Concerns over foot-and-mouth disease spreading have escalated across the nation as another suspected case was found in the area surrounding Seoul on Monday, with dozens of cases detected in other regions since last month.

Three pigs at a farm in Yongin, Gyeonggi Province, were reported to have shown common symptoms of foot-and-mouth disease, with bleeding and blisters formed on their bodies, the city government said.

This is a second case found in the region following one confirmed in Icheon, Gyeonggi Province, late last month.

The pigs tested positive in a preliminary test, quarantine officials said. The final test results will be available Tuesday.

Since the first case broke out in Jincheon, North Chungcheong Province, on Dec. 3, foot-and-mouth disease has spread across the country. As of Monday, more than 26,000 animals at 32 farms have been culled, with most in North Chungcheong Province.

The source of the disease outbreak is currently under investigation, but it is suspected to be unvaccinated pigs, the Ministry of Agriculture, Food and Rural Affairs said.

The quarantine authorities claim that the spread of the disease will not be as rapid as before, citing vaccination measures.

“Once antibodies are created in vaccinated animals, the viral disease will no longer spread,” Agriculture Minister Lee Dong-phil said. “The occurrence rate of this outbreak accounts only for 4 percent of that in 2010-11.”

More than 800 cases were reported in late 2010.

Concerns remain, however, as the infected pigs in Yongin were found to have only been vaccinated after the disease broke out last month.

As part of the efforts to contain the foot-and-mouth infection, the government vowed to step up the quarantine measures.

All livestock-related trucks will be put under control for disinfection measures on Wednesday, the Agriculture Ministry said. This is the second nationwide sterilization measure following the first one taken last week.

Farm owners skipping vaccination will also face toughened penalties such as a fine of up to 5 million won ($4,500) or cancellation of their livestock permit, the ministry said. The compensation for animal culling will also be reduced for animals that are not vaccinated, it added.

South Korea has been hit five times by foot-and-mouth disease since 2000, with three occurrences in 2010.

More than 3.4 million animals were slaughtered in the largest outbreak in late 2010, resulting in losses of more than 2.7 trillion won.

By Lee Hyun-jeong  (rene@heraldcorp.com)