Varicella vaccine
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 is recommended. In the United States two doses are recommended starting at twelve to fifteen months of age. As of 2012 most European countries either recommend it for all children or just those at high risk, but not all countries provide the vaccine due to its cost.
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.
The chickenpox vaccine first became commercially available in 1984. It is on the World Health Organization's List of Essential Medicines, the most effective and safe medicines needed in a health system. In the United States it costs between 100 and 200 USD.
Pertussis vaccine
Pertussis vaccine is a vaccine that protects against whooping cough (pertussis). There are two main types: whole-cell vaccines and acellular vaccines. The whole-cell vaccine is about 78% effective while the acellular vaccine is 71–85% effective. The effectiveness of the vaccines appears to decrease by between 2 and 10% per year after vaccination with a more rapid decrease with the acellular vaccines. Vaccinating the mother during pregnancy may protect the baby. The vaccine is estimated to have saved over 500,000 lives in 2002.
The World Health Organization and Center for Disease Control and Prevention recommend all children be vaccinated for pertussis and that it be included in routine vaccinations. This includes for people who have HIV/AIDS. Three doses starting at six weeks of age are typically recommended in young children. Additional doses may be given to older children and adults. The vaccine is only available in combination with tetanus and diphtheria vaccines.
The acellular vaccines are more commonly used in the developed world due to fewer adverse effects. Between 10 and 50% of people given the whole-cell vaccines develop redness at the injection site or fever. Febrile seizures and long periods of crying occur in less than 1% of people. With the acellular vaccines a brief period of non-serious swelling of the arm may occur. Side effects with both types of vaccines, but especially the whole-cell vaccine, are less common the younger the child. The whole-cell vaccines should not be used after seven years of age. Serious long term neurological problems are not associated with either type.
The pertussis vaccine was developed in 1926. It is on the World Health Organization's List of Essential Medicines, the most effective and safe medicines needed in a health system. A version that also includes tetanus, diphtheria, polio, and Hib vaccine is available wholesale in the developing world at a cost of 15.41 USD per dose as of 2014.