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Chickenpox is a highly contagious infectious disease. It is characterised by a fever and small, red, itchy blisters on the face and body. While chickenpox is common and harmless to most people, it may have an adverse impact on those with weakened immune system, pregnant women and babies. It can be prevented through vaccination.

What is chickenpox?

Chickenpox is a highly contagious infectious disease caused by the varicella-zoster virus (VZV). Anyone can get chickenpox. However, while it is more common in children, its effects are often more severe in adults than in children. Chickenpox is common and harmless to most people.

But it may have an adverse impact on:

  • those whose immune systems are impaired such as new-born infants,

  • those undergoing chemotherapy for cancer,

  • people with AIDS,

  • those taking steroids.

Chickenpox can also give rise to more severe problems in pregnant women, causing stillbirths or birth defects, and can spread to their babies during childbirth.

However, it be prevented through vaccination.


What are the symptoms and signs of chickenpox?

Typical symptoms are fever, together with red spots on the body and face. The spots appear over a few days and progress from being red spots to blisters which eventually burst, dry up and form crusts before healing. These spots are usually itchy and may leave scars when scratched.


What are the possible complications of chickenpox?

Possible complications of a chickenpox infection include:

· Skin infection such as sores becoming more red, swollen, or tender.

· Dehydration due to frequent vomiting or refusal to drink. The person will pass urine less often, feel drowsy, have a dry mouth and lips, and be very thirsty.

· Brain damage from encephalitis, which may present with a severe headache, stiff neck and back, confusion, irritability, or excessive drowsiness.

· Pneumonia characterised by coughing, wheezing, breathing difficulty, and chest pain.

· Arthritis characterised by joint pain, stiffness, and swelling.

Complications from chickenpox can occur, but they are not common in healthy individuals. People at risk of serious complications are those with weakened immune system, pregnant women, infants etc. Some patients with serious complications can be so sick that they need to be hospitalized. Chickenpox can even cause death. Thanks to the vaccination program, death is very rare nowadays.


How does the disease spread?

Varicella-zoster virus spreads from person to person through direct contact or by droplets from an infected person when he/she coughs or sneezes. It can also spread indirectly through articles freshly soiled by droplets or fluid from the blisters of an infected person. The scabs themselves are not considered infectious.

One can get chickenpox within 10–21 days after contact with an infected person. An infected person is usually infectious one or two days before the rash appears until about a week later when the spots have stopped forming and have dried.

Once you have had chickenpox, you are immune to the disease and are very unlikely to catch it again. The virus particles remain dormant in your nervous system. However, it can at a later stage cause shingles.


How to treat chickenpox?

Treatment is directed at reducing the itch and discomfort. For example, dabbing the spots with calamine lotion may also help relieve the itching.

Important to know that children with chickenpox should not receive aspirin. It’s due to the possibility of causing a complication called Reye’s syndrome, which is a very serious illness that can cause liver and brain damage.

There are also antiviral medications that can be used to treat chickenpox. These are usually most effective when taken within the first 24 hours of developing the illness. They reduce the severity and duration of the disease, as well as reduce the likelihood of complications. Most children do not need them. Most adults would benefit from them if taken early enough, especially those who have impaired immunity as they are more susceptible to severe chickenpox.


How to prevent chickenpox?

Chickenpox can be prevented through vaccination. The vaccine is safe and effective in protecting those who have never had chickenpox.

For children, two doses of varicella vaccinations are recommended at 12 and 15 months. Older children, adolescents and adults who are previously unvaccinated are also recommended to get the vaccine if they have not been previously vaccinated against varicella.

Adults, such as non-immune healthcare workers, and those who live or work in conditions where transmission can easily occur, such as foreign workers and college students, are advised to have the chickenpox vaccination. In the latter case, outbreaks can result very quickly among non-immune adults who are more susceptible to severe chickenpox. Non-pregnant women of child-bearing age who are not immune should also be vaccinated.

Two doses of chickenpox vaccine are more than 90% effective at preventing chickenpox. The vaccine is expected to provide lifelong immunity. Some people who are vaccinated may still get the disease. However, the symptoms are usually milder with fewer rashes, mild or no fever.



1. Chickenpox: Symptoms and Treatment Options,

2. About chickenpox,

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