What is chickenpox?

Chickenpox, also known as varicella, is an infectious disease cause by the varicella-zoster virus.

Chickenpox can affect people at any age. The disease is more severe in pregnant women and people with compromised immune systems.

If you've had chickenpox it can come back later in life in the form of shingles (herpes zoster).

What are the symptoms of chickenpox?

Chickenpox symptoms usually start around 2 weeks after infection with the chickenpox virus.

Look out for an itchy red rash that turns into blisters which burst and form a hard crust.

Often, chickenpox will also cause flu-like symptoms such as:

• headache
• fever
• sore throat

You can expect these symptoms to last between 10 and 21 days.

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How is chickenpox spread?

Chickenpox is very contagious. It spreads quickly among people who have been in contact with an infected person and aren't immune — from previous vaccination or previous infection.

A person with the chickenpox virus can spread the disease in 2 ways:

1. Early in the illness, before the rash appears, the virus spreads through cough droplets that travel through the air. This means that an infected person can spread chickenpox before they know that they are sick.
2. Later in the illness, once symptoms have developed, the virus is also spread through contact with the fluid in the blisters.

You are contagious until all the blisters have dried up and formed a crust. This is usually about 5 to 6 days after your symptoms start but can be as long as 3 weeks. You shouldn't meet up with other pregnant women and infants until your blisters have crusted over.

How can chickenpox affect my pregnancy?

Chickenpox can be a serious disease in adults. Infection during pregnancy can also affect the health of your baby.

If you are exposed to chickenpox during pregnancy, contact your doctor or midwife straight away. They may suggest an injection of antibodies. This can't be given after you develop symptoms of chickenpox. Instead, you will be given antiviral medicine.

How can chickenpox affect my unborn baby?

If you get chickenpox while you're pregnant, it may affect your unborn baby. The effect on your baby depends on many factors, including how many weeks pregnant you are.

There's no evidence of an increased chance of miscarriage in your first trimester.

There is a small risk that your unborn baby could develop foetal varicella syndrome (FVS), if you get chickenpox in the first 28 weeks of pregnancy.

Foetal varicella syndrome can cause:

• skin scarring
• eye problems
• small limbs
• brain and neurological problems

Your doctor will suggest that you have a detailed ultrasound scan 5 weeks after infection.

Chickenpox, labour and birth

If you're infected in your last 4 weeks of pregnancy — the virus may be active in your baby at birth. This happens for about 1 in 2 babies.

If you have chickenpox at the time of birth, you can still breastfeed if you're well enough and wish to do so.

Your baby is more likely to get severe chickenpox if you have chickenpox the week before or the week after giving birth. Because of this risk your doctor may treat your baby with antibodies and antiviral medicine once they are born. This helps to stop them getting the disease.

When should I see my doctor?

If you are pregnant and think you may have chickenpox, you should call your doctor immediately.

Do not go to the clinic since you don't want to infect other people in the waiting room. Rather, call your doctor and they will let you know the safest way to see them.

If you're pregnant and have had contact with someone with chickenpox you should also contact your doctor or midwife. They may suggest that you're given antibodies to protect you from infection. Receiving this injection within 10 days of exposure may lower your chance of catching chickenpox. If a rash does develop you should contact your doctor or midwife.

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How can I prevent chickenpox?

The best way to protect yourself against chickenpox is through vaccination. Most vaccinated people will not get chickenpox. Those that do get infected will generally have a milder form of chickenpox with:

• fewer blisters
• a lower fever
• a quicker recovery

The chickenpox vaccine will also protect you against getting shingles later in life.

Vaccination during pregnancy isn't advised.

I'm planning a pregnancy — should I be vaccinated?

If you are planning a pregnancy you should see your doctor for a pre-conception health check.

If you've never had chickenpox and aren't vaccinated, now is a good time to get vaccinated.

Your partner might also want to consider getting vaccinated. The chickenpox vaccine is recommended for all adults who have never had chickenpox or previously been vaccinated.

Timing is important for pre-pregnancy vaccination. It's recommended that 2 doses of chickenpox vaccine are given at least 4 weeks apart. The second dose should be given at least one month before stopping contraception.