One of the European Union's poorest states, Bulgaria has so far detected more than 30 outbreaks of the disease at industrial or backyard farms and around 130,000 pigs have already been culled, reports Reuters.
Experts say the Balkan country could lose its entire pig breeding industry and have its 600,000 pigs culled, while industry officials fear it could cause damages of up to 2 billion levs ($1.15 billion).
An outbreak of African swine fever in China is forecast by experts to wipe out about a third of Chinese pork production this year, or 18 million tonnes, twice the amount of pork exported worldwide every year.
China is not the only country hit. There have been outbreaks in Vietnam, Cambodia, Mongolia, North Korea and Laos. It has also already spread across parts of central and eastern Europe and even been found in wild boars in Belgium.
Last month Sofia announced measures to prevent the spread of the highly contagious disease, and protect the pig-breeding industry in Bulgaria, where almost every household in rural areas keeps home-raised pigs and has so far detected.
But Deputy Agriculture Minister Yanko Ivanov admitted that the government had failed to prevent the spread of the virus, which has already hit more than a dozen districts.
"What we failed to do was reduce the population of wild boar, which, unfortunately, has a fairly dense concentration in the areas with industrial farms," Ivanov said.
The agriculture ministry said last month that forestry enterprises would pay 150 levs ($85.91) for each wild boar killed as the authorities were aiming to reduce significantly the population density in 20km zones around the outbreaks.
"We have also failed with the private backyard farms, which also, in many places, are without any security measures," Ivanov added.
Last week, 20km (12.4 miles) sanitary zones around all registered industrial pig farms were set up, with authorities ordering the culling of home-raised pigs in these zones.
Protest rallies, however, were held in several parts of southern Bulgaria with hundreds resisting government orders, saying there had been no swine fever outbreaks in their regions.
Analysts say the price of pork in Bulgaria has increased by up to 30 percent in less than a month because of the outbreaks and could rise by a further 15 percent in the autumn.
Bulgaria will receive 2.9 million euros ($3.25 million) in EU financial aid to combat the disease, Agriculture Minister Desislava Taneva said after meeting European Commissioner for Health and Food Safety Vytenis Andriukaitis on Tuesday.
Last month Andriukaitis said he was "deeply disappointed" by the efforts by Bulgarian authorities to tackle the outbreak.
Bulgaria has also requested emergency aid of 11 million euros for actions already carried out at industrial pig farms.