African Swine Fever Vaccines Co-Developed by USDA Approved for Commercial Use in Pigs in Vietnam

Vietnam’s Ministry of Agriculture and Rural Development has approved commercial use of the first two African swine fever vaccines for pigs. The first vaccine is known as NAVET-ASFVAC, co-developed by Navetco Central Veterinary Medicine in Vietnam and United States Department of Agriculture’s (USDA) Agricultural Research Service (ARS) and the second is called AVAC ASF LIVE, developed by AVAC Vietnam.¹

African swine fever is a highly contagious viral disease affecting both domestic and feral swine. The virus is spread through contact with infected animals’ bodily fluid.² This disease is not a threat to human health and cannot be transmitted from pigs to humans but it has had a significant impact on food security, biodiversity, and economic security for farming communities.³ African swine fever has never been detected in pigs in the U.S.⁴

According to Vietnam’s General Statistics Office (GSO), 86,000 pigs were culled or died as a result of an African swine fever outbreak in 2020. The African swine fever epidemic caused a decline in pork production and an unprecedented increase in pork prices necessitating the importation of live hogs, pork and pork products. The GSO reported that as of April 2021, there have been sporadic small-scale outbreaks reported in 22 localities in Vietnam resulting in the death and culling of an additional 5,000 pigs. The country’s swineherd continues to recover across the country but has not reached to the level prior to African swine fever outbreak.⁵

Vietnam Suspended NAVET-ASFVAC Vaccine After Dozens of Pigs Died Following Vaccination

In 2022, Vietnamese officials suspended the off-label use of the NAVET-ASFVAC live virus vaccine after it was reported that dozens of the 600 pigs who were given the vaccine in Binh Dinh, Phu Yen and Quang Ngai provinces died after vaccination.⁶

The ARS was notified of the deaths of the pigs. An ARS spokesperson stated:

According to information received from Vietnamese Ministry of Agriculture and Rural Development, it was determined that the deaths were caused by vaccination processes that were out of compliance with ministry guidelines. … The information that USDA-ARS received also reflected that the deaths of post-vaccination pigs could be attributed to the vaccine being administered to pigs at incorrect ages and incorrect dosages, not following the supplier directions, the directions of MARD, nor the guidance of Vietnam’s Department of Animal Health.”⁷

The ARS also confirmed that test results from samples collected from pigs that were vaccinated without supervision by veterinary agencies showed that some of the pigs also tested positive for a field strain of the African swine virus, porcine reproductive and respiratory syndrome virus, porcine circovirus type 2, and other pathogens, including Streptococcuss spp, Staphylococcus and E. coli.⁸
After an investigation, Vietnamese officials said that incorrect vaccination processes that were not in compliance with Ministry guidelines and at incorrect ages and dosages caused the deaths of the pigs and noted that there needs to be stricter supervision during the vaccination process.⁹

U.S. May Purchase African Swine Fever Vaccines

Although there have been no cases of African swine fever in the United States, U.S. Secretary of Agriculture Tom Vilsack said that the U.S is interested in purchasing the vaccines for precautionary purposes.¹⁰

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