The government will strengthen nationwide monitoring of hepatitis C as part of efforts to prevent a mass outbreak from recurring, officials said Monday.

Hundreds of South Koreans were infected with the virus between 2015 and last year, which causes both acute and chronic infection.

There is currently no vaccine, though about 15 to 45 percent of infected persons are known to spontaneously recover and clear out the virus within six months of infection without treatment.

The Ministry of Welfare and Health said it will examine all hepatitis C cases instead of selected samples starting in early June, as an early diagnosis is crucial to fending off a mass infection.

All hospitals will be required to report cases of hepatitis C and an inspection will be conducted for every case, it said.

Currently, an epidemiological inspection is carried out only in cases voluntarily reported by hospitals or medical facilities.

In South Korea, hepatitis C is classified as a third-level infectious disease, which only 186 medical institutions subject to the government's selected monitoring are obliged to report cases to health authorities.

The rule has made most other hospitals unwilling to report hepatitis C cases to health authorities for fear of government sanctions and negative public sentiment.

Between late 2015 and last year, mass infections of hepatitis C occurred at several hospitals in Seoul and other provincial clinics due to the reuse of disposable syringes.

The mass outbreak sparked calls for the government to unveil a package of measures to prevent the spread of hepatitis C. In September last year, the ministry announced a shift to the examination of all cases.

Hepatitis C is often called the "silent killer" as it is difficult to detect at an early stage. In South Korea, its prevalence rate stands at less than 1 percent, but patients tend to become chronic once infected, according to experts. (Yonhap)