What is Congenital Cytomegalovirus (CMV)?
Congenital
cytomegalovirus (CMV) is a viral infection transmitted from a pregnant individual to their fetus. CMV is a common virus that is part of the herpesvirus family, and it often infects people without causing any symptoms. However, when transmitted
prenatally, it can lead to serious complications in newborns.
How is CMV Transmitted?
CMV can be transmitted from person to person through
bodily fluids such as saliva, urine, blood, and breast milk. In the context of congenital infection, it is primarily transmitted from a mother to her fetus during pregnancy. This can occur if the mother experiences a
primary infection or a reactivation of a prior infection during pregnancy.
Who is at Risk?
Pregnant women who have never been infected with CMV are at higher risk of transmitting the virus to their fetus if they contract it during pregnancy. Additionally, those with weakened immune systems may experience more severe complications.
Healthcare workers and childcare providers are at increased risk due to frequent contact with young children, who are common carriers of CMV.
What are the Symptoms of Congenital CMV?
Most infants with congenital CMV are
asymptomatic at birth. However, about 10% may present with symptoms such as jaundice, petechiae, hepatosplenomegaly, and microcephaly. Long-term complications can include hearing loss, developmental delays, and vision problems. It is important to note that even asymptomatic infants are at risk of developing
sensorineural hearing loss over time.
How is Congenital CMV Diagnosed?
Congenital CMV is diagnosed by detecting the virus in the infant's urine, saliva, or blood within the first three weeks of life. Polymerase chain reaction (
PCR) testing is commonly used to confirm the presence of the virus. Prenatal diagnosis can be performed through amniocentesis to detect CMV DNA in amniotic fluid.
What Treatments are Available?
There is no cure for CMV, but antiviral medications such as
ganciclovir or valganciclovir can be used to treat infants with symptomatic congenital CMV. These medications can help reduce the severity of symptoms and the risk of long-term complications, particularly hearing loss. Treatment is most effective when started early.
How Can CMV be Prevented?
Preventing congenital CMV involves reducing the risk of exposure during pregnancy. Pregnant individuals should practice good hygiene, such as frequent handwashing, especially after contact with young children or their belongings. Avoiding sharing food, utensils, or drinks with young children can also reduce the risk. Research is ongoing for the development of a
CMV vaccine that could provide more comprehensive prevention in the future.
What is the Prognosis for Affected Infants?
The prognosis for infants with congenital CMV varies. Asymptomatic infants generally have a good prognosis, but they require regular monitoring for potential late-onset symptoms. Infants with symptomatic infections may face more significant challenges, including developmental and sensory impairments. Early intervention and treatment can improve outcomes for affected children.
