Intermittently we are asked the question, I have been in close contact (someone who has had face to face contact [e.g. having a conversation] or being in the same room, or within 10 metres for 15 minutes or longer) with a friend or friends children and they have now developed chicken pox and I am pregnant. What do I do?
If you have had chicken pox or shingles in the past you do not need to do anything Most will have had Chickenpox as a child and symptoms are usually mild and once you have had it is is very rare to have it again. Chickenpox infection usually results in lifetime immunity to the virus so re-infection is rare. However, following chickenpox infection the virus remains dormant in spinal and cranial nerve roots and may be reactivated later causing shingles (herpes zoster). So you can develop shingles during pregnancy if if you have had chicken pox in the past. Chickenpox is usually a mild infection but can cause complications in adults and some groups such as pregnant women. Shingles will not affect your baby. Shingles cannot be passed from person to person, however the virus from shingles lesions can cause chickenpox in those who have never had chickenpox before. Approximately 3 in every 1000 pregnant women are affected by chicken pox, and is uncommon in pregnancy due to many already being immune. If you grew up in a tropical or subtropical area, you are less likely to have had chickenpox in childhood and may not be immune.
What is chickenpox?
Varicella zoster virus is a member of the Herpes virus family and causes two common infections, chickenpox and shingles. Chickenpox (varicella zoster) is the primary infection and is highly infectious. It can be transmitted by direct contact with someone who has the blisters (vesicles) from respiratory secretions (airborne) and from contact with contaminated clothing/bedding. It is infectious 2 days prior to the development of the rash and until all the blisters (vesicles) have crusted over.
It can take 10 days to 3 weeks to develop the symptoms of chickenpox from the time you catch it (this is the incubation period). A temperature (fever), feeling unwell and itchy watery blisters mainly over the trunk but extending to the face, scalp and limbs are the symptoms of chickenpox.
What is Shingles?
It begins with increased sensitivity or pain over an area of skin that follows the line of the affected nerve. This is followed by a red itchy vesicular rash over the same area. Transmission of Shingles would be from direct contact with an individual who has the blisters. In can take several weeks for the rash to subside and the area affected can be painful for some time.
I am pregnant and have never had Chickenpox.
If you have never had or been aware that you have had chickenpox and you are exposed to someone with chickenpox or shingles, you should tell your doctor immediately. A blood test can be taken to establish if you are immune looking for the presence of antibodies. Many women are already immune and may have had the chickenpox virus with only mild symptoms that they were unaware of. If you are found to be immune, then you and your baby should not be a risk.
If you are found not to be immune to chickenpox and you come into contact with it during pregnancy, you may be given an injection of varicella zoster immune globulin (VZIG). This is a human blood product that strengthens the immune system for a short time, although it may not prevent chickenpox developing. It is safe to have in pregnancy.
It you catch chickenpox during pregnancy you are at a higher risk of complications to your own health if you are more than 20 weeks pregnant, have lung disease, taken steroids in the last 3 months or a smoker and will need referral to hospital. If you are less than 28 weeks and have chicken pox, you will have an appointment to discuss risks, tests, and specialist scans at a fetal medicine unit
If they don’t find antibodies for the chickenpox virus, you can receive an immunoglobulin injection. This will contain chickenpox antibodies. Getting this injection may mean that you avoid getting chickenpox and possibly shingles in the future, or that you may have a less serious case of chickenpox.
You should tell your doctor that you’re pregnant before receiving an immunoglobulin injection or any other shot. Whether it’s early in your pregnancy or closer to your delivery date, you must be careful with all medicines, supplements, and food that enters your body.
For further information there is detailed advice on the websites below. If you need advice from a healthcare professional if you think you have been in contact with someone with chicken pox/shingles, and are not known to have had chickenpox in the past, please liaise with your GP or Midwife.
Chickenpox and pregnancy patient information leaflet | RCOG
How is chickenpox treated during pregnancy? – NHS (www.nhs.uk)