Letters to the Editor

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To the Editor:

When it comes to livestock health, countries can find themselves between a rock and a hard place. For an illness like avian flu, either they allow livestock producers to vaccinate their animals and risk trade restrictions as a result, or they choose not to vaccinate and leave their animals exposed to devastating outbreaks that can wipe out their entire flocks.

At the crux of this dilemma is the difficulty in distinguishing between animals that have been vaccinated and those that have been infected with disease. Both may show signs of antibodies, and many countries will not risk importing animals that could be infected.

In the long term, this is not much of a choice, as both options are unsustainable for animal health, economic viability and food security.

Bird flu, for instance, has led to the death and culling of more than 630 million birds in the last 20 years despite the existence of vaccines. The virus has now even spread beyond poultry to dairy cows and, in rare cases, people. The ripple effects extend beyond animal health, disrupting food supplies, damaging farm profitability, and posing risks to human health.

Brazilian producers are facing import bans from markets like EU (https://www.euronews.com/…) and China (https://www.ft.com/…) after reporting their first case of bird flu in 20 years this month. In Europe, foot and mouth disease (FMD) has recently led to trade border closures (https://www.foodnavigator.com/…) between some countries and significant financial losses running into the hundreds of millions.

Preventable animal diseases cause unnecessary damage to domestic and international food systems. But existing systems penalize countries that allow farmers to vaccinate their animals as part of disease control strategies.

TIME FOR A RETHINK

The recent losses and disruption caused by avian flu and FMD outbreaks should give pause for thought over how to strike a better balance for farmers, animals and consumers.

Vaccines are one of the most powerful tools for disease prevention alongside biosecurity and other measures and have been proven to effectively safeguard against animal disease outbreaks.

Vaccination against brucellosis, for example, has been shown to be highly effective in protecting cattle against this endemic disease. In India, brucellosis vaccination provides a 10-fold return on investment (https://www.researchgate.net/…) when comparing cost to benefit.

Yet, current trade policies carry the threat of export bans and other restrictions for producers who vaccinate their animals. Import policies that prevent the acceptance of vaccinated animals discourage countries from vaccinating livestock, which is leading to bigger outbreaks and more costly disruptions. In the U.S., bird flu has led to the culling of more than 40 million birds (https://www.avma.org/…), and in some European countries, FMD has racked up billions (https://www.gov.uk/….) in losses from its spread.

To break this downward spiral of animal disease and export barriers, countries need to consider more nuanced and adaptable approaches. If accepted by trading partners, more flexible strategies could allow countries to approach animal disease challenges on a case-by-case, outbreak-by-outbreak basis, using vaccination strategically so that it does not jeopardize trade and livelihoods.

Firstly, allowing differentiated strategies, such as vaccinating certain types of animals while maintaining trade in others, could curb disease outbreaks more effectively. In 2023, France demonstrated this approach by launching a nation-wide vaccination campaign for ducks against bird flu. This preventative action led to the country declaring itself bird flu free (https://www.reuters.com/….).

Secondly, expanding existing rules like regionalization (https://www.wto.org/…) could also enable vaccination as a localized response if agreed and recognized by importing countries. This would mean trade could continue from unaffected areas while specific regions use vaccination to curtail an outbreak.

Thirdly, countries should consider trade standards that enable and support continued vaccination of animals. At present, countries can achieve two different tiers of FMD-free status: with vaccination or without. Some countries strive for FMD-free status without the use of vaccination to open export markets but this leaves them vulnerable (https://www.woah.org/…) to future outbreaks.

Lastly, improving access to the latest vaccine technologies can give additional confidence that vaccination will not undermine trade and exports. Differentiation of Infected from Vaccinated Animals (DIVA) (https://www.epizone-eu.net/…) vaccines, for instance, allow for the distinction between natural infections and vaccine-induced infections. These marker vaccines induce an immune response that is different from the response induced by natural infections and can alleviate the likelihood of infected animals being indistinguishable from vaccinated animals.

Ultimately, governments must decide if vaccination occurs. Advancing these approaches will therefore only happen when countries sit down together, build trust, and agree on updated trade and animal health frameworks that reflect today's disease challenges and prevention tools. Collaboration is essential to ensure that disease control does not come at the cost of livelihoods or food security.

The Vaccination Forum held at the recent General Session of the World Organisation for Animal Health (WOAH) made it clear -- vaccines are one of our most powerful tools for meeting the growing challenge of animal disease. This recognition needs to now turn to action and agreement, uniting governments, industry, farmers, veterinarians and other stakeholders to reshape the approach to disease control, safeguarding food systems, public health, economies, and the environment.

Carel du Marchie Sarvaas,

Executive Director of HealthforAnimals

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