Congenital rubella syndrome
If a pregnant woman who does not have immunity to rubella (either due to previous infection or vaccination) catches the rubella virus, it can be passed on to her unborn baby. The virus can disrupt the baby’s development, causing a series of birth impairments that are known as congenital rubella syndrome (CRS).
If a woman catches rubella during the first 10 weeks of pregnancy the chance of her baby being affected by congenital rubella syndrome is as high as 90 per cent and the baby is likely to experience multiple impairments at birth.
If rubella is caught between the 11th and 16th week of pregnancy the risk of CRS occurring falls to around 10 to 20 per cent and it is likely that congenital rubella syndrome will only result in a single sensory impairment at birth.
Birth impairments are rare if an infection occurs after the 16th week. In the past, the most commonly reported birth impairment caused by infection in the later stages of pregnancy was deafness.
Many organs that develop in the early stages of pregnancy can be affected by rubella infection:
- Sensorineural hearing loss in one or both ears
- Cataracts in one or both eyes
- Rarer visual conditions or sight deterioration on ageing
- Heart problems that require significant hospital treatment and affect the child throughout their life
- The brain and nervous system
No two individuals will experience the effects of CRS in the same way.
Before vaccination was introduced in the early 1970s, it is estimated that 200 - 300 infants were born with congenital rubella syndrome in each non-epidemic year in the UK; many more were born in epidemic years. Rubella in pregnancy was responsible for 15 – 20 per cent of significant congenital hearing loss and two per cent of congenital heart disease.
Rubella immunisation was introduced in the UK in 1970 for women of childbearing age and school girls. Since then there have been than 800 babies born disabled as a result of their mothers catching rubella in the early stages of pregnancy. In the same period there have been over 6,500 rubella related terminations.
Since the triple MMR vaccine was introduced in 1988 in the UK there have been just 74 congenital rubella births and only 16 this century; the cases that are reported tend to be to women born abroad who were not immunised as children, and the women themselves have often acquired infection abroad.
Cases of CRS are monitored through the National Congenital Rubella Surveillance Programme.
The World Health Organisation, in 2000, estimated that there were more than 100,000 cases of CRS every year in developing countries.
Long-term health concerns
Scientific research into the effects of congenital rubella syndrome on adults is still limited, but we do know that people with CRS are more likely to suffer from thyroid conditions and diabetes than other people, and at an earlier age. From reports by individuals, families and professionals we also suspect that CRS may cause more frequent or earlier development of other conditions.
As a result it is important that people with congenital rubella syndrome have regular medical check-ups throughout their life and that attention is paid to symptoms of:
- Diabetes mellitus
- An underactive or over-active thyroid
- Glaucoma, retinal detachment and cataracts
- Disturbances in behaviour (it is not certain what may be causing this, and it does not necessarily mean that there is a medical problem)
This list is not exhaustive, and people with CRS report a wide range of health concerns that may or may not be directly linked. However it is important that all symptoms are taken seriously and any treatment recognises the impact of CRS and deafblindness.
First published: Monday 21 May 2012
Updated: Wednesday 3 December 2014