SEOUL (REUTERS) - South Korea is intensifying efforts to contain an outbreak of foot-and-mouth disease by inoculating all hogs in affected areas, the agriculture ministry said in a statement on Thursday.

South Korea earlier this month confirmed a fresh case of foot-and-mouth disease at a hog farm, five months after an outbreak elsewhere added to fears about food safety.

So far nine cases have been confirmed at Chungcheong province, about 100 km southeast of the capital Seoul, the ministry statement said.

All outbreaks were the type that animals are inoculated against in South Korea, said the ministry.

Over 13,600 hogs have been slaughtered at the affected farms and Seoul has heightened its foot-and-mouth watch level to alert from caution, it added.

The late July outbreak was the first in more than three years but it came as authorities struggled to contain a continuing problem with bird flu, which has pushed up the price of pork as consumers bought alternative meat.

Livestock disease problems are a big factor behind a jump in pork imports, mainly from the United States and Germany. These rose 21 per cent to 328,241 tonnes in the first 11 months of this year from the same period last year, South Korean customs data showed.