Philippines unveils new technologies to detect and manage African Swine Fever

Three new technologies to detect and manage African Swine Fever have been unveiled in the Philippines amid ongoing concerns about a vaccine imported from Vietnam.

African Swine Fever, which causes haemorrhagic fever in pigs, has had a devastating effect on the country’s swine industry, with outbreaks occurring in 76 out of 82 provinces since 2019 and six provinces recording active cases last month.

Vietnam is also battling a serious outbreak, with thousands of pigs infected.

The Philippines’ Department of Science and Technology (DOST) and Filipino-owned life science company BioAssets Corporation have developed a rapid DNA extraction kit and real-time detection kit for farmers.

A mobile biocontainment laboratory, developed by BioAssets Corporation, is designed to support rapid response to potential outbreaks and improve disease surveillance, enabling farmers to diagnose the disease on-site.

DOST Secretary Renato U. Solidum, Jr. said the interventions demonstrated how science, technology and innovation can offer “holistic solutions to pressing animal health challenges” impacting food security.

However, Fermin Diaz, editor of the online magazine Livestock and Meat Business, told SciDev.Net: “The way I look at it, it seems that these new tools are just palliatives … so that the DOST can say that they are addressing the matter.

“Those kits have very minimal contribution to the overall diagnostic aspect of disease management.”

African Swine Fever is a highly contagious viral disease affecting domestic and wild pigs, with mortality rates as high as 100 per cent. It has caused huge economic losses and disruption to the pork supply chain, threatening food security across the region.

If left unchecked, there is a risk that the virus could mutate, potentially making it more transmissible or virulent.

The Philippine government, with the assistance of the UN Food and Agriculture Organization (FAO), has adopted a three-pronged strategy to combat the virus in the last year, focused on prevention, control and vaccination.

Constante Palabrica, the Philippines’ agriculture undersecretary for livestock, said cases were going down thanks to “zoning and checkpoints” as part of the new programme. He noted that no microbial mutations have been identified.

According to official figures, more than 495 cities and municipalities have been upgraded from “red” infected zones to “pink”, meaning they are no longer under quarantine.

Vaccine controversy

The Philippine government has imported large quantities of the Vietnam-made AVAC vaccine, despite concerns over trial data, it emerged at a House of Representatives committee meeting on trade, industry and agriculture in June.

The vaccine was distributed to local livestock raisers in a bid to prevent mass deaths of farmed pigs, a source of livelihood for thousands of people.

But the move alarmed some who fear a repeat of the experience in Vietnam with live attenuated vaccines — a live vaccine which has been weakened — where it affected the health of pigs.

“The nationwide implementation of Live Attenuated Vaccines in Vietnam for prophylaxis has likely influenced the viral genetic pool among the swine population,” said an article published in the journal Scientific Reports.

The Philippines’ Food and Drug Administration said in 2024 that field trials had been ongoing in the country for almost two years and claimed that the vaccine had a 100 per cent efficacy with no side effects. However, no trial data has been made public.

“I would like to express grave concern over the vaccine trials,” said representative Ferjenel Biron, a doctor of medicine, during the 11 June Congressional hearing.

He questioned why a Certificate of Public Registration was issued despite two veterinarians who evaluated the AVAC vaccine deeming it to be unsafe.

According to Diaz, the vaccine has a low acceptance rate among farmers in the Philippines, with only about “five to ten per cent” using it.

“The product is being heavily and indiscriminately endorsed by the Department of Agriculture … with very inadequate orientation taken about the product’s risks and downside effects,” he added.

An association of swine raisers in Batangas province told SciDev.Net it was concerned about using the vaccine on swine herds.

“We won’t take the risk,” the group representative said on condition of anonymity. “It’s still experimental.”

The AVAC ASF LIVE vaccine, was created by AVAC Vietnam JSC and imported into the Philippines by KPP Powers Commodities Inc. It is derived from a virus strain called ASFV-G-MGF, or MGF.

In 2022, the US Department of Agriculture issued a public notice warning that MGF had “the potential to pose a severe threat to animal health or animal products”.

“It has also been determined that the virus strain is not safe for use in pigs because its genome is unstable, potentially leading to reversion of virulence,” the notice warned.

Low vaccination rate

Nguyen Van Diep, general director of AVAC Vietnam Joint Stock Company and project leader for the ASF vaccine, said the vaccine been in use since July 2022.

“The reason that outbreaks still occur is because of the low vaccination rate,” he told SciDev.Net. “According to our estimates, at any given time, it is at less than five per cent.’’

Disputing that the vaccines from AVAC sent to the Philippines were substandard, Diep said vaccine-makers adhered to strict standards on quality and highlighted the perishable nature of vaccines.

“Preserving a live-attenuated vaccine is also important. It should be kept at 2 to 8C. It has a shelf life of 24 months from the date of manufacture,” he said.

Since the first outbreak in China in 2018, 20 countries have reported African Swine Fever, according to the World Organisation for Animal Health.

Lionel Dabbadie, FAO representative in the Philippines, told SciDev.Net: “There is no cure as of today, so traditional control measures, such as culling infected and susceptible animals, enforcing stringent biosecurity protocols, and restricting the movement of pigs and pork products have been the main control method used so far,” Dabbadie told SciDev.Net.

He stressed that a multi-faceted approach was crucial to stem the disease. “Vaccines are promising, but they are not a panacea,” he said.