# 1545
The debate over the role of migratory birds in the spread of the bird flu virus continues.
This time it is the BNHS (Bombay Natural History Society) coming to the defense of the often maligned migratory bird. Unfortunately they give very little evidence of innocence other than `sick birds don't fly' line of reasoning, and instead demand `concrete evidence' before birds are blamed.
Sadly, the science on all of this isn't terribly good.
Testing methods aren't terribly reliable. We don't really know what percentage of healthy looking wild migratory birds, in places like India or China, carry the H5N1 virus. In many countries, dead birds - not healthy ones- are the focus of their testing programs.
Over the past year we've seen several media reports of asymptomatic, yet infected birds, coming out of Indonesia and Vietnam. But media reports are a poor substitute for good scientific investigation.
So we have two camps. Those that blame migratory birds, and those that believe it is the poultry trade and smuggling of birds that spreads the disease.
Actually, there is a third camp. The one to which I belong.
You see, I don't have a bird in this fight.
I see no reason why this should be a case of one or the other. I see migratory birds and the poultry trade as probably guilty of spreading the virus. Heresy, I know. Now I won't be invited to either side's conventions.
Oh, well.
The spread of the bird flu from district to district in West Bengal is almost certainly due to the poultry trade, while the Dorset Swans are a reminder that wild birds do carry the virus.
What we desperately need is more research to determine the relative contributions each side makes in the spread of this disease. Until then, much of what we hear is guess work and opinion.
Migratory birds not responsible: BNHS
Mumbai (PTI): Amid reports that the bird flu outbreak in West Bengal may have been caused by migratory birds, the Bombay Natural History Society on Sunday said it was very difficult for infected birds to fly hundreds of miles to spread the virus and they should not be held responsible without concrete evidence.
"One forgets that H5N1 virus causing Avian Influenza among birds is very powerful and crippling. No infected bird can survive and fly hundreds of miles and spread the virus in poultry fowl," Director BNHS and Principal Investigator of Avian Influenza project, Asad Rahmani told PTI.
Only four birds were found dead in a reservoir near Aurangabad. But the High Security Animal Disease Laboratory tested the samples of these birds H5N1 negative.
This is in contrast to 20,000 birds which were found dead near Kinghai lake in China, where the first case of Bird Flu was reported, Rahmani said.
BNHS is the largest non-government organisation (NGO) in the Indian sub-continent engaged in nature conservation research for past 125 years.
The state administration, however, has disagreed with the findings of BNHS and is not ready to give a clean chit to migratory birds.
"Birds carrying the virus need not be found dead. They can be carriers, spread the virus and go away scot free," Maharashtra Animal Husbandry Commissioner Ashish Sharma said from Pune.
