Over last winter and spring the United States saw just over 200 outbreaks of HPAI H5 in commercial poultry operations, while at the same time the island nation of Taiwan reported nearly 1,000 outbreaks (of H5N2, H5N3 & H5N8).
Although North America suffered bigger overall losses, due to much bigger farms being hit, Taiwan’s poultry industry has been badly battered. And unlike in the United States, Taiwan’s bird flu miseries have persisted over the summer.
In neighboring mainland China, H5N2 has been a perennial problem, and until this year the H5N2 strains showing up in Taiwan have closely matched the Chinese strains. In January, however, three new HPAI H5 viruses appeared in Taiwan – all apparently related to the H5N8 virus which first erupted in South Korea 12 months earlier.
From the OIE Notification On Taiwan’s `New’ HPAI H5N2:.
The homology of H5 between the isolates from these infected farms and the South Korea 2014 H5N8 strain is near 99%. The homology of N2 between the isolates from these infected farms and the China 2011 H5N2 strain is 96%. This H5N2 strain is obviously novel to Taiwan.
Shortly after arriving - likely carried in by migratory birds - the H5N8 virus reassorted with local avian influenza viruses and produced new versions of H5N2, and an H5N3 reassortant. The old H5N2 remains in circulation, but has now been joined by the `new’ H5N2 strain, H5N8, and a novel H5N3.
Faced with mounting losses, and another fall bird flu spike to deal with, local poultry owners are getting desperate, and some have apparently been lobbying for (or perhaps, even illegally importing) AI vaccines.
Unlike China - which liberally uses AI vaccines - Taiwan (and much of the rest of the world) have avoided their use, and for some very good reasons:
- First, China, Egypt, and Indonesia – the three biggest consumers of HPAI poultry vaccines (cite Impact of vaccines and vaccination on global control of avian influenza by David Swayne) – are just as firmly entrenched with bird flu today as they were a decade ago when the decision was made to use them.
- Worse, the diversity of HPAI flu viruses has grown markedly while using AI vaccines, a phenomenon we explored last month in PLoS Bio: Imperfect Poultry Vaccines, Unintended Results and last April in New Scientist: The Downsides To Using HPAI Poultry Vaccines.
- In last November’s EID Journal: Subclinical HPAI In Vaccinated Poultry – China researchers found evidence to suggest that `imperfect’ vaccines were driving the evolution of new clades, and and the creation of subtypes, while last February, in Recombinant H5N2 Avian Influenza Virus Strains In Vaccinated Chickens – its authors reaffirmed that `AIVs can continue genetic evolution under vaccination pressure’.
Even though the United States has authorized the production of an AI vaccine (see USDA Adds HPAI H5 Vaccine To National Veterinary Stockpile), the decision to deploy them is far from a foregone conclusion. The USDA stresses:
`Any decision to use vaccination in a future HPAI outbreak would require careful consideration of the efficacy of the vaccine, any impacts of using HPAI vaccine in the field, and the potential trade impacts.’
Which brings us to a long report (translated from Chinese) from Focus Taiwan, that announces something we’ve known for some time, that the `new’ H5N2 virus in Taiwan is related to the Korean H5N8 strain, not the Chinese H5N2 virus.
They further advise that the existing Chinese AI vaccine would likely be ineffective against these new reassortants, and could possibly make their situation worse.
While not completely ruling out the future use of an AI vaccine, the COA reiterates that AI vaccines are prohibited in Taiwan, and there are currently no plans to introduce them. They then warn of severe penalties for the illicit manufacture, import, processing, trafficking and use of any illegal animal drugs.
Press time: 2015/10/23 13:01 the latest updates: 2015/10/23 13:01
(,, Chen Zhengwei Taipei 23rd) media have questioned Taiwan new types of influenza virus in poultry, associated with the County of South China Agricultural University H5N2-D7 flu vaccine? Plant and animal epidemic prevention and Quarantine Bureau stressed today that the Council of agriculture, which is not the same source.
Prevention and Quarantine Bureau said today that the contact the COA animal health Research Institute shows, new case of bird flu in China belong to 18.104.22.168 branch, H5N2-D7 influenza vaccine virus strains differ from the Chinese mainland 2.3.2 branches, not belong to the same source.
Anti-check Council explained, view this China found of new H5N2, and new H5N3 and the H5N8 avian influenza virus of H5 gene sequence, found its each other between similar degrees up 99.3% above, and 2014 Korea BA duck H5N8 avian influenza virus of H5 similar degrees up 98.8% above, and the, virus was check out time quite close, evidence displayed this three strains virus is may is by with a migratory birds carry to Taiwan.
Prevention and Quarantine Bureau said the international highly pathogenic avian influenza (HPAI) prevention and treatment experience, recognize culling biosecurity strategy to their early reporting and fortify software and hardware, for the most direct and effective way to prevent and fight against HPAI.
Because of the bird flu virus is changing and restructuring property, prevention and Quarantine Bureau believes that if you desire to use vaccines to protect the effects, to be considered between vaccine strains and wild type changes, and vaccine administration of coverage needed up to a certain percentage, can be effective.
Moreover, the use of poultry after the vaccine to produce antibodies, can also cause viral recombination and mutation pressure and immune poultry still infected Detox as the stealth Communicator, experts do not recommend the use of the vaccine.
Prevention and Quarantine Bureau pointed out that, because the international community regarding the use of bird flu vaccine for poultry meat products banned imports, and most of the countries in conditions of the vaccine is not used culling policy has been successful controlling HPAI outbreaks.
Conversely, some States making use of the vaccine is still ongoing, so, at present, China still prohibits given bird flu vaccine nor planning to universal immunization for the prevention and control of avian influenza outbreaks.
Anti-check Council reiterated, illegal manufacturing, and entered, and processing, and trafficking and the using illegal animal with drug is violations, for maintenance animal health, animal with drug management method Yu 102 years January 23 amendment announced, sharply improve pseudo, and ban drug related trafficking and the using penalty is, reminded livestock households do not using unknown, and without approved of animal with drug for control animal disease or regulation physiological function, for seized illegal user, law can at NT 60,000 yuan above 300,000 yuan following penalty fines; 1 years within again who, Fines of between NT $ 500,000 more than 2.5 million Yuan.
Prevention and quarantine Administration said will continue to strengthen border inspection recorded 103 to 104 years expiring on September 30, quarantine of incoming passengers breaches bring administrative fine cases of 1610.
Prevention and Quarantine Bureau further said that 103 to 104 years expiring on September 30, express cargo and general cargo do not follow regulations to apply administrative fines amounted to 315 of animal and plant quarantine, and called on people not to purchase or your network to freight entering, to bring their own, express freight and parcel delivery of veterinary medicines to avoid offence to be punished. 1041023