Cytomegalovirus (CMV) is a member of the herpesvirus family. CMV infects people of all ages and is usually asymptomatic. Some people who acquire CMV infection may experience symptoms similar to those of mononucleosis. After initial infection, the virus establishes lifelong latency and may be intermittently reactivated in those with weakened immune systems. According to the Centers for Disease Control and Prevention (CDC), over half of adults are infected with CMV by age 40.
Pregnant women can pass CMV to fetuses at any time during pregnancy, which can result in congenital CMV infection. This can happen following a primary infection, reinfection with a different CMV strain, or reactivation of a previous infection. Primary infections occur in 1% to 4% of seronegative pregnant women and lead to fetal infection in 40% to 50% of these pregnancies. Maternal CMV reactivation or reinfection with a different CMV strain leads to fetal infection in about 1% of seropositive pregnant women.
CMV is the most common infectious cause of birth defects in the United States. According to the CDC, about 1 in 200 infants are born in the United States with congenital CMV infection each year. This rate equates to about 115 babies born in Idaho with congenital CMV each year. Most infants with congenital CMV are asymptomatic and will not have long-term health problems. However, about 20% of infected infants will experience long-term health problems.
Resources for Pregnancy Care Providers
CMV Fact Sheet- Pregnancy Care Providers
Resources for Pediatric Providers
CMV Fact Sheet- Pediatric Providers