A new test offers a rapid, inexpensive and highly accurate method for screening newborns for cytomegalovirus, which can cause permanent hearing loss, researchers said on Wednesday.

Though one in 150 babies are born infected with cytomegalovirus - known as CMV and part of the herpes virus family - current tests are not effective for widespread screening, the scientists said.

The new test does not require the culturing of blood samples, it employs saliva, easily obtained by swabbing the inside of a baby's mouth.

Of 17,662 newborns screened, all 85 infants identified as infected with CMV by a blood culture test also were identified by the new test, researchers reported in a paper published in The New England Journal of Medicine. Another 17,327 newborns were screened with a different saliva test. It was slightly less accurate, detecting CMV in 74 of 76 infants identified by culturing.

Infected babies must be monitored and tested frequently for hearing loss so that support services can be provided if necessary, said Dr. Suresh B. Boppana, a professor of pediatrics at University of Alabama at Birmingham and one of the paper's authors.