JAKARTA (Reuters) - Nearly 30,000 pigs have died from African swine fever (ASF) in Indonesia’s North Sumatra province as of Dec. 15, causing millions of dollars of economic losses as authorities try to quarantine the areas affected, officials said on Wednesday.

The Agriculture Ministry has declared an outbreak of the highly contagious virus in the country and said it is contained only in some parts of North Sumatra, minister Syahrul Yasin Limpo told reporters.

“Very serious handling is being carried out, including isolating those areas,” Limpo said.

Fadjar Sumping Tjatur Rassa, director of animal health at the Agriculture Ministry, said that ASF has been found in 16 areas in North Sumatra, including the provincial capital Medan, and that authorities were trying to make sure the virus was not being transported out.

Meat and meat products are not allowed to leave the 16 areas affected, and people who have been in contact with infected animals must go through bio-security screening, he said.

“Trade traffic (for pork and its products) are temporarily closed for the infected areas,” Rassa said, adding that North Sumatra has a pig population of 1.2 million.

East Timor, which shares an island with Indonesia’s East Nusa Tenggara province at the far eastern end of the country, reported numerous outbreaks of ASF in September that killed 405 backyard pigs.

ASF has also decimated China’s pig herd since the first outbreaks were discovered last year, triggering a surge in Chinese pork imports and a rise in prices there.