Cytomegalovirus (CMV) infection
What is CMV?
CMV stands for cytomegalovirus. It it a type of virus from the herpes group. Approximately, 50 – 85% of adults in the US have been infected by CMV by the age of 40 years old. Once a person becomes infected the virus remains alive but dormant in the body for life. It usually is harmless and rarely causes any illness. However, in those immunocompromised people it will cause CMV disease.
What are the symptoms of CMV?
Most children and adults remain asymptomatic. However, others may develop the symptoms below up to 2 -3 weeks after exposure:
- Fever
- Swollen glands
- Feeling tired
How does CMV spread?
CMV spreads from person to person. It spread through close intimate contact with infected person whom excrete the virus through their saliva, urine, breast milk or other bodily fluid. It is not highly contagious.
How is it diagnosed?
As majority people remain asymptomatic, CMV infection is rarely diagnosed. However, you could know whether you have been infected previously as the antibody towards the virus remains in your body for life. CMV could be cultured from specimens taken from the urine, throat swabs and blood.
What if I am confirmed having CMV infection. How do I know my baby’s status?
- By doing an amniocentesis test to check the amniotic fluid for the CMV.
- Post delivery by testing the baby’s saliva, urine and blood for the virus.
What is the risk of CMV to a pregnant woman?
Healthy pregnant women are not at higher risk for CMV infection. Approximately, 0.7 – 4% of pregnant women in the US develops primary infection of CMV. Unfortunately, majority of pregnant women infected with CMV are asymptomatic but their developing baby may show signs suspicious of CMV infection in the womb such as enlargement of the brain tissue, enlarged liver and spleen, growth restriction or reduced amniotic fluid (oligohydramnios) which could be detected from ultrasound scan.
What does it mean for my growing baby if I contracted CMV infection?
CMV is one of the common causes of congenital viral infection. Transmission rate to the baby is between 24 – 75%, with an average transmission rate of 40%. Of the 40% of infected baby, only 10% shows signs of CMV infection after a primary infection of the mother. Possible complication to the baby include:
- Enlargement of the liver and spleen
- 80 – 90% develops hearing loss, visual impairment and varying severity of mental retardation in their first few years of their life.
- 5-10% has no symptoms at birth but develop varying degrees of hearing, mental or problems with their movement and balance.
If the mother has been infected with CMV about 6 months before pregnancy, the rate of newborn CMV infection is only 1% and their babies do not have any significant abnormalities or illness. However, infected pregnant women are encourage to breast feed their baby as the benefits of breast feeding outweighs the minimal risk of transmitting the CMV.
What is the treatment of CMV?
During pregnancy, if there is severe CMV infection, the pregnant women could be treated with several medications. However, there are no vaccines for CMV currently.
Which group is at higher risk of getting CMV infection?
- Lower socioeconomic group
- People who work with children as CMV is commonly transmitted among children.
- Immuno-compromised people e.g HIV patients or organ transplant recipient
Could CMV be prevented?
Yes, CMV infection could be prevented by the following steps:
- Practice good hygienes including frequent hand washing with soap and water.
- If you develop flu like illness you may want to ask your doctor to check for CMV infection
- Avoid sharing food, eating or drinking utensils
I work with children, what should I do?
- Child care worker should practice good hygiene as CMV is transmitted through contact with infected bodily fluid such as urine and saliva.
- There is no recommendation to routinely transfer susceptible non pregnant women working with children to other working environment
