Seven youths who were given unheated imported blood products at a hospital in Shizuoka Prefecture in the early 1980s have hepatitis C, hospital officials said Monday.
The hospital recently sent letters to about 40 other youths who were given the blood products as newborns, telling them to be tested for the disease after doctors realized the products may have contained the virus, the officials said.
The hospital requested anonymity to protect the patients' privacy.
According to the hospital, the infections were discovered when a 20-year-old male student, who had an operation at the hospital as a newborn, was found to have a hepatitis C-type virus this spring.
The hospital made a list of patients who had been treated with unheated blood products in the early 1980s for diseases other than hemophilia and found that six others had already been treated for hepatitis, the officials said.
Hepatitis C is usually spread via blood transfusions and needle sharing. It can cause liver cirrhosis, which may lead to liver cancer.
The blood products were generally used to treat hemophiliacs, but they were also used as coagulating agents for treating newborns and traffic-accident victims, the officials said.
According to a Health and Welfare Ministry survey, unheated blood products were administered to at least 2,600 patients, apart from hemophiliacs, throughout Japan.
HIV infections through transfusions to nonhemophiliac patients came to the public's attention in Japan as a "fourth route of HIV infection."
The seven patients had undergone HIV tests, which were negative, but had not been checked for hepatitis.