Lifesaving, safe vaccines
WHILE THERE are many debatable issues in the autism world, vaccines are no longer among them. This is a blessing for parents, children, and pediatricians. The real tragedy of the suggestion that vaccines cause autism is that millions of research dollars have been diverted to disprove a relationship that never existed to begin with
A number of large studies, in the United States, the United Kingdom, and Scandinavia, have failed to find a link between vaccines and autism. But this is an issue that doesn’t want to die, so pediatricians like me end up spending time reassuring parents that we truly have their children’s best interests at heart when we immunize them, that we are not in the pockets of the pharmaceutical industry, and we read the literature with a healthy dose of skepticism.
In 1998, the original paper that suggested a link between autism and vaccines, specifically the measles-mumps-rubella vaccine, was published in the prestigious medical journal Lancet. There were almost immediate concerns about the validity of the study’s science. However, rates of MMR immunizations plummeted in the UK, especially in London, where rates were as low as 50 percent in some areas. Outbreaks of measles occurred in London, Scotland, and Ireland, and the United States. Hundred of children fell ill, and in one Dublin hospital, 100 children were admitted with pneumonia and swelling of the brain, and three died. We don’t know the long-term effects of the illness in the other 97, but measles is associated with deafness and long term neurological effects.
Investigations into that original case series revealed shocking ethical violations, including no committee approval at the beginning, the recruitment of children through personal injury lawyers rather than randomly, and the fact that only eight children with autism were examined, a startlingly small number. But the theory was off and running and frightened parents of infants and small children started questioning the safety of vaccines, and not just the MMR vaccine, but all vaccines.
Not one study was able to replicate the findings in the original Lancet paper. Twelve large epidemiological studies have failed to find any such link. Last month, the original 1998 paper was “retract(ed) from the published record’’ by Lancet, an exceedingly rare occurrence.
What makes this an issue that won’t go away? One reason is our wish to explain reports of the increasing prevalence of autism. While current estimates are that 1 in 100 American children has a diagnosis on the autism spectrum, with nearly four times as many boys as girls, the term “spectrum’’ warrants some explanation. A good number of children “on the spectrum’’ are children with normal intelligence but some developmental quirks. In many cases, these are kids who would not have had any diagnosis at all 30 years ago.
Another worry for parents is the timing of their concerns in relation to the administration of vaccines. About 25 percent of children diagnosed with autism have a reported history of developmental regression or arrest between the ages of one and two. For most parents the first thing they notice is their child has delayed language. Because vaccines are given at 12, 15, and sometimes 18 months, there is a temporal relationship between parents becoming concerned and the administration of vaccines. But in fact, expert eyes can see the signs of autism before parents may. Recently, researchers have followed infant siblings of children already diagnosed with autism from six months of age to look for the earliest signs of autism. Those studies have shown that at 12 months of age, the children later to be diagnosed with autism already look different. Vaccines given in the second year of life cannot explain these differences. So, while a real regression occurs in some cases, especially those for whom a genetic syndrome is the cause of the disorder, many behaviors are so subtle in a one-year-old as to be missed by parents. It isn’t until a child is not doing something expected, like talking, or pointing, or following a point, or turning his head when you call his name, that we become concerned.
In my training in the 1980s, I cared for a great number of babies and children with illnesses now prevented by vaccine. One of the sickest had HIB meningitis and left the hospital brain-damaged. I saw cases of devastating measles in children born outside the United States and not immunized. As recently as the mid-1990s, there was an outbreak in a child-care center in Jamaica Plain of “flesh-eating strep’’ among children who contracted chicken pox and strep infections at the same time. Ask any grandmother about the time her children had measles, or rubella, or polio.
So where does that leave us? The supposed link between vaccination and autism has been put to rest. We do know there is a genetic component to autism. Twin studies, including one at the Kennedy-Krieger Institute in Baltimore, reveal a 90 percent concordance among identical twins and a 6-8 percent concordance among fraternal twins and non-twin siblings, still significantly higher than the 1 percent prevalence rates reported in the general population. Recent studies have suggested that older parents are more likely to have children with autism. Older parents are more likely to have conceived through assisted reproduction and researchers are evaluating a possible impact there. Autism experts are encouraging families to enroll their children in genetic studies, and Boston has some of the best autism clinicians and researchers in the world. With more data from today’s children with autism, we are more likely to find the answers we seek.
Eileen Costello is a pediatrician in Jamaica Plain and recently completed an autism fellowship at Boston Medical Center.