Two more farms in the Norfolk area of the UK are now under quarantine as the country battles a milder form of the avian influenza virus.
The spread of the virus in domestic poultry is bound to heighten public fears about the safety of poultry in the UK. Tesco, the UK's biggest retailer, has previously said its poultry sales fell five per cent when the first UK case was confirmed in the wild duck. Consumption of poultry meat has dropped by more than half in some EU states, with 300,000 tonnes now in storage across the bloc, according to EU estimates.
Over the weekend, the country's chief veterinary officer confirmed that tests have provided positive results for avian influenza, or bird flu, in chickens on two poultry farms near Dereham, Norfolk. The preliminary results indicate it is H7N3, a milder form of the highly pathogenic H5N1 virus.
The poultry flocks were kept outdoors. UK authorities have so far resisted calls to bring domestic poultry indoors for fear they may become infected with H5N1 via wild bird populations.
About 15,000 birds were being culled starting Sunday as the battle to stop the virus spreading intensified in the area. Earlier last week about 35,000 chickens were culled at a nearby farm after H7N3 was found in dead poultry. Authorities say the virus was probably transmitted to the other two farms through a breakdown in the quarantine restrictions.
The Health Protection Agency (HPA) also confirmed that a poultry worker at the first farm is suffering from conjunctivitis caused by H7N3 avian influenza.
H7 does not transmit easily from human to human. In almost all cases of human H7 infection to date, the virus, in both low and high pathogenic forms, has only caused a mild disease.
"Therefore at this stage this is a virus which only has extremely limited implications for human health," the HPA stated.
Last week Defra announced an increase control and precautionary measures against avian influenza. The decision followed an independent review in Octoer of the UK's avian quarantine system by a team chaired by Nigel Dimmock, a professor of virology at Warwick University.
Defra said 29 of the study's 32 recommendations have been accepted or accepted in principle. Two require further consideration and one has been rejected.
Last month the UK regulator responsible for testing for bird flu had to defend its methods today after scientific experts raised the possibility that they may be flawed.
Defra had to counter a report in New Scientist magazine, which quoted experts as questioning whether the low rates of milder forms of the disease found in the UK's wild birds indicated flawed testing methods. Defra says its methods and procedures are valid.
Scientists worldwide are worried that the H5N1 form of the virus, which can be transmitted from poultry to humans, may mutate so that it can be transmitted from human to human and start a influenza pandemic.
Since the beginning of the recent avian flu crisis, consumption of poultry and eggs has fallen dramatically in some member states, leading to a sharp reduction in prices. In some countries, such as Italy, demand has fallen by up to 70 per cent, drastically lowering poultry farmers' incomes.
The UN Food and Agriculture Organisation (FAO) reported that recent avian influenza outbreaks in Europe, the Middle East and Africa have caused dramatic swings in poultry consumption, increased trade bans and sharp price declines. The UN agency expects poultry consumption shocks this year in many countries.
"A steady erosion of previously expected gains in per caput poultry consumption will likely push down global poultry consumption in 2006, currently estimated at 81.8 million tonnes, nearly three million tonnes lower than the previous 2006 estimate of 84.6 million tonnes," stated FAO commodity specialist Nancy Morgan.
According to the FAO report consumption shocks are ranging from a dramatic 70 per cent decline in Italy in mid-February to 20 per cent in France and 10 per cent in northern Europe.
The crisis has also affected the $42 billion dollar feed sector in Europe, with demand losses estimated at up to 40 per cent in some countries, the FAO stated.
About 200 people have caught the disease and 113 have died worldwide since its onset in Asia in 2003, according to the World Health Organisation.