Worried about chickenpox? Here's everything you need to know about chickenpox, how to treat and how to prevent it.
Chickenpox is a common childhood illness. More than 95% of un-immunised Australians contract chickenpox as children, when it is a relatively mild infection. But chickenpox in adults, people with suppressed immune systems and pregnant women is much more severe and can be further complicated by pneumonia.
It’s important to know how this virus spreads and how to protect yourself against it.
What is chickenpox and how is it spread?
Chickenpox (varicella) is a viral infection caused by the varicella zoster virus (also known as the herpes zoster virus). Chickenpox is spread from person to person when an infected person breathes, coughs, sneezes or even talks, releasing tiny infected particles into the air. These particles can be transported long distances on air currents and remain in the air for several hours before being inhaled by another person.
Chickenpox can also be spread by coming into contact with or breathing in the blister fluid of a person with the infection.
Once you’ve been infected with chickenpox, the virus remains dormant in nerve cells next to your spinal cord for the rest of your life. If the virus reactivates later in life, rather than getting chickenpox again you will contract shingles (herpes zoster).
Symptoms of chickenpox
This viral infection produces a range of symptoms, including:
- Slight fever, runny nose, a general feeling of unwellness and other cold-like symptoms.
- A nasty rash featuring blisters that crust over to form scabs.
- Loss of appetite.
The rash can be intensely itchy and can occur over several days. Though more noticeable on the torso, the rash can also appear on the limbs, in the nose and on the inside of the mouth and throat.
These symptoms usually appear two weeks after you have been exposed to the virus, with the rash occurring over a period of three to four days. Most people recover from chickenpox without any complications, but in some cases it can cause pneumonia and an inflammation of the brain. In rare situations it can also be fatal.
What is the incubation period and how long are you infectious for?
The incubation period is the time between when you become infected with chickenpox and when you start to show symptoms. The infectious period is the time during which people with chickenpox can infect others with the illness. The timeline for the incubation period and the infectious period are shown in the table below:
|Incubation period||10 to 21 days, most commonly 14 to 16 days|
|Infectious period||From 2 days before the rash appears to a minimum of 5 days after the rash has appeared and all chickenpox blisters have crusted over|
It’s important to note that the incubation period may vary in people with suppressed immune systems, for example, children suffering from leukemia.
How do you treat chickenpox?
In most cases, the chickenpox infection is relatively mild and the patient will recover without the need for any specific treatment. However, in severe cases, your doctor may recommend treatment with an antiviral medication, though treatment needs to begin early (usually within 24 hours of the rash appearing) to be effective.
With all cases of chickenpox, there are several treatment options and remedies available to reduce the discomfort of the itch and to reduce the likelihood of any complications. These treatments include:
- Calamine lotion and a range of other creams and lotions to reduce the itching
- Promethazine [Phenergan], which is available from pharmacies and can be used to reduce the itch
- Paracetamol to lower temperature if you have a fever
- Bed rest
- Drinking extra fluids to stay hydrated
- Lukewarm baths with oatmeal or baking soda added
- Avoiding salty or citrus foods
- Using mittens or other similar clothing items to stop babies and young children from scratching the blisters
Can chickenpox be prevented?
The good news is that chickenpox can be prevented by a vaccine. Immunisation against the virus is recommended as part of Australia’s National Immunisation Program and can be achieved with one dose of the MMRV (measles-mumps-rubella-varicella) vaccine at 18 months of age. There’s also a catch-up program for kids aged 10-13 years who have not previously received the vaccine, while non-immune adolescents and adults can be protected with two doses of the varicella vaccine at least one month apart.
In addition to vaccinations, there are also a few simple ways to stop chickenpox from spreading:
- If you have chickenpox, avoid contact with other people until five days after the rash has appeared and all blisters have dried up.
- Keep infected children out of childcare and school until five days after the rash has appeared and all blisters have dried up.
- If you have chickenpox, cover your nose and mouth when sneezing or coughing and dispose of used tissues. Wash your hands regularly and don’t share food or eating utensils with other people.
- If you’re pregnant, avoid contact with chickenpox and shingles and see your doctor if you’ve come into contact with someone with one of these illnesses.
- If your child has an immune deficiency or is undergoing chemotherapy, avoid anyone with chickenpox or shingles.
It's always a good idea to keep up to date with your vaccinations, something few adult Australians do.
Can chickenpox cause other health complications?
Although most chickenpox infections are mild and patients should be able to enjoy a full recovery, severe cases can cause a range of health complications, including:
- Scarring. Chickenpox can leave distinctive pockmark scars on the skin.
- Cellulitis. This bacterial skin infection can be caused by chickenpox.
- Pneumonia. Adults infected with chickenpox can also develop pneumonia, which can be fatal.
- Encephalitis. Inflammation of the brain can also be caused by chickenpox. It’s usually mild but can sometimes be more serious.
- Death. This is very rare but it does happen.
- Complications for unborn and newborn babies. If you catch chickenpox during pregnancy, especially in the first 20 weeks, there is a risk of your baby developing congenital varicella syndrome. This can cause a range of problems for your child including scarring, eye problems, small limbs and neurological abnormalities. Your baby could also suffer from chickenpox or develop shingles in the first few years of its life.