Medical Examiner

My Son, the Statistic

If I had to do it over, I would vaccinate him again.

baby and vaccines.
A single dose of MMR induces immunity in 93 percent of children. 

Photo illustration by Slate. Photo by Katarzyna Bialasiewicz/Thinkstock.

Like every parent, I worry. From the day my baby boy entered the world, I worried whether he slept enough, whether he ate enough, whether he ate too much. I worried about the typical—shouldn’t he be walking already?—and the ridiculous—should I be researching kindergartens? (I worry about his privacy, too, so I will call him Oscar in this story.) But I worried most about the inevitable times when I wouldn’t be able to protect him—and worse, when a decision I made would cause him pain.

That day came about a week after his first birthday, when most—though unfortunately not all—American children get a suite of vaccines, including the MMR combo that fends off measles, mumps, and rubella.

I should say up front that I am not an anti-vaxxer. When I quizzed the doctor about possible side effects of vaccination at my son’s one-year checkup, I did so more out of my science-journalist habit than any concern that her answers might change my mind. She ran through the most likely: mild symptoms such as fever or rash. And when pressed for the less likely, she listed seizures caused by fever or a severe allergic reaction. Appreciating her candor and satisfied that Oscar would beat the odds, we went ahead with the shots.

A week later, odd things began to happen to Oscar. It started with a bloody nose during lunch. He had never had a bloody nose, but it wasn’t severe, so I didn’t think much of it at the time. In the following days, I noticed blood around his gums and strange, small bruises on his legs and bottom. Their pattern caught my attention—rows of circular bruises arranged as if he had been repeatedly jabbed with three fingers. I couldn’t imagine a fall or injury that could have caused them. I found clusters of wine-colored spots the size of pinpricks on his shoulders, his back, and his legs. These dots, which I would later learn were called petechiae, are caused by bleeding under the skin and should have been a telltale sign that something was wrong. Instead, the first doctor we saw, in the emergency room, diagnosed Oscar with a rash and told me to see a pediatrician if he developed other symptoms.  

When the bruises and spots kept appearing, I started to doubt his diagnosis, so I made an appointment with Oscar’s pediatrician. She ruled out leukemia—a possibility that thankfully hadn’t occurred to me. But a blood test revealed that his platelet count was low—20,000 per microliter, compared with a normal count in the range of 150,000 to 450,000.

It turns out that one side effect of the MMR vaccine that she didn’t mention—because it is so rare—is immune thrombocytopenia purpura. In a person with ITP, the body attacks its own platelets, the cells that help blood to clot. This immune-system insurgence leaves the body without enough platelets to stop bleeding when injured. ITP is treatable (and mild cases can resolve without treatment), but it’s also potentially life-threatening, particularly because head trauma in someone with ITP can cause bleeding in the brain—a frightening prospect when the patient is a 1-year-old whose head bears the brunt of his burgeoning walking skills.

Though it’s more common in children who have had viral infections like chickenpox, ITP occurs after 1 in 40,000 MMR vaccinations, according to the Centers for Disease Control and Prevention. Oscar was that one.

When the doctor came back into the room, she said what no parent ever wants to hear: Oscar needed to be hospitalized immediately. I was crying before she finished her sentence.

The treatment, a 12-hour intravenous infusion of antibodies, would require an overnight stay—and would also require four adults, myself included, to restrain my (surprisingly strong) baby as the IV needle was inserted into his foot. This was easily my worst day. My rational mind battled a surging fear as I sat in Oscar’s dark hospital room as the machines dripped immunoglobulins into his veins. What if my attention lapsed for a moment and he smacked his head on the hospital crib? Could he already be internally bleeding from a bump earlier in the day? What if the treatment doesn’t work? Will we have to pad our whole house and never let him play outside? Will he get to have a normal childhood?

My only consolation during that long night in the hospital was the fact that he wasn’t actually feeling sick. Once the needle was in his foot, he was his usual jolly self. I’ll never forget the sound of his laughter as he played peekaboo in the hospital crib. As it echoed down the peds ward full of children truly suffering from their ailments, I heard a nurse say, “I wish I could bottle that laugh.”

