In a shift of thinking, governments in the EU and UK are now considering reversing the ban on vaccinating poultry against bird flu. This is in response to the largest avian flu epidemic so far observed in Europe, with 2,467 outbreaks in poultry recorded by the European Food Safety Authority (Efsa) in the 2021-2022 season, and an unprecedented number of highly pathogenic avian influenza (HPAI) virus variants detected.  

In the UK there were 56 outbreaks in poultry between June and September last year alone, prompting the Animal and Plant Health Agency (Apha) to begin actively testing a number of vaccine candidates in a bid to resolve the mismatch between the current H5N1 virus strain and the vaccines currently licenced.

First, the chicken
There is no market for vaccinated birds in the international poultry trade. Most governments are unconvinced that vaccination effectively controls the virus and maintain strictly controlled supply chains to ensure only healthy animals cross borders.

Vaccinated birds are also diagnostically difficult to distinguish from infected ones (a concept known as DIVA – differentiating infected from vaccinated animals), and so farmers, importers and exporters see no advantage in a vaccination programme that fails to remove risk from the virus and its fast-moving variants. With no demand, pharmaceutical companies have no incentive to invest in the development of effective bird flu vaccines, creating critical gaps in scientific knowledge of avian flu and outbreaks. 

This status quo was fine when H5N1 outbreaks were rare, and the need for large scale culling even rarer.

Next, the egg 
According to the World Organisation for Animal Health, bird flu  - and related culling - has killed 140 million poultry since October 2021, including 48 million birds in Europe and the UK combined, and just over 53 million in the US.  And because infected birds must be slaughtered and not vaccinated, egg supplies fall and prices surge.  In the US, a dozen eggs now cost more than a gallon of petrol, with egg prices soaring by 60% in the last year.

Why can’t it be fixed, COVID-19 style?
So why haven’t governments and big pharma put their heads together – as they did with COVID-19 – to work flat out and develop vaccines to control bird flu?  

Clearly there are multiple reasons for wanting to get avian flu under control, including damage limitation and business continuity for the poultry industry, as well as the cost of compensation and other expenses that governments shell out for the culling measures they mandate.

Animal welfare should not be ignored either.  Any extensive vaccination programme would have a high impact as it would require handling of large numbers of individual birds causing undue stress.  Mass culls and confinement of millions of birds every winter are also meeting increased public resistance as society seeks ways for humans, animals and the environment to co-exist harmoniously. 

The real challenge that must be overcome is trade restrictions, and that means implementing a new strategy with vaccination at its core for exporting countries.

Change is in the air, and it is being driven by industry bodies that represent both the chicken and the egg. The International Poultry Council and International Egg Commission recently issued a joint statement to try and convince the industry, international organisations and governments to allow vaccination while mitigating the risk of trade barriers.

Hoeford Research has its roots in the welfare of animals and vaccines for the poultry industry. We support vaccine development and vaccination programmes and believe they have a significant role to play in mitigating the damaging effect of avian influenza.