New bird flu strain poses serious threat
The ministries of Agriculture and Rural Development and Health have warned of a possible large-scale outbreak of bird flu in the near future. Viet Nam News reporters Thu Hien and Thanh Hai talked to experts about the main causes of the disease's resurgence and prompt measures to prevent its spread.
What is the main reason for the resurgence of bird flu at this moment?
Dr. Santanu K. Bandyopadhyay, Team Leader Avian Influenza Programme, Food and Agriculture Organisation of the United Nations (FAO) in Viet Nam
In northern Viet Nam and parts of central Viet Nam, we have seen the emergence of a new strain of the bird flu virus since the beginning of 2011. This particular virus is not adequately protected by the currently available vaccines for poultry. Due to the complexity of this virus strain, the government has halted the mass vaccination of poultry since the summer of last year. So there is now a large number of vulnerable poultry populations not immune to the disease. Therefore, a disease outbreak in such a nave population will spread fast and involve huge losses to the poultry.
|Dr. Santanu K. Bandyopadhyay
Based on the official reports of the outbreaks in poultry that we have now, I don't immediately perceive the risk of large scale outbreaks as any greater than this time last year or the year before that. The number of outbreaks reported in poultry in the last one month is within the average of the last three years.
However, due to the reduction in vaccination coverage and the emergence of the new virus strain in the North, there is going to be greater risk period ahead.
Ph.D Nguyen Van Cam, deputy director of the Ministry of Agriculture and Rural Development's Centre for Veterinary Public Health
The large-scale outbreak of bird flu with as terrible effects as in 2003-04 will not happen. However, this disease will have a scattered outbreak in some localities.
|Ph.D Nguyen Van Cam
The resurgence of this disease is the result of unfavourable weather conditions weakening the resistance of poultry and the poultry production system of small-farm oriented and free-grazing ducks failing to adopt appropriate bio-security measures. We have to get used to living with this disease.
It is not right to assume that stopping mass vaccination nationwide is the main cause of the disease's outbreak. Thailand has already stopped vaccinations but the disease did not resurge. Vaccinations are just a technical method to reduce the possibility of the outbreak of bird flu, not totally eradicate the disease.
No country has sustained a mass vaccination programme in poultry for a long time. After an emergency situation has been controlled with vaccinations, a strategic exit-plan has to be applied in which vaccinations are gradually withdrawn.
Dr. Graham Harrison, Acting WHO Representative
Viet Nam is considered to be endemically infected with H5N1, with outbreaks detected in poultry in a number of provinces across the country in 2011. Therefore this is not a resurgence of the disease. H5N1 viruses will likely continue to persist and be a concern for Viet Nam and more widely, pose a threat to the poultry industries and remain a potential source of pandemic human influenza. It should be recognised that influenza viruses continuously evolve through mutation and re-assortments; this is a natural process that requires on-going monitoring.
Prof. Nguyen Tran Hien, Director of the National Institute of Hygiene and Epidemiology:
The Ministry of Agriculture and Rural Development reports that 5 per cent of ducks were infected with H5N1 virus. It proves that the virus still exists in the environment and could cause outbreaks.
There is a high risk of H5N1 virus transmission from animals to humans. The biggest problem is that many people have not been fully aware about the risk of disease after a long time of no infected cases in humans. They did not implement any regular preventive measures. In the coming time, we forecast that bird flu in poultry could break out in many provinces and bird flu in humans will also occur scatteredly.
Is it farmers that should be blamed for the spread of the disease?
Cam: No, it's not their fault for the spread of bird flu. If we wish to raise their awareness of the disease in a timely way, we should first publish and implement the supporting policies to assist them in case their poultry is contaminated.
The Prime Minister released Decision No.719/QD-TTG in 2008 supporting policies including financial assistance to poultry farmers. However, how long until this assistance reaches farmers? How much? It all depends on local authorities. So far, many affected farmers have been waiting for the assistance for their killed poultry.
