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There have been no cases of the rare variant COVID-19 type of chickenpox found in Australia in the United States yet, the CDC has announced.
“This [vaccine] has not been shown to be the cause of these rare infection complications,” said the CDC.
In recent days, a child in California had to have surgery after a case of a rare variant of chickenpox was identified.
In Australia, the vaccine has caused 86 cases and one death. The Australian government says it has the go-ahead to import the vaccine.
Who is at risk?
The CDC, which oversees the US vaccination schedule, said that as a “low risk” population, parents in the US should have their children vaccinated.
Chickenpox can lead to rashes, blisters, and other symptoms, mostly found on the face and back of the neck. Symptoms occur between six and 10 days after infection, which is why the vaccine is called “chickenpox”.
There are a number of different types of chickenpox, including the three variants listed here, and each has different symptoms. The viruses can live on a skin surface for two weeks, potentially infecting a new host, and so the two-week vaccination window has shrunk slightly in recent years.
What are the risks of infection?
Eighty two (or 89%) of the 86 cases in Australia occurred in children aged between six and eight years old, and many of those cases ended in hospitalisation.
One child needed surgery to remove pus and pus membrane fragments removed from a minor facial blister. It is the same infection that the Australian child contracted abroad.
The cold, wet weather in the US currently does not appear to be helpful in containing the illness.
Chickenpox is uncommon
About 170,000 cases of chickenpox are reported in the US every year. This is comparable to the number of reported cases in Australia.
The number of cases has fallen significantly in recent years, from about 830,000 in 1998 to 30,000 cases in 2016.
How is chickenpox caught?
The disease is caused by a virus (proportionalally, the genus S flukia). Once it infects a person, the virus multiplies in the body causing a blister-like infection.
What causes chickenpox?
The infection develops into a red rash all over the body. Mouth blisters form as the virus penetrates the skin, and fill with pus and blisters, often on the nose and throat.
There are two types of chickenpox. The herpes simplex types cause acute disease with high redness in the first few days after infection. In some cases, adults as well as children may have mild allergic reactions to the infection.
The varicella zoster type causes a more common disease in adults. It is caused by a live virus that causes serious injury or death in several percentage of people who contract it.
Chickenpox is contagious from a day or two after an infection and though it is usually mild, one in five cases can develop septicemia, a serious blood infection.
Can you still catch chickenpox?
The CDC says that not all people become seriously ill and the risk of complications from chickenpox has been reduced due to vaccination.
“Vaccination has been shown to reduce the number of cases, but vaccines can’t offer 100% protection,” the agency said.
The CDC recommends that everyone aged six months to 65 years receive two doses of vaccine at two years and four years old, depending on their age.
The Government of Australia also recommends that children between six months and four years get the chickenpox vaccine, in addition to measles, mumps and rubella (MMR) vaccines.
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