In tropical countries, chickenpox is actually far less common, and less easily spread, than in countries with cold seasons -- and increased exposure to ultraviolet (UV) light, i.e. sunshine, appears to be the reason.
Sun Exposure May Help Stop the Spread of Chickenpox
After examining data from 25 studies on the varicella-zoster virus, which causes chickenpox, University of London researchers found a clear link between UV levels and the prevalence of chickenpox, with chickenpox rates far less common in the tropics where exposure to sunlight is common year-round.
In temperate regions, chickenpox also tends to flare up more often in the cold-weather months, when sunlight is scarce.
Writing in the Virology Journal, researchers noted:
"Chickenpox is seasonal in temperate zones, with the highest incidence seen in winter and spring. One explanation for this seasonality could be the significantly higher levels in ultra-violet radiation (UVR) of approximately 10-25-fold seen in summer in temperate zones, which could inactivate virus either in vesicular lesions or after their rupture."
The effect is likely two-fold, as not only is sunlight able to destroy many viruses directly, but it also enables your body to produce vitamin D, which gives you further anti-viral and immune-boosting benefits.
Many are not aware that prior to the advent of antibiotics about 70 years ago one of the only effective treatments for tuberculosis was sunlight. In fact there were many TB solariums that were created specifically to use sunlight to treat TB. The sun exposure produced improvement in those with TB similar to the mechanisms discussed in this article for chickenpox.
UV Light Shown to Reduce Spread of Chickenpox in Schools Over 60 Years Ago
You may have heard the advice that hanging your laundry outside to dry in the sun is one of the best ways to get your clothes truly clean and fresh, and this is true because sunlight is a natural disinfectant. Along those lines, direct sunlight exposure on your skin may also provide "disinfectant" benefits such as deactivating viruses, including chickenpox, by breaking down their cell walls.
In fact, a study published in 1949 revealed that ultraviolet radiation successfully reduced the transmission of the chickenpox virus in U.S. schools, helping to limit its spread! And some air purification and water treatment systems currently use ultraviolet light to eliminate airborne or waterborne pathogens.
Sun Exposure Increases Your Vitamin D -- Another Virus Fighter
The other reason why people in the tropics may be less likely to catch and spread the chickenpox is because their year-round sun exposure allows them to maintain healthier levels of vitamin D. In cold-weather climates, on the other hand, vitamin D deficiency is an epidemic.
If you're vitamin-D-deficient, and many are, your immune system will not activate to do its job. Contrary to common belief, vitamin D does much more than just support healthy bones; vitamin D functions in many different tissues and affects a large number of different diseases and health conditions. So far, scientists have found about 3,000 genes that are regulated by vitamin D – that's more than 1 in every 10 genes in your entire genome!
Just one example of an important function that vitamin D up-regulates is your ability to fight infections, including the flu. At least five studies show an inverse association between lower respiratory tract infections and vitamin D levels. That is, the higher your vitamin D level, the lower your risk of contracting colds, flu, and other respiratory tract infections. It makes sense, therefore, that this would extend to other viral infections like chickenpox as well.
As I've stated before, your body was designed to benefit from sunlight exposure. Given adequate levels, your skin is able to produce a wide range of infection fighting substances, including defensins, cathelicidin, and the lesser known cholesterol sulfate. As Dr. Stephanie Seneff, a senior scientist at MIT, explained:
"I think of the skin as a battery – or solar panel you might say – taking in the sun's energy and saving it in the form of the sulfate molecule storing the energy in the sun … I have a lot of thoughts about what sulfate does. One thing I'm quite sure of is that cholesterol sulfate is highly protective against bacterial and virus invasions. That's why sun exposure protects you from infection. It strengthens your immune system. That cholesterol sulfate is incredibly important to immunity."
The important factor when it comes to vitamin D is your serum level, which should ideally be between 50-70 ng/ml year-round. For more tips on how to optimize your vitamin D levels -- ideally through sun exposure or the use of a safe tanning bed -- see this past article How to Get Your Vitamin D Levels to a Healthy Range. However, keep in mind that for children, becoming infected with the chickenpox virus is not necessarily something that should be avoided, especially by way of vaccination, as natural exposure provides subsequent, and safe, long-lasting immunity.
Sunlight Might Not Be Best Once You Have Active Pox Lesions
Although it is wonderful to have confirmation of the power of vitamin D in the treatment of infectious diseases that have typically been fought with vaccines, there is one caution about using sunlight as therapy for someone with active lesions.
