Martin W

Item in yesterday’s South China Morning Post on vaccination of poultry in Guangdong province, quoting Yu Yedong, provincial animal inspection and quarantine inspection head.

– 94% of Guangdong’s chicken population vaccinated; but shortage of vaccines meant some birds only given one shot, so may still be vulnerable to H5N1. (Best protection after booster shots given, 3-4 weeks after first ones given to 14-day old chicks.) Big farms all give two shots.
A veterinary expert said two shots ok for chickens maturing in summer; three better for winter maturing birds.
– Guangdong allocated several million doses of H5N1 and H5N2 vaccines a day.
– Flocks for export to other than Hong Kong are not vaccinated, as some countries say that if detect antibodies they can’t tell if due to vaccines or they’re sick birds.
“But Mr Yu said the administration’s own tests found that the virus was so potent that no chickens survived infection.”
(Much as seems typical with infected wild birds; maybe

Today’s SCMP has item with Guan Yi quoted as saying vaccinating China’s billions of poultry is impossible. Notes re no of months needed even if great many people (soldiers) vaccinating birds each day; and once done, have to start again as more chickens reared.

Echoes concerns in recent news item quoting US poultry disease experts:
China bird vaccination crews could spread virus
Teams might carry germ farm to farm

In this:

China’s plans to vaccinate billions of chickens against avian flu could backfire and end up spreading the disease, poultry and vaccine experts warn.

Vaccination teams can easily carry the virus from farm to farm on their shoes, clothes and equipment unless they change or sterilize them each time, the experts said. That could be particularly difficult in China, where the veterinary care system is underfinanced and millions of birds are kept in small flocks by families.

Also, experts said, the task is likely to be overwhelming because the Chinese eat about 14 billion chickens a year, so mass vaccinations would have to be repeated again and again, while the risk of the disease being reintroduced by migratory birds, in which it is now endemic, would be constant. [Note: seems there’s no real evidence for this assertion; I’ve emailed Carol Cardona about it, but nothing solid in reply – chiefly based on work with domestic ducks; ignoring, say, 74,000 apparently healthy wild birds tested, only one positive result – faecal sample from Mongolia]

Bird vaccination campaigns involve a huge amount of labor because the animals must be injected one by one. China’s Agriculture Ministry said Tuesday that it would inject all of the nation’s 5.2 billion chickens, geese and ducks with a vaccine.

Dr. Leon Russell, president of the World Veterinary Association, said that an official from Vietnam told him recently that Vietnam had despaired of ever vaccinating all its birds because it would need 100,000 more trained vaccinators.

“So, for the life of me, I can’t figure out how China will vaccinate billions of chickens,” he said.

Post edited by: martin, at: 2005/12/03 10:04