Email from Ruth Watkins, virologist, June 3 2007"....the period between purchase and slaughter was 7 to 24 of May so that is 17 days.
It reflects badly on farming that the man selling the birds has not come forward, but perhaps he was not a farmer.
I have seen people buying chickens out of cardboard boxes for instance at the Royal Welsh when a known poultry breeder is exhibiting and brings extra stock to sell. Of course who they were would be known.
I think the authroities have behaved well over this H7N2 outbreak, the measures taken were proportionate. It always takes a little longer to get a negative result as on the second holding that had a connection with the market, as culture would be done as well as RT-PCR.
I hope the investigation of the small flock at the infected holding was thorough as they might be able ot answer the question of whether the virus was already present there or not. It is possible that influenza viruses from wild birds infect small free range flocks, the infected birds do not become noticeably ill and the infection dies out coming to a dead end in the small flock. One would never know of its presence unless susceptible birds that developed disease were brought in - the Rhode Island Reds could have been in fairly poor condition and have been more susceptible to disease with the low pathogenicity influenza virus (rather reminiscent of Norfolk when it was the intensively reared birds that became ill not the free range flock)
As far as I can gather it is the brought in birds that were unwell and not the resident birds on the small holding.
It is interesting that the man who sold the chickens from the back of a van has not come forward. It means they will make more laws in regard to poultry I expect. In fact though the initial Rhode Island Red died one day after purchase, I wonder if one can be sure it was H7N2 unless she could be exhumed and tested.
It may just be that the Rhode Island reds were susceptible to illness with tthe low pathogenicity virus infecting the more robust free range birds already on the small holding.
It may be the infection passed from a wild perhaps water bird to a bird, in Wales, as H7N2 would be present occasionally in wild birds.
I am not sure whether the investigaton of the small holding flock could reveal this because sufficient time passed for infection to spread to the other birds who could also make antibody in the time of 10 days or so.
I wonder indeed if they were all sampled before they were killed.
Again perhaps the Rhode Island Reds were parked next to water fowl at the market or carried in crates that had held wild birds or water fowl. There are a number of possibilities.
I expect the man at the market has killed and burnt the evidence of infection otherwise why has he not come forward?
Did he have any ill birds?
Who are the poeple in NW England who have had the infection, did they visit the small holding?
I presume the two documented cases in Wales had had contact with the birds on the small holding.
H7 flu viruses are known to give rise to eye infections in humans infected by birds and for there to be limited spread to household or close contacts."
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