LOS ANGELES, Jan. 11 (Xinhua) -- The National Academy of Sciences (NAS) stressed the urgent need on Monday to raise the awareness of hepatitis threat.

    A campaign should be launched to educate the public, doctors and lawmakers about the diseases, an approach similar to HIV/AIDS outreach that has made that issue prominent in people's minds, the NAS said in a report.

    Hepatitis B and C remain serious threats to public health, but many healthcare providers fail to screen at-risk patients and don't know how to treat those infected with the viral diseases that can cause liver failure and cancer, the NAS said.

    Even though chronic viral hepatitis infections are three to five times more frequent than HIV in the United States, many doctors and nurses do not understand the extent and seriousness of the problem, said the NAS.

    Most of the estimated 3 million to 5 million people with chronic hepatitis B and C don't know they have the diseases, according to the NAS.

    Infected people can show no signs of illness for years, and by the time they start to show symptoms, they may have already developed scarring of the liver or liver cancer and can be close to death, researchers said.

    Although an estimated one percent to two percent of the U.S. population has chronic hepatitis B and C, researchers found that awareness of the diseases remains low.

    Each year lack of awareness contributes to about 1,000 infants contracting Hepatitis B from their mothers during childbirth. Although preventative steps can significantly reduce the likelihood of chronic infection in babies, the number of new infections has not declined in a decade, according to the report.

    Black adults have the highest rate of acute hepatitis B infection in the United States. And although Asian Americans make up less than five percent of the U.S. population, they account for more than half of chronic hepatitis B cases nationwide, according to the report.