African Swine Fever Vaccine in Vietnam Nearing Global Approval, US Officials Say

The African swine fever vaccine being tested in Vietnam is close to approval, world and US veterinary officials have said.

Such a vaccine would be a major advance in combating the deadly disease that regularly ravages pig farms around the world, including in Romania, causing huge losses to the global pork market, estimated at $250 billion, in recent years .

After decades of failed attempts because of the complexity of the virus, two vaccines jointly developed by US scientists and tested in large pilot schemes by Vietnamese companies are showing “very promising” results, Gregorio Torres, head of the science department, told Reuters of the World Organization for Animal Health (WOAH), told Reuters in a telephone interview.

“We’ve never been this close to getting a vaccine that could work,” Torres said, noting that the two vaccines have “probably the best chance of succeeding” and being approved for sale worldwide.

Both vaccines have received approval in Vietnam for pilot commercial use, now completed. The next step, the first for an African swine fever vaccine and possible overseas sales, will be national authorization.

US Agriculture Secretary Thomas Vilsack said there may be interest in precautionary purchases in the United States, despite the country having been spared the virus so far.

“There will obviously be a specific interest,” Vilsack said in an interview with Reuters in April about possible Vietnamese vaccine purchases.

Vaccines could not be developed in the US because the virus is not present there, so it was decided to test them in Vietnam, where swine fever is a constant threat.

As of 2021, swine fever, which is not fatal to humans, has been reported in nearly 50 countries and has caused about 1.3 million pig deaths, WOAH said in a regular report last week.

The vaccine is ‘without safety concerns’

United States Department of Agriculture (USDA) researchers analyzed the results of one of the vaccines, NAVET-ASFVAC, which they developed together with Vietnamese company NAVETCO, a USDA spokesman said.

After the vaccine showed a high level of efficacy and no safety risks in trials, 600,000 doses were approved for initial sales to pig farmers in Vietnam, of which the first 40,000 “were delivered without safety concerns,” it said USDA.

That delivery followed a brief setback when the vaccine was suspended after dozens of pigs died last summer from inoculation on farms that, according to the USDA, used the vaccine off the label, administering it to pigs that were not supposed to. be inoculated, such as pregnant sows.

After resuming deliveries with proper veterinary monitoring, no such problems have occurred, the USDA said.

NAVET-ASFVAC is a live attenuated virus vaccine like those used in routine childhood vaccinations worldwide. The use of unlicensed live virus vaccines in China in recent years has raised concerns that they have caused the emergence of new strains of swine fever.

Only limited data are available from China’s trials of a live virus vaccine against swine fever.

The second vaccine tested in Vietnam, AVAC ASF LIVE, which was discovered by American researchers and marketed by the Vietnamese firm AVAC, has been delivered to more pigs than NAVET-ASFVAC in its pilot deployment, but the USDA said it has not yet reviewed the data.

NAVETCO, AVAC and Vietnam’s Ministry of Agriculture, which is responsible for approving veterinary vaccines, did not respond to requests for comment.