Friday, June 12, 2009

Health tip

The Risks of Skipping Kids' Vaccines
The pros and cons of 'opting out.'
By Lisa Farino for MSN Health & Fitness
Medically Reviewed by: Ken Haller, M.D

Before the days of vaccinations and antibiotics, early childhood used to be an especially risky time. Today, as many deadly or permanently debilitating diseases slip into the realm of forgotten history, many parents seem more concerned about the potential dangers of vaccinations than about the diseases themselves.

In previous decades, the biggest concern was vaccination-related mercury exposure from the preservative thimerosal, which has since been removed from the pediatric version of most vaccinations.

Despite this change, some parents remain concerned that vaccinations are somehow connected to autism and other neurological problems, although the CDC insists there’s no scientific evidence to support this claim.

Fears of autism and immune system 'overload'

Concerns over vaccinations have not been limited to thimerosal, but have also included the MMR vaccine. “The Lancet published one study in the late 1990s linking the MMR vaccine to autism,” explains Dr. Andrew Kroger, a Medical Officer for the CDC’s Immunization Services Division. “That study was later found to be seriously flawed and The Lancet ultimately published a retraction.”

In addition, some parents are concerned that the sheer number and frequency of vaccinations, especially in the first year of life, is somehow overwhelming the immune system. “Even at a very young age, the body has tens of millions of lymphocytes [a type of white blood cell] to develop immunity to many different foreign bodies simultaneously,” explains Dr. Kroger. “There is no way the immune system can be overloaded. In fact, when we look at people who’ve received vaccinations, they have lower rates of non-vaccine-preventable diseases, suggesting that their immune systems are at least as strong as those of people who haven’t been vaccinated.”

'Opting out' of vaccinations

Over the years, public outcry from a quite small but vocal percentage of parents has lead many states to create a relatively easy path for parents to 'opt out' of required childhood vaccinations based on personal beliefs. As this trend has grown (as of early 2006, 19 states allowed for some form of opting out due to non-religious personal belief), so has the number of children who aren’t receiving all the vaccinations recommended by the CDC.

Nationwide, the percentage of parents who are opting out of some or all of the required vaccinations is quite low, with nonmedical exemption rates lower than 3 percent, even in states that offer an easy way to opt out due to personal beliefs. However, the exemptors aren’t evenly distributed throughout the country. Instead, public health researchers are finding that exemptors tend to concentrate in particular geographic pockets.

According to a 2006 article in The Journal of the American Medical Association, exemption rates of 15 to 18 percent have been found in the affluent, progressive communities of Ashland, Oregon and Vashon Island, Washington. And in California, where the statewide exemption rate is only 1.5 percent, some counties had exemption rates of 10 to 19 percent among their kindergarteners.

The problems with opting out

These clusters of exemptors have public health officials worried because high enough rates of non-vaccination can lead to a resurgence of vaccine-preventable diseases. “The more contagious a disease is, the higher the vaccination rate needs to be to prevent an outbreak,” says Dr. Kroger. For instance, if the rate of vaccination for a highly contagious disease like the measles falls below 90 to 95 percent, we could see the disease become endemic once again in the United States. Even for less contagious diseases, a vaccination rate of 80 to 85 percent or more is needed to prevent the disease from taking hold again.

The problem is, there aren’t just parents who are opting out for reasons of personal or religious beliefs. There are also children who are unable to be vaccinated for medical reasons. For instance, kids who have compromised immune systems need to avoid certain “live” vaccinations, and kids who have life-threatening allergies to an ingredient in a vaccine may need to avoid it as well.

That means that belief-based opt-out rates don’t need to be that high before they can combine with medical opt-out rates to push non-vaccination rates into the critical zone. It also means that belief-based exemptors may be putting the medical-based exemptors at risk.

Making an informed decision about vaccinations

If your inclination is to get all the vaccinations the CDC recommends, by all means do so. These vaccinations are safe, serious reactions are rare, and a pre-vaccination consultation with a pediatrician will ensure that your child does not have any contraindications for any of the vaccinations. The CDC offers a complete schedule for all the vaccines recommended for children up to one year old.

If, however, you are tempted to delay or forgo any vaccinations for your children, it’s critical that you educate yourself about the diseases those vaccinations are intended to prevent. As an increasing number of parents are delaying or forgoing certain vaccinations, it’s no longer possible to simply assume these diseases will remain so rare that they are not a threat.

Even more so, the consequences of many of these diseases can be quite serious. For instance, did you know that the fatality rate from diphtheria for children under the age of 5 is up to 20 percent? Or that roughly 25 percent of post-pubescent boys will experience some degree of permanent testicular shrinkage following a bout of the mumps?

And for a disease like tetanus—which causes gruesome muscle spasms and seizures and has a greater than 10% fatality rate—the risk of contracting has absolutely nothing to do with whether or not other children are vaccinated. That’s because the disease is spread solely by spores found in soil and dirt, rather than from person to person.

The pros and cons of vaccination

In weighing the pros and cons of vaccination, there’s more to consider than just the absolute risks of the disease. There’s also the issue of whether or not you want your child to suffer through a preventable illness and whether or not you have the luxury of taking enough time off of work to care for a sick child.

Take chicken pox, for example. If you’re old enough to be considering vaccinations for your youngster, chances are you are old enough to remember the chicken pox as a rather mild childhood illness, provided that you contracted it at a young age. In fact, only 4 in 100,000 young kids will die from chicken pox. Even if those are risks you’re willing to live with, you need to ask yourself if you want your child to suffer through the disease and if you or your spouse can afford to take a week or two off of work to care for your sick child.

The vaccination guide that follows details the 14 diseases children are vaccinated against during the first 12 months of life. It includes an overview of what the disease is, what the most serious complications are, and who’s most at risk.

Not included are vaccinations that can’t be given until children are older, such as Meningococcal Polysaccharide Vaccine (typically begun when a child is 2 years old) and Human Papillomavirus (HPV, typically given to girls aged 9 and up).

For further information about vaccines, talk with your health-care provider, or visit the website of the CDC or that of the National Vaccine Information Center.

Ken Haller, MD, is a board-certified pediatrician and associate professor of pediatrics at Saint Louis University School of Medicine in St. Louis, MO.