock, set them free and risk dire economic consequences, or should he leave the chickens inside, reassured by the knowledge they cannot mix with infected wild birds and catch the virus? It is a Catch 22.
Jaap's business thrives at present partly because his products carry the "free range" stamp - but if he keeps the birds inside, he knows he will probably lose that valuable label.