Cytomegalovirus (si-to-MEG-a-lo-vi-rus) (CMV) is a common virus found throughout the world and affects people of all ages.  A CMV infection is often "silent," meaning there are no signs or symptoms, and leads to no long-term consequences for the majority of those infected.  However, when an infant is born with a CMV infection (this is called congenital CMV infection) there is a different story.

An estimated 30,000 to 50,000 infants are born each year in the United States with a congenital CMV infection.   The majority will have no symptoms; however, 10 -15 out of every 100 will develop significant problems as a result of their infection.  Development of hearing loss is the most common concern.  Even though hearing may be normal at birth, hearing loss due to congenital CMV infection can develop later in childhood.  Infected children may also develop neuromuscular disorders, developmental disabilities, and visual impairment as a result of their infection.

CMV infection may also be a particular concern for people with a suppressed immune system, such as transplant patients or people infected with HIV.

Currently most infants born in the United States undergo hearing screening before leaving the hospital.  However, since CMV-related hearing loss is often not present at birth, a significant proportion of children with CMV-related hearing loss are not identified by a newborn hearing screen.  The CMV & Hearing Multicenter Screening (CHIMES) Study is expected to provide answers to important questions regarding the role played by congenital CMV infection in childhood hearing loss and whether or not it would be advantageous to screen all newborns for CMV infection at birth in addition to current newborn hearing screening programs.

For more information for parents, please download the following documents:
(In Adobe Acrobat)

The CHIMES Study "Hearing & Speech Milestones" Handout (English)
The CHIMES Study "Hearing & Speech Milestones" Handout (Spanish)
The CHIMES Study "CMV Information for Parents" Brochure (English)
The CHIMES Study "CMV Information for Parents" Brochure (Spanish)