this is funny (from wikipedia):
Pox parties
A "pox party" is a party held by parents for the purpose of infecting their children with childhood diseases. Similar ideas have applied to other diseases, e.g. measles, but are now discouraged by doctors and health services. The rationale behind such parties is that guests exposed to the varicella virus will contract the disease and develop strong and persistent immunity, at an age before disaster is likely particularly from chickenpox or rubella. Such parties are now less common in mainstream communities. They are essentially a revival of primitive, pre-vaccination attempts at inoculation.
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not so funny:
Effects
Child with varicella disease.
Chickenpox has a two-week incubation period and is highly contagious by air transmission two days before symptoms appear. Therefore, chickenpox spreads quickly through schools and other places of close contact. Once someone has been infected with the disease, they usually develop protective immunity for life. It is fairly rare to get the chickenpox multiple times, but it is possible for people with irregular immune systems. As the disease is more severe if contracted by an adult, parents have been known to ensure their children become infected before adulthood.
The disease can be fatal. Pregnant women and those with immune system depression are more at risk. Death is usually from varicella pneumonia. In the US, 55 percent of chickenpox deaths were in the over-20 age group. Pregnant women not known to be immune and who come into contact with chickenpox should contact their doctor immediately, as the virus can cause serious problems for the fetus. In the UK Varicella antibodies are measured as part of the routine of antenatal care, and by 2005 all NHS healthcare personnel had determined their immunity and been immunised if they were non-immune and have direct patient contact.
Later in life, viruses remaining in the nerves can develop into the painful disease shingles, particularly in people with compromised immune systems, such as the elderly, and perhaps even those suffering sunburn. Some of these will develop zoster-associated pain or post-herpetic neuralgia, described usually as "horrible" or "excruciating". A chickenpox vaccine has been available since 1995, and is now required in some countries for children to be admitted into elementary school. In addition, effective medications (e.g. aciclovir) are available to treat chickenpox in healthy and immunocompromised persons.
Symptomatic treatment—calamine lotion to ease itching and paracetamol to reduce fever—is widely used. Aspirin is contraindicated in children, as it can lead to Reye's syndrome.