Measles outbreaks may be tied to parents’ choice not to vaccinate

When it comes to immunisations, rumours and worried whispers are a mainstay is some parenting circles – from concerned conversations on soccer field sidelines to pointed posts on message boards and blogs. And once a seed of doubt is planted – even if the science or the source behind it may be unreliable or unsubstantiated – it’s hard for perplexed parents to get it out of their minds.

As more and more mums and dads opt not to have their kids vaccinated because of their personal or religious beliefs, health officials this year are seeing the highest rate of measles cases in the United States in more than a decade (since 1996).

The Centers for Disease Control and Prevention (CDC) says 131 people were infected with measles (also called rubella) in 15 states from January to July this year alone – and 2008 isn’t even over. That’s more than twice the number of cases (63, on average, each year) from 2000 to 2007.

Looking at who’s getting the disease and from where, the CDC says:

• 91% of those infected hadn’t been vaccinated or their vaccination status was unknown
• 89% of the cases were linked to people coming from or travelling to other countries, especially those in Europe
• 76% were under 20 years old

Before the vaccine was introduced in the mid-1960s, measles caused about 450 deaths and 4,000 cases of encephalitis (inflammation of the brain) each year. An epidemic of the disease did break out in the United States between 1989 and 1991 when falling rates of immunisations among preschoolers led to a sharp increase in the number of measles cases, deaths, and children with permanent measles-related brain damage.

But after about 30 years of an active vaccination program, the disease was virtually wiped out here in 2000. The United Kingdom also thought it had gotten rid of measles 14 years ago, but it’s now widespread again since immunisation rates there have dropped – a worrisome situation the United States may soon be facing, too.

Measles still affects 20 million people worldwide every year. And, despite the common perception that the disease just causes a nasty rash, measles can actually be very serious and even deadly – globally, it killed 311,000 kids under age 5 in 2005 alone.

More on Measles

Measles is a viral infection that can spread easily through the air by sneezing and coughing. The illness causes a total-body skin rash and flu-like symptoms, including a fever, cough, and runny nose.

In some cases, the infection can lead to other health problems like:

• croup
• bronchitis
• bronchiolitis
• pneumonia
• conjunctivitis (pinkeye)
• ear infections
• myocarditis (inflammation of the heart muscle)
• encephalitis

A concern weighing on many parents’ minds when it comes to vaccines is autism and the MMR vaccine that protects against measles, mumps, and rubella (German measles). But study after study has found no scientific evidence that autism is caused by any single vaccine, combination vaccines (like the MMR vaccine), or the mercury-containing preservative thimerosal, which was once widely used in many childhood vaccines (including MMR) but has since been eliminated.

The controversial 1998 study that originally started the debate by suggesting a link between the MMR vaccine and autism was retracted – or thrown out – in 2004, long after it had been rejected by many major health organisations. But the study and the attention it received influenced parents worldwide and contributed to a decrease in immunisation rates.

Despite the lack of scientific evidence that it causes any harm, manufacturers began removing thimerosal from kids’ vaccines in 1999 to reduce childhood exposure to mercury and other heavy metals. Now, the flu vaccine is the only one used in kids 2 and under that contains any of the preservative. Although some of the flu vaccines do have thimerosal in them, most of those available for children have only trace amounts and are technically considered thimerosal-free.

The only way to protect your kids from getting measles is immunisation. Children should get the MMR vaccine at 12 to 15 months and then the follow-up booster shot between 4 and 6 years. And if you’re planning to take a trip abroad with your baby in tow, infant’s ages 6 to 11 months should get the MMR vaccine, too.

The fact is, a series of simple shots given from infancy to the teen years can fend off many major illnesses in millions of kids. Yet, a recent CDC study found that more than a quarter of young US kids (ages 18 months to 3 years) aren’t getting their vaccines on time.

Some parents may hesitate to have their kids vaccinated because they’re worried about the risks and the possibility of serious reactions. Although some vaccines may cause mild reactions – like temporary fever and soreness around the shot site – serious reactions are very rare. All in all, the risks of serious reactions to vaccinations are extremely small compared with the health risks associated with the often-serious diseases they’re intended to prevent.

Even though you may wonder why your children need immunisations if many of the diseases they protect against are no longer prevalent in the United States, infectious diseases that are rare or nonexistent here (because of immunisation programs like those for measles and polio) are still huge problems in other parts of the world.

That means if immunisation rates are allowed to drop among U.S. children, the spark for a major epidemic would be only an airplane flight away – when a disease could be introduced by just one unimmunised person (either an American travelling overseas or someone coming into the United States). Case in point: One 12-year-old boy from Japan who unknowingly had measles came to the United States for the August 2007 Little League World Series and passed the infection on to others.

An individual child’s chance of catching a disease is low if everyone else is immunised. But if the number of unimmunised children in a population grows, the risk of sparking an epidemic increases dramatically.

Although it’s natural to want to ensure that everything you do is in your youngsters’ very best interests, when parents don’t have their kids vaccinated, for whatever reason, it can affect everyone. That means even if you’ve made the decision to not vaccinate your children, it’s not just your kids who could be at risk of catching certain preventable diseases – they could pass them on to other children, too (like babies who are too young to be vaccinated).

That why it’s only safe to stop vaccinations for a particular disease when that disease has been totally wiped out worldwide, as in the case of smallpox.

To make sure your kids get all of the immunisations they need on time at every age:

• Schedule and keep all of your family’s regular checkups.
• Get routine vaccinations on schedule as children grow – not just in the infant and toddler years, when most vaccines are given. Routine vaccines and boosters are also recommended between the ages of 4 and 6, 11 and 12, and then again before teens enter college.
• Find out when your kids can get any vaccine that’s in short supply.
• Ask your doctor about any new vaccines. Boosters and vaccines are added to the childhood immunisation schedule all the time – like the now-recommended chickenpox booster for 4- to 6-year-olds and the human papillomavirus (HPV) vaccine for 11- to 12-year-old girls.
• Never skip a dose in a vaccine series. Kids don’t have adequate protection if they don’t get all of the recommended doses for each series at the right time.
• Ask your doctor if you or your kids need any catch-up immunisations or boosters to ensure that your protection is up to date, especially if you’re planning to travel overseas.

And before you jump to any conclusions or accept any medically related message you see, hear, or read about – no matter how reliable or believable the source may seem – talk to your doctor first. Discuss the information you’ve encountered, ask what it really means, and get all of the facts before making a decision to delay or skip an immunisation – a choice that could affect not only your kids’ health but also that of other children.

(Source: Morbidity and Mortality Weekly Report: Nemours Foundation: September 2008)