Viral infections linked to cerebral palsy

Exposure to certain viral infections around the time of birth is linked to cerebral palsy. Neurotropic infections - viral infections that target nerves, which include the herpes viruses, mumps and measles – can trigger brain damage leading to cerebral palsy, a group of disorders that impairs the control of movement. Cerebral palsy is caused by poor development or damage to the motor areas of the brain. Signs of the disorder usually appear before the age of three. The severity of symptoms varies. There is no cure but drugs can help to control seizures and spasms along with physical, occupational and behavioural therapy. The risk of cerebral palsy is nearly doubled with exposure to the group B herpes viruses (Varicella zoster and human herpes viruses 6 & 7). But other factors such as a susceptibility to infection or prematurity may be needed for the disorder to develop. Researchers from the University of Adelaide Gibson, Australia, analysed blood samples taken within a few days of birth from 443 children with cerebral palsy and 883 other babies. It was found that group B herpes viruses were found more frequently in children later diagnosed with cerebral palsy. Neurotropic viruses can cross the placenta and infect the baby shortly before or after birth. The researchers said the likelihood of the mother's infection crossing into the fetus depended on the virus, whether the infection was recurrent and the age of the fetus at the time of the infection. Perinatal exposure to neurotropic viruses is associated with preterm delivery and cerebral palsy. However, it is unclear how perinatal (around the time of birth) exposure to viral infection causes subsequent brain damage and cerebral palsy.