Nurul Islam Hasibbdnews24.com senior correspondent
Dhaka, June 4 (bdnews24.com) – The government's move to vaccinate poultry against frequently changing avian influenza virus has 'surprised' experts because globally it is recommended not to use it for public health's sake.
Experts say the available vaccines in the world have been able to reduce poultry fatalities for some time, but the vaccinated birds' capabilities to transmit the disease 'silently' after being infected caused 'massive' human mortalities.
Indonesia, Egypt and Vietnam had been vaccinating poultries but stopped after an influx of human fatalities last year followed when the virus also changed its strain.
Fisheries and Livestock Minister Abdul Latif Biswas on Sunday told journalists that considering poultry farmers' 'long-standing demand' the government planned to 'experimentally' introduce the vaccine.
He said a committee had been formed to finalise the decision to that end.
The Food and Agriculture Organisation (FAO) and the World Health Organisation (WHO) experts say they are 'surprised' by the move.
Mat Yamage, Chief Technical Adviser to the FAO Avian Influenza Control Programme, told bdnews24.com that earlier they 'warned' the government against using vaccines.
He said the situation where the vaccine once used was 'serious' and that 'there is no record of successfully controlling H5N1 with vaccines'.
"We would strongly say it should be discussed with technical experts."
Globally, it is recommended that poultry farms maintain bio-security to prevent the virus and government have measures for early reporting, rapid action, culling and surveillance to control avian influenza outbreaks.
Yamage said once vaccinated, birds would not show the flu symptoms early.
"It means the detection would be very difficult. But we need to detect it as early as possible to contain its spread."
According to him, many people died even after Indonesia, Egypt and Vietnam –top three avian influenza-burdened countries – started vaccinating poultry.
"It's because of silent infection," he said, "finally they had to stop vaccination." The FAO expert said they had a meeting recently with Indonesia, Egypt and Vietnam and discussed the problems. "They are concerned about how to get rid of their problems."
He said bio-security was the most important measures to control avian influenza, but Bangladesh was not practising it.
Last year Bangladesh witnessed 171 bird flu outbreaks in poultry. This year so far it recorded 21 outbreaks but Yamage said it did not mean the situation improved.
"We found sick birds in the market. Trucks were found at check points carrying sick birds.
"It means outbreaks are happening but remain under-reported."
Prof Mahmudur Rahman, Director at the Institute of Epidemiology, Disease Control and Research (IEDCR), told bdnews24.com that during last month's conference in Ho Chi Minh City, Vietnam's experts told them 'not to start vaccination.'
He said as four flu viruses –H1N1, H5N1, H3N2 and H9N2— was circulating in Bangladesh, silent infections might be 'devastating'.
"Once (the four viruses) reasserted themselves, it will be a big threat."
WHO influenza expert Dr ASM Alamgir said they never recommended a country to vaccinate its poultry against H5N1.
"It's not the way to combat H5N1," he said, 'the virus is changing.'
"Even in Bangladesh the present clade 2.3.2.1 is new. It was detected last year. Since 2007 clade 2.2 was circulating in Bangladesh."
He said there is no vaccine in the world for the clade that currently circulates in Bangladesh. Coordinator of One Health Bangladesh Nitish Chandra Debnath said the vaccine would not be 'effective' in Bangladesh.
"The virus has already changed its strain," he said, and "it will continue to change." "If it (the vaccine) is effective, then why would we oppose it?"
He said the vaccine was not working but creating problems instead and added that it should be technically evaluated.
The government has confirmed six human infections after the first case of H5N1 influenza was detected on May 22, 2008.
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