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What are chickenpox and shingles?
Chickenpox is a highly contagious rash caused by varicella zoster virus. Chickenpox infection generally confers lifelong immunity. You may develop an infection without symptoms, and this also generally confers immunity. It is normally a very mild rash illness and only very rarely causes serious complications; children with eczema are not at increased risk of complications. Death is very rare. However, in otherwise healthy adults, the chickenpox complication rate is 15-25 times higher and the death rate is 20 times higher.
After a chickenpox infection, the virus hibernates in a nerve. In times of stress or immune suppression, the virus may reawaken and cause shingles. (You cannot catch shingles. You can catch chickenpox, which might later develop into shingles if your immunity is low.) Shingles is associated with 4-5 times higher complication rate and medical costs than chickenpox.
Chickenpox vaccines are typically given twice in early childhood in North America, Germany, and Australia. The shingles vaccine is given to older adults. Most of the developed world does not use these vaccines.
How can I prevent or treat chickenpox and shingles in my child?
Because chickenpox is mild in childhood but potentially serious in adulthood, many people choose to intentionally expose their child and get it over with in childhood. If you choose to do this, avoid people with immune suppression, pregnant women, and infants during the contagious period. Do not mail infectious material and do not intentionally expose others without their knowledge and consent.
It takes about 10-21 days after exposure for the first spots to appear. Chickenpox is contagious from about 2 days before the spots appear to as much as 7 days later, when the spots are all crusted over. A fever often occurs for one or two days before the first spots appear. To prevent infection, avoid children with chickenpox, fever, or unidentified rash.
The vaccine contains a live virus. There have been several reports of people developing chickenpox with vaccine-strain virus shortly after a close contact was vaccinated. To prevent infection, avoid people who have recently been vaccinated against chickenpox or shingles.
Exposure to chickenpox acts as a natural “booster shot” to protect adults against shingles. If you or your child have had chickenpox or the vaccine, prevent shingles by seeking exposure to chickenpox.
You can treat chickenpox with calamine lotion and daily baths with soap and water. Do not use aspirin, Tylenol, or Benadryl (diphenhydramine), and do not use lotions that have diphenhydramine in them. Use ibuprofen to lower a fever only if the fever is over 106°F (41.1°C). You should generally not take steroids during a chickenpox infection; if your child is on steroids, talk to your doctor about whether to stop the steroids until he recovers. Use anti-infectives such as silver nitrate and essential oils on the spots to prevent bacterial infection. If he develops a secondary fever after the spots have appeared, seek immediate medical attention.
How effective are the vaccines at preventing asymptomatic carriage?
Vaccinated people can have asymptomatic infections with both vaccine-strain and wild-type varicella viruses, and have proven to be contagious during that time. However, whether the vaccine reduces, increases, or has no effect on the degree or duration of asymptomatic carriage is unknown.
How effective are the vaccines?
The chickenpox vaccine is more effective when fewer children receive it because natural exposure to chickenpox boosts immunity, so vaccinated children get a natural “booster shot” from their unvaccinated friends. However, in communities where chickenpox vaccination is widespread, effectiveness drops to very low levels within a few years. A few studies found it to be completely ineffective or even reverse-effective (increased the chickenpox rates). When the vaccine fails, people tend to get chickenpox at an older age, when it is more dangerous.
Since exposure to chickenpox boosts immunity and prevents shingles, researchers predicted that widespread chickenpox vaccination would increase shingles rates. They were proven right by numerous studies in many countries using the vaccine. Because shingles is much more dangerous than chickenpox, the vaccine results in overall increased complication rate and medical costs, so the vaccine is neither effective nor cost-effective. Furthermore, the addition of new booster shots and shingles vaccines to fix this problem is not cost-effective and is associated with a higher complication rate than if children had been permitted to get chickenpox naturally.
The shingles vaccine may be as much as 51% effective and last 1 month to 5 years, necessitating numerous booster shots. It is less effective in people over 70 and completely ineffective in people over 80. Exposure to a child with chickenpox would be much more effective and much safer.
Are there other infectious diseases related to chickenpox/shingles vaccination?
MMR vaccination indirectly resulted in increased severity of chickenpox. This increased severity is part of why the CDC recommends chickenpox vaccination. However, most of Europe still agrees that the risks of chickenpox vaccination far outweigh any possible benefit.
What are the risks of the vaccines?
Adverse reactions to the chickenpox vaccine are at least equal to, and some research shows is greater than, adverse reactions to chickenpox infection. The combination MMR and chickenpox vaccine causes a higher fever and more seizures than MMR and chickenpox vaccines given separately. Chickenpox vaccination increases the risks of shingles, multiple sclerosis, heart disease and heart attacks, and brain tumors.
The shingles vaccine is associated with a very high rate of adverse reactions, especially in the oldest groups. The vaccine also causes severe autoimmune reactions, including a doubled risk of arthritis and tripled risk of alopecia.
So what’s the bottom line?
Chickenpox is very mild in childhood and has some long-term health benefits (e.g., decreased risk of multiple sclerosis, heart disease/heart attack, brain tumors), but poses much greater risk and fewer benefits in adulthood. Vaccination may merely delay chickenpox infection until adulthood, when it has considerably more risk. Natural chickenpox infection and repeated exposure to chickenpox decreases the risk of shingles. Conversely, chickenpox vaccination has very low effectiveness against chickenpox, increases the risk of shingles, and results in more severe shingles occurring at younger ages. Shingles is much more dangerous than chickenpox. The shingles vaccine does not appear to be very effective, but research is very limited; it is not effective in the oldest groups and is not yet approved for people under 50. Both vaccines are associated with some serious adverse effects, especially the shingles vaccine.