# 4316
Poultry vaccination against the H5N1 bird flu virus has been the subject of considerable debate over the years, with many scientists warning that the the overuse of vaccines could backfire.
Vaccination, it is feared, could hide the infection and allow it to silently spread, and may actually drive the evolution of the virus.
For developing countries with poverty and food insecurity issues, however, vaccination is often considered preferable to wholesale culling.
Today Emmy Fitri and Dessy Sagita, writing for the Jakarta Globe, bring us the first English language coverage of a story that has been showing up on the flu forums for a couple of days now.
The declaration by a researcher in Indonesia that the H5N1 virus is changing, and vaccines are losing their effectiveness. Until now, we’ve only had machine translations from Bahasan, so this version posted by Shiloh on FluTrackers is particularly welcomed.
This, of course, isn’t the first time we’ve heard this.
Leading scientists such as Zhong Nanshan of China, have stated,"The existing vaccines can only reduce the amount of virus, rather than totally inactivating it.”
Dr. C.A. Nidom, whose name has appeared often in this blog, was quoted in Poultry Indonesia as saying:
Poultry Indonesia Printing Edition, March 2009
(excerpts)
Chairul Anwar Nidom, a virologist with the Tropical Disease Centre at Airlangga University in Surabaya, said a common policy on bird flu was lacking among government agencies, making controlling the disease more difficult.
Nidom criticized the government’s policy of vaccinating poultry rather than culling, believing that it masks the virus, and ultimately contributes to its mutation.
The OIE (World Organization For Animal Health) reaffirmed their long-standing position that vaccination of poultry cannot be considered a long-term solution to combating the avian flu virus.
In Avian influenza and vaccination: what is the scientific recommendation?, the OIE reiterates their strong recommendation that humane culling be employed to control avian influenza, and advising that vaccines should only be used as a temporary measure.
While the OIE concedes that some nations may require the use of vaccines for `several years', they strongly urge that countries move away from that program and towards the more conventional culling policy.
I’ll not attempt to post more than the opening paragraphs. So follow the link to read it in its entirety.
Emmy Fitri & Dessy Sagita
A researcher inspecting samples in the lab. Recent studies are seeing genetic changes between H5N1 virus samples taken in 2003 and samples taken in the last two years. The virus of 2003, from Banten, is still be used as vaccine seed in most current vaccination products and fears have been raised they may no longer be effective against the mutated virus. (AP Photo)
Mutated H5N1 Virus Raises Doubts About the Effectiveness of Flu Vaccines
A genetically mutated avian flu virus is believed to be behind a string of deadly outbreaks in bird populations over the past two years, a scientist said on Tuesday, warning that the new virus had the potential to be more lethal than its ancestor should it infect humans.
Virologist I Gusti Ngurah Mahardhika said the government’s vaccination program with a large number of poultry farms in the past few years may backfire because the mutation was partly suspected to have been caused by an outdated vaccine.
“I have strong evidence that the old vaccine seed [already developed by the country’s vaccine makers] cannot stop the new virus,” said Mahardhika, who is also head of the Biomedical and Molecular Biology Laboratory at the Udayana University’s Veterinary Medicine School.
He said isolated virus samples taken from already vaccinated farms in Java, Sumatra, Bali and Sulawesi from 2008 to 2009 were compared with samples from their ancestor H5N1 virus taken from Legok, Banten, in 2003.
“From the study, we found genetic differences of up to 8.7 percent from the ancestor virus,” he said.
Related Post:
Widget by [ Iptek-4u ]