Congenital cytomegalovirus

Evidence 

https://pubmed.ncbi.nlm.nih.gov/26410438/ 

Mitchell M Pitlick, Kristin Orr, Allison M Momany, Erin L McDonald, Jeffrey C Murray, Kelli K Ryckman  

Preterm birth is a global public health problem that is a significant cause of infant morbidity and mortality. Congenital cytomegalovirus (CMV) infection has been proposed as a risk factor for preterm birth, but the rate of CMV in infants born preterm is unclear. CMV is the leading infectious cause of sensorineural hearing loss, which will affect 15% - 20% of congenitally infected infants later in their childhood. 90% of infected infants are asymptomatic at birth and are not recognized as at risk for CMV-associated deficits.  

Education 

What is cytomegalovirus (CMV)? 

Cytomegalovirus is a common virus that circulates widely in the community. It is spread from person to person by contact with body fluids e.g. saliva, urine. Healthy people infected with CMV often experience no symptoms or only a mild flu-like illness.  

However, if a pregnant woman is infected with CMV, there is a risk that her unborn baby will also become infected with this virus. This is called congenital CMV.  

What are the risks of congenital CMV?  

Most of the 2000 babies born with congenital CMV infection in Australia each year will remain well. However around 400 will have some level of disability – which can include hearing and vision loss, cerebral palsy, developmental delay or learning problems. In rare cases, CMV can cause stillbirth and neonatal death.  

The highest risk to the unborn baby is when their mother experiences a CMV infection for the first time during the first half of pregnancy. If this happens, there is a 1-in-3 chance of a woman passing CMV to her unborn baby.  

Over half of pregnant women will have had CMV before pregnancy, however it is also possible to be reinfected by a different strain of the CMV virus. Therefore, all pregnant women whether they have had the virus before should take precautions to reduce the risk of infection in pregnancy.  

How can you protect your unborn baby from Congenital CMV? 

People who work with or care for young children are at increased risk of picking up CMV. So women who are pregnant or are planning pregnancy can reduce their risk of CMV by taking the following steps:  

Wash with care 

• Wash hands often with soap and water for at least 15 seconds and dry them thoroughly. This should be done after close contact with young children, changing nappies, blowing noses, feeding a young child, and handling children’s toys, dummies/ soothers.  

Kiss with care 

• Avoid contact with saliva when kissing a child – try a kiss on the cheek or head rather than the lips

Don’t share 

• Don’t share food, drinks, eating utensils or toothbrushes with young children

Who should be tested for CMV?  

CMV testing is not recommended for all pregnant women. Testing for CMV may be recommended for pregnant women who have flu-like symptoms or when an ultrasound reveals a fetal problem.  

Pregnant women and women planning pregnancy may wish to talk about CMV testing with their doctor, if they are at higher risk of CMV e.g. they work with or care for young children.  

All pregnant women should take precautions to reduce their risk of infection in pregnancy.  

Who should be tested for congenital CMV?  

CMV testing is not recommended for all babies. Babies born to mothers diagnosed with CMV infection in pregnancy should be tested for CMV. Hearing loss is the most common sign of congenital CMV. Babies who do not pass the hearing test at birth should also be tested for CMV.  

Can maternal CMV be treated?  

Women diagnosed with CMV infection during pregnancy should see a specialist doctor about treatment options which for some women can include antiviral therapy to help reduce the risk of passing the virus on to her developing baby.    

Can congenital CMV be treated?  

Babies born with problems from congenital CMV should be seen by a specialist paediatrician. Early antiviral treatment can help some babies who are born unwell with CMV, to reduce the risk of hearing loss and other disabilities. Babies infected with CMV should have their hearing and vision assessed regularly. This is because problems may not be seen at birth. 

Empowerment

“While we wouldn’t change our boy for anything, we want people to be aware of CMV. More importantly, reducing the risk to mums-to-be and unborn babies is as easy as communicating a simple message – wash your hands, don’t share utensils, food or drink with toddlers and avoid contact with bodily fluids such as mucus and dribble. If this simple message can prevent future families from having the heartbreaking conversations my husband and I have been forced to endure, then let’s spread the word,” Pam  

“I met a pregnant mum at a kid’s birthday party recently by chance, who was diagnosed with a primary CMV infection. She said she felt so alone, and she experienced all the emotions that I had. There are others in the same situation. If you have CMV and are pregnant, reach out and connect with others.” Miff  

Special thanks to Cerebral Palsy Alliance for content sharing and providing support for families.https://cerebralpalsy.org.au/ 

Useful Links  

Congenital CMV Association of Australia  

Peer to peer support and family advocacy  

www.cmv.org.au 

Cerebral Palsy Alliance  

http://www.cerebralpalsy.org.au/cmv/  

https://cerebralpalsy.org.au/research/research-projects-priorities/cmv/cmv-resource-hub/ 

Raising Children 

https://raisingchildren.net.au/pregnancy/health-wellbeing/pregnancy-health-problems/cytomegalovirus-cmv-infection-pregnancy 

The Sydney Children’s Hospitals Network CMV fact sheet http://www.schn.health.nsw.gov.au/ 

NHMRC Staying Healthy - Preventing infectious diseases in early childhood education and care services (5th Edition) https://www.nhmrc.gov.au/  

Virology Research Laboratories POW Hospital, UNSW www.virologyresearch.unsw.edu.au