So when farmers find that they may lose their flocks of poultry, their most precious assets, they will have to find a way to lessen their losses by selling them off.
Bandyopadhyay: We cannot entirely blame them when they don't want to bring signs of any sickness in their poultry to the attention of the authorities. It is necessary for the Government to give a supporting hand to them when trying to encourage them to promptly report any signs of infection.
Which short and long-term measures should Viet Nam take to cope with this disease?
Harrison: Control measures must continue to focus on reducing the transmission of the virus – both to other poultry and to people. Key transmission pathways for this virus are bird to bird, farm to farm, or market to farm. Also spreading happens through contaminated materials and equipment such as manure, feathers, vehicles and soiled clothing. In order to reduce the threat of H5N1 infections, transmission pathways of the infection will have to be broken. This is evidently possible through certain tactical changes with the poultry production system adopting safe production practices. These changes must be made on the farm, by traders, at markets, slaughterhouses and by backyard poultry farmers. The Ministry of Health has been investing in new facilities, training staff, increasing surveillance, promoting behaviour changes and providing health education for the general public, the media, poultry producers and regulators.
|Dr. Graham Harrison
Bandyopadhyay: This disease should be thoroughly and promptly investigated and responded to. Eliminating the affected poultry and vaccinating the unaffected ones are two emergency solutions. Animal health workers and poultry farmers are encouraged to report any sign of sickness in poultry to the nearest veterinary centre. Warnings and awareness campaigns should be launched particularly during the high risk periods targeting the poultry producers and others involved in the poultry trade to follow basic safety in production and handling practices.
In the long-term, both the disease management and the poultry production management need to be improved.
There is a need for investments in improving the veterinary service delivery system, particularly in the rural areas so that the poultry farmers are adequately advised on appropriate care, vaccination and bio-security methods in farms. Investments will be required in surveillance for the disease rather than waiting for these to be brought to the notice of the authorities. The farmers have to be encouraged to report any sickness in their flock rather than try to sell off or eat sick birds themselves.
For poultry production, risks at farms, slaughtering, transport and market points will have to be analysed at provincial, regional and national levels and appropriate measures taken to mitigate the risks at each point. Good production practices through the development of small-scale business plans, which are economically viable and appropriate for adoption of bio-security measures, will have to be made popular.
Investments will also be needed for further improvement of laboratory diagnostic facilities and in research for development of effective vaccines.
This week (Feb 14-16), FAO, WHO and OIE will join national experts and selected field officers in Viet Nam to address gaps in surveillance and control of both human and animal avian influenza. They will work to improve workings between animal and public health sectors to reduce the burden of human and poultry disease and rapidly detect and respond to the emergence of potentially human-infectious strains.
Cam: Viet Nam has yet to be successful in producing its own vaccine because H5N1 virus continuously evolves through mutation and re-assortments. It forms its new strains during the process of researching, experimenting and creating a vaccine, which in Viet Nam takes several years. So, I put forward two long-term solutions.
First, the country needs to build a system of local animal health workers who take responsibility for detecting and reporting signs of sickness in poultry to the higher authorities to immediately respond. Because farmers fear having their poultry killed and local authorities fear losing their positions the current situation of infected poultry is prolonged.
Second, appropriate bio-security measures should be applied to poultry production in the country.
What should people do to protect themselves?
Hien: Both of the two fatal cases resulted from too late hospitalisation and treatment. So, it is important to early detect and treat patients. People are absolutely not allowed to slaughter and eat ill poultry. Personal hygiene and food safety measures should also be followed. People, who have a high fever and are in proximity to sick poultry need to come to the medical unit for examination and treatment.
|Prof. Nguyen Tran Hien
Harrison: It is very important that the general public always take simple precautions to reduce exposure to the H5N1 virus. These include extra vigilance in cases of sudden disease and death in poultry, immediate reporting of the disease to authorities and good hygiene practices while handling, slaughtering and preparing poultry for consumption. — VNS