Actually this is true for any open wound on the skin regardless if it is caused by a viral infection or a traumatic wound. Sunlight will tend to cause the wound to scar, so it is probably best to actually avoid sunlight if you have pox lesions. However, anyone exposed to the virus without lesions could still use sunshine as a therapy. So if you or your child has active pox lesions it would likely be better to take oral vitamin D at the rate of 8,000 units a day for a typical adult and proportionately lower based on weight for a child.
Is Natural Exposure to Chickenpox Preferable to Vaccination?
As is true with many new and potentially unnecessary medical interventions used on a widespread basis, there are often unintended, adverse consequences. The chickenpox (varicella) vaccine is a perfect example.
Chickenpox is highly contagious but typically produces a mild disease characterized by small round lesions on your skin that cause intense itching. Chickenpox lasts for two to three weeks, and recovery leaves a child with long-lasting immunity. Further, some healthy children may have only minimal symptoms (such as a low fever and headache) without manifestation of blisters, indistinguishable from a mild case of the flu.
So, even in the vast majority of children who do NOT get the chickenpox vaccine and who have negative or unknown chickenpox histories, they wind up immune to chickenpox anyway. In fact, researchers have concluded that most 10-year-old children with negative or unknown histories of chickenpox are already immune!
Up to 20 percent of adults who get chickenpox develop severe complications such as pneumonia, secondary bacterial infections, and brain inflammation (which is reported in less than one percent of children who get chickenpox). Most children and adults who develop these serious complications have compromised immune systems or other health problems. Still, it is because chickenpox can be serious in adults that it is often regarded as preferable to get it as a child, as opposed to later in adulthood. Using a vaccination to prevent chickenpox in childhood is proving to be problematic, however, for several reasons:
- Chickenpox vaccine provides only temporary immunity, not the longer lasting immunity you get when you recover naturally from chickenpox.
- The vaccine is not 100 percent effective. When the chickenpox vaccine was licensed for public use in 1995, the Food and Drug Administration (FDA) estimated it was 70 to 90 percent effective in preventing disease. The Centers for Disease Control (CDC) later reported, "The effectiveness of the vaccine is 44 percent against disease of any severity and 86 percent against moderate or severe disease."
But the vaccine may be LESS effective than that—around 40 percent—according to an investigation of a chickenpox outbreak among 23 children at a New Hampshire daycare center. The outbreak began with a child who had already been vaccinated.
- The chickenpox vaccine can cause serious injury and death. Four percent of reported adverse events (about 1 in 33,000 doses) after chickenpox vaccination involve serious health problems such as shock, encephalitis (brain inflammation), and thrombocytopenia (a blood disorder). At least 14 deaths have been reported. In fact, there are at least two dozen documented adverse effects of chickenpox vaccination in the medical literature.
Another Unintended Consequence of Chickenpox Vaccination
After contracting and recovering from chickenpox (usually as a child), your natural immunity gets asymptomatically "boosted" by coming into contact with infected children, who are recovering from chickenpox. This natural "boosting" of natural immunity to the chickenpox virus helps protect you from getting shingles -- a painful and potentially serious disease -- later in life.
In other words, shingles can be prevented by ordinary contact, such as receiving a hug from a grandchild who is getting or recovering from the chickenpox. But with the advent of the chickenpox vaccine, there is less chickenpox around to provide that natural immune boost for children AND adults. So, as chickenpox rates have declined, shingles rates have begun to rise, and there is mounting evidence that an epidemic of shingles is developing in America from the mass, mandatory use of the chickenpox vaccine by all children.
For more information on varicella and chickenpox vaccine, see the National Vaccine Information Center’s new Chickenpox page.
If Your Child Comes Down With Chickenpox …
First, don't panic. Remember this is a common illness that is typically mild if your child is otherwise healthy, and it should resolve in two to three weeks without complications or medical treatment. During this time, a cool or lukewarm bath with baking soda added may help to relieve symptoms, such as itching. Be sure your child does not scratch any sores, as this can lead to scarring or infection (putting gloves or socks on your child's hands may help with this).
Also, be sure you do NOT give aspirin to your child, as this is associated with the development of Reye's syndrome, which can cause brain damage and death. Also avoid ibuprofen, which is linked to more severe secondary infections in children with chickenpox.