When my 22-month-old daughter, Manya, landed in the emergency room at Fletcher Allen recently, after six days of fevers that occasionally spiked above 105º F, my wife and I feared the worst.
Thankfully, Manya's illness eventually turned out to be roseola, a relatively harmless virus. But in diagnosing her, the ER pediatric team had to rule out several very scary infectious diseases. They immediately checked to see if our daughter was current on all of her vaccines — she is.
The vaccine question took on new urgency because of a case of measles had recently been confirmed in southeastern Vermont, the first in the state in 10 years. The disease resurfaced at a time when fewer Vermont parents are vaccinating their children — a nationwide trend that alarms many public-health officials, who fear a resurgence of preventable childhood diseases, such as polio, that were once considered eradicated from this country.
Consider measles. About 92 percent of Vermont children receive the measles-mumps-rubella (MMR) vaccine by age 3. That rate seems like it would be sufficient to keep the disease at bay. However, state infectious disease experts warn that it may not be high enough to prevent sporadic outbreaks of measles, which is highly contagious and still common in much of the developing world.
Why isn't 92 percent high enough? For starters, because no vaccine is 100 percent effective. Some people who are vaccinated still develop the disease. Moreover, some children, including babies younger than 12 months old and kids with compromised immune systems, cannot be vaccinated. That means parents who choose not to vaccinate their kids, or delay vaccines until their children are older, may be putting others at risk.
Though measles cases are rare in North America today, they're on the rise. Between January and June, 118 cases were reported in United States, more than twice the normal rate for an entire year. In Québec alone, 562 cases were reported in the first six months of 2011.
Dr. William Raszka, a pediatric infectious disease specialist at Fletcher Allen, says that about 40 percent of measles patients are hospitalized, and about one in a thousand will develop encephalitis, or swelling of the brain lining, which can cause brain damage.
"Measles is a terrible disease," he says. "Worldwide, it's still a leading disease killer of children."
So, why do some parents opt out of vaccines? Some likely steer clear of needles out of ignorance, or for religious reasons. However, Patsy Kelso, the state epidemiologist for infectious disease at the Vermont Department of Health, says such explanations account for only a small fraction of the parents who say no.
"People who are opposed to vaccinations for their kids tend to be well read on what vaccines do and how they work," she explains. "The primary objections seem to be, 'Why so many vaccines at the same time?'"
This concern, sometimes referred to as "vaccine overload," is based on a common belief that infants' and toddlers' immune systems cannot handle the growing number of vaccines the Centers for Disease Control and Prevention recommends by age 4. Barbara Loe Fisher, cofounder and president of the National Vaccine Information Center, is a leading proponent of this position. The NVIC is a Virginia-based consumer group that advocates for more independent research into vaccine safety.
Fisher, whose own son was permanently injured by an adverse reaction to the diphtheria-pertussis-tetanus (DPT) vaccine, emphasizes that her organization doesn't advocate for or against specific vaccines, but favors "an informed-consent position."
"We want everyone to have information about the risks and complications about these diseases and vaccines, so they can ask their doctors good questions," she says. "The only thing we're against is forced vaccination."
When Fisher first got involved in this issue in 1982, the CDC recommended 23 doses of seven vaccines before the age of 6. Today, she notes, it recommends 69 doses of 16 vaccines before age 18.
Fisher points to a tripling in the number of children who suffer from chronic conditions such as autism, asthma and diabetes. While she doesn't specifically blame vaccines for those trends, "You can't leave increasing doses of vaccines off the table" when looking for possible explanations, she says.
"Why does the vaccine-safety story not go away?" she asks. "It's because of a lot of personal experience by people who have suffered similar patterns of adverse events following vaccinations."
But Dr. Raszka, who routinely travels the country talking to pediatricians about this issue, says concerns about vaccine overload are unwarranted. He acknowledges that parents who grew up in the 1960s and '70s probably remember getting fewer shots than kids do today. But as he explains, modern vaccines don't contain nearly as many antigens — the substances that stimulate the body's immune response — as vaccines did 40 years ago.
"Everyone hates to see a child poked four or five times," he says. But as for all those vaccines overwhelming the little one's immune system, "It just doesn't happen."
Kelso agrees. In fact, she says, because medical science doesn't show any benefit whatsoever in delaying vaccines until a child is older, putting them off only gives your kid more time to contract the disease — and spread it to others.
Currently, the state of Vermont requires eight vaccines, and recommends four more, in order to register a child for public school or licensed daycare. However, "requires" is a misnomer. Nearly all states permit medical and religious exemptions for vaccinations. Vermont is also one of about two dozen states that allow parents to sign a waiver based on a philosophical opposition. Raszka reports that 5 percent of kindergartners are now covered by waivers.
"It's a balance between individual rights and the state's duty to protect," Raszka says. "There's no easy answer, to be frank. We do know that states that allow for philosophical exemptions have higher rates of pertussis (whooping cough) and higher rates of other vaccine-preventable diseases."
Perhaps the most common fear parents have about vaccines is the risk of complications. None is more widespread than the now-discredited link between the MMR vaccine and autism. This issue first arose in 1998 after an article about it appeared in the Lancet, a well-respected British medical journal. That one article has been blamed for a steep decline in MMR vaccines rates, and corresponding spikes in measles cases, in the United States and Britain, over the last 10 years.
Since it was published, however, the article has been retracted and discredited as fraudulent. Its lead author, Andrew Wakefield, manipulated the research data and was charged with other ethical breaches; he has subsequently lost his medical license.
Still, despite broad consensus in the international medical community that the MMR vaccine is safe, fears persist about a link between autism and vaccines. The reason, Raszka explains, is understandable: Children are often diagnosed with autism spectrum disorder shortly after age 2, which roughly coincides with the timing of the MMR shots.
Today, a small percentage of parents in their thirties and forties are choosing not to vaccinate their kids against less-deadly diseases, such as chicken pox. Many remember a time when nearly all their childhood friends contracted it. Some even attended "pox parties," where kids were deliberately exposed to the disease, which is safer in childhood than in teen or adult years. For most, the experience was no worse than a week of missed school, an itchy rash and perhaps a few small scars.
However, as Raszka points out, even this disease, which many assume is benign, has a darker side. Chicken pox can cause dangerous secondary complications, such as pneumonia, shingles and, if contracted by pregnant mothers, life-threatening birth defects. Prior to 1995, when the chicken-pox vaccine became available, the disease sent about 11,000 people to the hospital every year and killed 100 to 150, according to the CDC.
The good news, says Kelso, is that Vermont has had real success with vaccine-preventable diseases that were common as recently as a decade ago. Pertussis, which can be deadly to infants and newborns, hardly ever appears in the state anymore.
But in order for vaccines to be effective, Kelso warns, they need to work at both the individual and group level. In short, the actions of even one parent can affect — and infect — an entire community. This year in Indiana, for example, 10 kids with measles had contact with 700 other kids. Each had to be contacted to determine if he or she was immune.
"As a parent," Kelso says, "I would want other parents to be vaccinating their kids to help protect mine."