While you might know all about other risks in pregnancy and for babies, CMV is one that is far less well known. Here’s why you should be aware of it…
CMV, or cytomegalovirus, is a common virus that can affect you whatever age you are.
If you have CMV, it’s likely you won’t have any signs or symptoms or any long-term effects. Yet the reason it’s something to be aware of in pregnancy is that it can be very dangerous to unborn babies. In fact, passing CMV to your baby when you’re pregnant (congenital CMV) is one of the most common causes of birth defects in the UK (NHS, 2017).
"About one third of women who get CMV for the first time while they’re pregnant will pass the virus to their unborn babies (Kenneson et al, 2007)."
CMV: how common is it?
Lots of people think it’s rare because CMV is a relatively unknown condition. Actually though, it’s more common than Down’s syndrome, Toxoplasmosis, spina bifida or cystic fibrosis.
As many as one in 150 newborn babies are born with congenital CMV each year (Dollard et al, 2007; Kenneson, 2007; Townsend et al, 2011). Congenital CMV is responsible for around 25% of childhood hearing loss (Manicklal et al, 2013).
CMV is found in bodily fluids, including urine, saliva, blood, mucus and tears (NHS, 2017).
It’s really common for small kids – especially those who go to nursery or playschool – to catch CMV (Cannon et al, 2014).
The main way a pregnant woman catches CMV is from the saliva and urine of young children (Cannon and Davis, 2005). This means pregnant women who have young children or work with young children should be especially careful (Cannon and Davis, 2005; Joseph et al, 2006).
At the moment, there’s no vaccine against CMV so ways to protect yourself include:
- Washing hands after changing nappies, wiping noses, feeding etc.
- Washing toys or other things that get children’s saliva on them.
- Not sharing cups etc. with your young children.
- Avoiding kissing babies, toddlers and small children directly on the mouth. Kiss them on the forehead or cheek instead.
(Stowell et al, 2013)
CMV: what are the symptoms in adults?
If you have CMV, it’s likely you won’t know you have it but you might get symptoms in the form of:
- a fever
- a sore throat
- swollen glands.
It’s not easy to diagnose but if you do develop the above flu-type symptoms when you’re pregnant, speak to your GP.
CMV: what are the symptoms in children?
Most babies born with CMV won’t have any symptoms. Yet around two or three babies every day – one in 1,000 – born in the UK every year will have a permanent disabilities as a result of CMV (Dollard et al, 2007; Kenneson, 2007; Townsend, 2011).
In an unborn baby, the signs of congenital CMV infection are:
- small growth rates
- small head size (microcephaly).
(Goderis et al, 2013)
When the baby is born, if they show symptoms, they might include:
- little red spots (petechiae)
- enlarged liver and spleen
- calcium deposits in the brain
- developmental or learning difficulties
- hearing loss.
(Goderis et al, 2013)
Some children with congenital CMV go on to develop:
- autism visual impairment
- cerebral palsy
(GOSH NHS Trust, 2012; CMV Action, 2018)
Unfortunately, there’s no treatment for CMV when you’re pregnant (NHS, 2017). Newborns with symptoms can be treated with antiviral treatments (NHS, 2017).
You can also manage hearing loss from CMV with hearing aids and cochlear implants.
After that, all babies born with congenital CMV will be monitored regularly. They’ll have a full range of tests after CMV has been diagnosed, which will include:
- blood count, platelet count and liver function tests
- brain scan
- hearing test
- eye test.
Their growth and development should be regularly monitored too.
CMV diagnosis in adults
Most CMV infections aren’t diagnosed because you’ll have few or no symptoms. A blood test can show if you have it or have had it previously though.
If you have had it, bear in mind that it is possible to get it again (NHS, 2017).
CMV diagnosis in children
You can confirm whether a newborn has the CMV virus with a saliva, urine or blood test (CMV Action, 2018).
Just make sure the test is done in the first three weeks of a baby’s life to make sure that it is a congenital CMV infection (CMV Action, 2018). If they caught CMV during or after birth, it won’t cause any long-term problems (CMV Action, 2018).
This page was last reviewed in July 2018.
