The bigger picture

Chickenpox is a common illness that most people experience during childhood. The main symptom is a rash of red, itchy spots that turn into fluid-filled blisters, which crust over to scabs and eventually fall off. The extent of the rash varies hugely, but pretty much any part of the body can be affected and a fever during the first few days is quite common.

A pregnant woman who is not immune to chickenpox and comes into contact with the condition during pregnancy should seek medical advice promptly from her GP. She can be given an injection of varicella zoster immunoglobulin (VZIG), which strengthens the immune system and can prevent the infection developing, or make it milder and shorter-lived. The injection must be administered within 10 days of contact.

There is a vaccine against chickenpox, which confers around 75 per cent protection when given to adolescents and adults. However, it is not recommended during pregnancy. In fact, women who are given it are advised to avoid conceiving for three months afterwards. Instead it is usually reserved for healthcare workers who have never had the illness and therefore are not immune, because of the risk of them being exposed to it, and individuals living with someone who has lowered immunity, such as the sibling of a child who is receiving cancer treatment, because the risks of complications to the immunocompromised person are considerably higher than usual.