Bird Flu Is Threatening Chickens. Why Farmers Don’t Want a Vaccine.

Avian influenza, which swept the U.S. poultry industry in 2014 and 2015, is back. The current strain, known as H5N1, has ravaged US poultry houses since early last year, infecting more than 800 poultry flocks and wiping out about 60 million chickens and other birds (more than the previous round). about 10 million more). Infection).For American consumers, the impact is felt in the grocery aisle, with average egg prices More than double From the beginning of 2022.

From an industry perspective, the impact has been relatively contained, at least so far. The majority of the birds culled were owned by large privately owned commercial egg farms. Cal Main Foods (NYSE:CALM), the nation’s largest egg producer, said his farm was unaffected. (In fact, the company is having a great year, with quarterly earnings of $6.62 per diluted share in March, up from $0.81 in the same quarter last year. The rise is a contributing factor.) Chickens raised for meat, known as broilers, are largely spared.

Soaring egg prices and concerns about allowing the virus to spread from birds to humans in very rare cases have sparked debate about whether the United States should embrace an H5N1 poultry vaccination campaign. increase. At this point, such a move seems, at best, a thing of the past.apart from report In early March, the Biden administration was considering vaccination efforts, said a White House National Security Council spokesman. barons, “Today, we are focused on promoting and strengthening high-impact biosafety practices and procedures.”

But the full impact of H5N1 may already be unique to the US bird population, scientists say. This means that they respawn periodically. Once the virus takes hold and begins to rampage this spring, possibly affecting more birds, the pressure on vaccination could build rapidly. This could have significant implications for chicken and other avian producers, not to mention animal health actors who manufacture and distribute vaccines.

“Once we reach the epidemic stage, it makes a lot of sense to get vaccinated,” said Dr. Carol Cardona, professor of veterinary medicine and biomedicine at the University of Minnesota. “The realization that infections will recur, recur, and recur, makes the cost of treating each outbreak as an eradicable one less attractive.”

The move to vaccinate U.S. birds could face several hurdles, including the fact that most of the poultry industry is against it.Country exported $6 billion worth of poultry meat will be produced in 2022. Producers fear other countries will stop importing U.S. chicken over fears that vaccination will mask the infection.

These concerns come from experience. In 2014 and 2015, when his early H5N1 strain forced farmers to exterminate his 50 million birds, most of them turkeys and laying hens, more than 50 countries were killed in the United States. Impose trade restrictions on all poultry. According to one study, chicken exports fell by $1.1 billion in 2015. USDA reporteven though the virus almost completely escaped the broiler herd.

So far, the United States has been able to convince its trading partners not to impose sweeping bans of this kind during the current outbreak. (Some countries impose import restrictions at the county or state level.), but given that no other major poultry exporter has vaccinated their birds against H5N1, choosing that route will almost certainly result in a backlash from importers. .

Once governments have determined that some level of H5N1 vaccination is necessary, the next challenge is to protect birds from current strains of the virus. The USDA plans to begin trials of an avian flu vaccine this month, with first data available in May and full data from his two-dose challenge trial in June. A USDA spokesperson said the FDA will test four of his vaccine candidates. An official with animal health company Zoetis (ZTS) said one of them was his H5N1 vaccine, which the company developed in 2015. Details of the other three candidates have not been released.

If one or more of the vaccines are effective, a USDA spokesperson said the FDA will go through the process of finding and obtaining approval from manufacturers willing to manufacture them. This can take up to 3 years. it may be facilitated.

Zoetis said it is currently working to determine the efficacy of a vaccine being tested against the current strain by the USDA. Another Zoetis bird flu vaccine, targeting different strains, is in use in countries such as Egypt, Jordan and Iraq.

Outside the United States, Dutch scientists Said In mid-March, tests of Ceva’s avian flu vaccine and that of private German pharmaceutical company Boehringer Ingelheim found that both provided “100% protection against disease and mortality” in a small number of H5N1-infected laying hens. Did.

Ceva’s vaccine is not specific to H5N1 and targets all H5 viruses. John El-Attrache, Global Director of Scientific Research at Ceva, said: “Available.”

If U.S. authorities have settled on vaccines, the next question is which birds to vaccinate. Turkeys used for breeding are a strong option. They are particularly susceptible to viruses and their numbers are relatively low. Among chickens, laying hens are more likely to be targeted as they live longer and are more susceptible to infection than broilers.

Layers are usually vaccinated against other diseases as chicks. Campaigning for mature birds is a complex task, says Cardona. “Every time a person enters a barn, there is a risk. [of transmitting infection],” she says. That’s why, rather than vaccinating adult chickens, Cardona advocates vaccinating young chicks before they’re brought to an egg-laying facility. , it would take a process of two to three years to achieve a fully vaccinated general farm.

Another potential complication is that some bird flu vaccines, including Ceva, are made using live turkey herpes virus. The same backbone is used in other vaccines already given to many chickens, but each individual chicken can only receive one turkey herpes virus-based vaccine. If Ceva’s vaccine were administered to chickens in the United States, another vaccine would have to replace another.

For vaccine makers, H5N1 vaccination campaigns are unlikely to have a significant impact on their bottom line. “It’s the right thing to do, so we do it.”

Still, animal health companies are not ignoring this opportunity. In addition to Zoetis, Ceva, Boehringer Ingelheim,

Merck (MRK) also said its animal health division has a “large and ongoing research program” focused on bird flu.

So far, the issue of vaccination remains open. At a Senate hearing on March 16, USDA Commissioner Tom Vilsack told lawmakers not to expect an immediate answer. “We are a long way from having an effective vaccine, and we are very far from having a vaccine that the rest of the world will accept,” he said.

Scientists, however, will face a major test this spring when avian flu becomes a common epidemic.

Cardona said: “Looking at the situation, I think we should consider vaccination.”

Please contact Josh Nathan-Kazis at josh.nathan-kazis@barrons.com.