Varicella vaccine, also known as chickenpox vaccine, is a vaccine that protects against chickenpox. One dose of vaccine prevents 95% of moderate disease and 100% of severe disease. Two doses of vaccine are more effective than one. If given to those who are not immune within five days of exposure to chickenpox it prevents most cases of disease. Vaccinating a large portion of the population also protects those who are not vaccinated. It is given by injection just under the skin.
The World Health Organization (WHO) recommends routine vaccination only if a country can keep more than 80% of people vaccinated. If only 20% to 80% of people are vaccinated it is possible that more people will get the disease at an older age and outcomes overall may worsen. Either one or two doses of the vaccine are recommended. In the United States two doses are recommended starting at twelve to fifteen months of age. As of 2017, twenty-three countries recommend all non-medically exempt children receive the vaccine, nine recommend it only for high risk groups, three additional countries recommend use in only parts of the country, while other countries make no recommendation. Not all countries provide the vaccine due to its cost.
Chickenpox, also known as varicella, is a highly contagious disease caused by the initial infection with varicella zoster virus. The disease results in a characteristic skin rash that forms small, itchy blisters, which eventually scab over. It usually starts on the chest, back, and face. It then spreads to the rest of the body. The rash and other symptoms, such as fever, tiredness, and headaches, usually last five to seven days. Complications may occasionally include pneumonia, inflammation of the brain, and bacterial skin infections. The disease is often more severe in adults than in children.
Minor side effects may include pain at the site of injection, fever, and rash. Severe side effects are rare and occur mostly in those with poor immune function. Its use in people with HIV/AIDS should be done with care. It is not recommended during pregnancy; however, the few times it has been given during pregnancy no problems resulted. The vaccine is available either by itself or along with the MMR vaccine, in a version known as the MMRV vaccine. It is made from weakened virus.
Another vaccine, known as zoster vaccine, is simply a larger-than-normal dose of the same vaccine used against chickenpox, and is used in older adults to reduce the risk of shingles and postherpetic neuralgia, which are caused by the same virus. The live zoster vaccine is recommended for adults aged 60 years and older. A recombinant zoster vaccine is recommended for adults aged 50 years and older.
A zoster vaccine is a vaccine that reduces the incidence of herpes zoster, a disease caused by reactivation of the varicella zoster virus, which is also responsible for chickenpox. Shingles provokes a painful rash with blisters, and can be followed by chronic pain, as well as other complications. Older people are more often affected, as are people with weakened immune systems. Both shingles and postherpetic neuralgia can be prevented by vaccination.
Journal of Vaccines & Vaccination