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Cannon M, Stowell J , Clark R , Dollard P , Johnson D , Mask K , Stover C , Wu K, Amin M, Hendley W , Guo J , Schmid S, Dollard S. (2014) Repeated measures study of weekly and daily cytomegalovirus shedding patterns in saliva and urine of healthy cytomegalovirus seropositive children. BMC Infectious Diseases (14):569 Available from: https://www.ncbi.nlm.nih.gov/pubmed/25391640 [Accessed 1st July 2018]
Cannon MJ, Davis KF. (2005) Washing our hands of the congenital cytomegalovirus disease epidemic. BMC Public Health (5):70. Available from: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC1182379/ [Accessed 1st July 2018]
CMV Action. (2018) Diagnosis and symptoms in babies. Available from: https://cmvaction.org.uk/what-cmv/diagnosis-symptoms [Accessed 1st July 2018]
Dollard SC, Grosse SD, Ross DS. (2007) New estimates of the prevalence of neurological and sensory sequelae and mortality associated with congenital cytomegalovirus infection. Rev Med Virol 17(5):355-363. Available from: https://www.ncbi.nlm.nih.gov/pubmed/17542052 [Accessed 1st July 2018]
Goderis J, De Leenheer E, Smets K, Van Hoecke H, Keymeulen A, Dhooge I.
(2013) Hearing loss and congenital CMV infection: a systematic review. Pediatrics. (5):972-982. Available from: https://www.ncbi.nlm.nih.gov/pubmed/25349318 [Accessed 1st July 2018]
GOSH NHS Trust (Great Ormond Street Hospital for Children). (2012) Congenital cytomegalovirus (CMV) infection. Available from: https://www.gosh.nhs.uk/file/983/download [Accessed 1st July 2018]
Iwasenko JM, Howard J, Arbuckle S, Graf N, Hall B, Craig ME, Rawlinson WD. (2011) Human cytomegalovirus infection is detected frequently in stillbirths and is associated with fetal thrombotic vasculopathy. J Infect Dis. 203(11):1526-1533. Available from: https://academic.oup.com/jid/article/203/11/1526/862620 [Accessed 1st July 2018]
Joseph SA, Béliveau C, Muecke CJ, Rahme E, Soto JC, Flowerdew G, Johnston L, Langille D, Gyorkos, TW. (2006) Cytomegalovirus as an occupational risk in daycare educators, Paediatr Child Health. 11(7): 401–407. Available from: https://www.ncbi.nlm.nih.gov/pubmed/19030309 [Accessed 1st July 2018]
Kenneson A, Cannon MJ.(2007) Review and meta-analysis of the epidemiology of congenital cytomegalovirus (CMV) infection. Rev. Med. Virol. (17):253-276 Available from: https://www.ncbi.nlm.nih.gov/pubmed/17579921 [Accessed 1st July 2018]
Manicklal S, Emery VC, Lazzarotto T, Boppana SB, Gupta RK.(2013) The ‘silent’ global burden of congenital cytomegalovirus. Clinical Microbial Rev. 26(1):86-102 Available from: https://www.ncbi.nlm.nih.gov/pubmed/23297260 [Accessed 1st July 2018]
NHS. (2017) Cytomegalovirus (CMV). Available from: http://www.nhs.uk/Conditions/Cytomegalovirus/Pages/Introduction.aspx [Accessed 1st July 2018]
Stowell JD, Forlin-Passoni D, Radford K, Bate SL, Dollard SC, Bialek SR,
Cannon MJ, Schmid DS.(2013) Cytomegalovirus Survival, Transferability, and the Effectiveness of Common Handwashing Agents against Cytomegalovirus on Live Human Hands. Appl. Environ. Available from: https://www.ncbi.nlm.nih.gov/pubmed/24185855 [Accessed 1st July 2018]
Townsend CL, Peckham CS, Tookey PA. (2011) Surveillance of congenital cytomegalovirus in the UK and Ireland. Arch Dis Child Fetal Neonatal Ed. 96(6):F398-403. Available from: https://www.ncbi.nlm.nih.gov/pubmed/21289013 [Accessed 1st July 2018]