The next morning, the doctors arrived with the blood test results: The treatment had successfully repopulated his platelets—his count was up to 250,000. He was safe.

Except that two months later, my home state of California became the epicenter of a measles outbreak. It was the second-largest measles outbreak since 2000, when the disease was declared eliminated from the United States. (The largest—383 cases—was brought to a largely unvaccinated Ohio Amish community in early 2014 by missionaries to the Philippines.) The California outbreak, likely originating with an international traveler to Disneyland, led to 147 cases throughout the United States, 90 percent of those in California.

The CDC recommends that all children receive two doses of the MMR vaccine. A single dose induces immunity in 93 percent of children. The second dose—typically given between the ages 4 and 6 before kids start school—will catch an additional 4 percent. However, this second shot can be given earlier—as soon as one month after the first dose. With an outbreak looming on our doorstep, we suddenly had to face the question: Should we give Oscar his second MMR vaccine now?

The memories of our hospital stay were still fresh, and that visceral fear doesn’t sit by quietly in the face of rational risk analysis. But listening to that voice of dread, I had to weigh my fear of ITP against a lifetime of worrying that he could contract measles anytime we went on vacation, to the park, or to the grocery store. Vaccines come with risks—rare but real risks. I knew this better than almost anyone. But it’s easy to focus on those unlikely risks now that parents no longer have firsthand experience with the even more devastating risks of the diseases these vaccines have vanquished. The measles vaccine has reduced the number of measles cases by 99 percent. Before the vaccine, 3 million to 4 million people in the United States contracted the disease every year. A quarter of those were hospitalized; about 4,000 developed encephalitis, or brain swelling; and 400 to 500 people died each year. Measles is so contagious, according to the CDC, that an infected person will spread the disease to 90 percent of unvaccinated people in close contact.  

Despite everything that had happened, I knew I would vaccinate Oscar again. If I could do things over, I would have argued more with the ER doctor who dismissed his petechiae as a rash; I probably would have made Oscar wear a helmet. But I wouldn’t have thought twice about vaccinating him. More than 730,000 American lives have been saved in the last 20 years thanks to our childhood vaccine program. In spite of a doctor who misdiagnosed, in spite of my son being an unlucky statistic, I still believe that the collective knowledge of the scientific and medical community—based on decades of vaccine research—is our best bet for saving lives and eliminating diseases.

While I was tormenting myself with worry, the doctors and nurses who treated Oscar acted like it was just another day. Because of course, for them, my son’s scary, potentially life-threatening crisis was just another day. I felt a renewed awe for a medical system that was staffed with professionals who had dedicated their lives to learning and then improving how we treat and prevent diseases. Their even-keeled confidence in their abilities to heal reconfirmed to me that they are the experts.

Many people are shocked and frustrated that we’re having a debate about vaccines at all, but on some level, I get it: Parents worry about making the wrong choices for their children. The question comes down to whom to trust. The anti-vaccine movement spreads a misguided belief that expertise is overrated—that a hunch or a personal experience or a friend’s post on Facebook is more reliable than hundreds of thousands of specialists evaluating mountains of data, that a half-hour of Googling confers more competence than years of medical training.

My faith in these experts is not blind. I know that doctors and researchers make mistakes. And, worse, some of them have on occasion abused our trust. They aren’t perfect, and neither are vaccines. But together they are saving countless lives every day, in the safest way humanity knows.

In the end, Oscar didn’t need a second dose of MMR. His doctor recommended that we check first to see whether he got immunity from the first shot. I almost cried again when she called back with the results. “He’s immune,” she said.

Last week we were back in the doctor’s office for Oscar’s 18-month checkup and another set of vaccines. As the nurse came in, I gave Oscar a big hug and told him it would be over soon. Then I went back to worrying about what he would have for lunch.

Read more of Slate’s coverage of vaccines.