Drug injection, tattooing, body piercing and sexual promiscuity are rising causes of hepatitis C infection in Korea, a study showed Monday.

According to a research team at Seoul National University Hospital in Bundang, Gyeonggi Province, 28 percent of 1,173 respondents who are currently undergoing hepatitis C treatment at five teaching hospitals in Seoul and Busan said they had more than four sexual partners while in a comparison group only 10 percent had as many partners.

Drug injection has also contributed to the hepatitis C increase with 5 percent of respondents saying they had tried it.

The rate of hepatitis C patients who had injected drugs was particularly high in Busan, with 10.3 percent. Eighty percent of the respondents were men, the report said.

“Previous reports so far have shown that the link between injection-drug use and hepatitis C infections was not significant. But the result came out differently when we included patients in Busan,” said professor Chung Sook-hyang who led the team.

“The study is somewhat limited because we included only those in Busan, but we are concerned that the recent cases of hepatitis C in Korea are following footsteps of those advanced countries in North America and Europe,” Chung told Yonhap News Agency.

Hepatitis C is transmitted through body fluids. Blood transfusion was the most frequent cause of the disease but the number of cases fell due to improved hygiene management. Despite these efforts, the number of hepatitis C infection is rising because of diversified infection routes, experts said.

Some reports say about 40 percent of hepatitis C patients in the United States and Italy couldn’t find the causes of the disease. Most people who are infected with hepatitis C don’t have any symptoms for years. Over 75 percent of the people infected with the virus develop a chronic infection.

By Cho Chung-un (christory@heraldcorp.com)