Link Between Newborn Infection and Childhood Hearing Loss?
NIDCD-funded Researchers to Lead a Multicenter Study
NIDCD-supported researchers are investigating the link between a common infection that is spread from person to person through bodily fluids—saliva, tears, blood, semen, vaginal secretions and breast milk—and childhood hearing loss. In one of the largest studies of its kind, 100,000 babies will be screened for cytomegalovirus infection at birth to determine the role of CMV in childhood hearing loss. Those who test positive for CMV will undergo hearing screening to determine the onset, severity, and progression of hearing loss. The seven-year, $15 million contract, which is currently in protocol development, is being led by scientists at the University of Alabama School of Medicine.
University Hospital at University of Alabama
Although a majority of infants born in the United States are already screened for hearing loss, most infants are not tested for CMV unless they already show signs of the disease. Also, newborn hearing screening cannot detect or predict hearing loss that will occur later in childhood. While the causes of childhood hearing loss remain largely unknown, estimates indicate that as much as 20 to 30 percent of childhood hearing loss is caused by CMV infection.
CMV, a member of the herpes family, is the most common infection passed from a mother to her unborn child. Approximately one percent of newborns, or about 40,000 infants each year, are born infected with CMV. Children born with CMV infection who have symptoms of infection, such as hearing loss, seizures, visual impairment, and cerebral palsy, are usually identified at birth and receive appropriate medical care.
However, the majority of CMV-infected children—roughly 90 percent—have no symptoms at birth. These children have what is called a "silent" infection, which often goes unnoticed. About 10 percent are at risk for eventually developing hearing loss—the most common outcome of CMV infection. Identifying asymptomatic children and following their progress to determine if hearing loss develops is a major focus of this research.
In this study, newborns at seven institutions* around the country will be screened for CMV infection at birth, in addition to receiving newborn hearing screening. Most of the newborns will be enrolled for screening and follow-up evaluation beginning in about a year.
The researchers will analyze the data to better understand the relationship between CMV infection and hearing loss and to determine the extent to which CMV screening together with hearing screening can improve the detection and prediction of permanent hearing loss in children.
*In addition to the University of Alabama, Birmingham, AL, which is coordinating the research for this contract, other participating institutions are: University of Mississippi, Jackson, MS; Carolinas Medical Center, Charlotte, NC; St. Peter's University Medical Center, New Brunswick, NJ; University of Cincinnati, Cincinnati Children's Medical Center; University of Pittsburgh, Children's Hospital of Pittsburgh; and the University of Texas, Southwestern Medical Center, Dallas, TX.