When I first told my mother that my partner and I would be taking our daughter to a friend’s wedding in India, my mom cried. “But she’ll have to get vaccinated,” she eventually said, through heavy tears. Because my daughter, who was then 4 years old, still hadn’t been vaccinated. And not vaccinating her is a decision I now regret.

Having a child, especially as an upper-middle-class white lesbian couple, felt like it came with a million decisions. Do we use sperm from a friend or a sperm bank? Do we have the baby at home or in the hospital? Co-sleeper or crib? Björn or Ergo? Cloth or disposable? On and on and on.

So to be honest, when my mom—a mathematician with a fast Internet connection who I love deeply and trust implicitly—sent us a 46-page report on the pros but mostly cons of vaccines, it just seemed like one less decision to make. “In most cases the risk of harm to a healthy, breast-fed infant from a vaccination far exceeds the risk of harm from the disease itself,” my mom wrote on page 1.

The following pages seemed very convincing. The statistics made it look like it was far more likely for our daughter to be hurt by the side effects of the vaccines than to catch the various diseases against which the vaccines protected. We didn’t consult any other sources. We were overwhelmed, and perhaps slightly lazy, new parents.

We were also singularly, obsessively concerned with the health and safety of our baby girl. Suddenly my partner and I were solely in charge of an entire human being, one who seemed somehow more fragile than other babies we’d known, because this one was relying on no one but us for her sustenance and survival.

I remember a nurse at the hospital looking at me as we were preparing to go home, me cradling our daughter in my arms, with a look on my face like a deer caught in the headlights of the realization that the hospital staff wouldn’t be coming home with us. “Don’t worry, hon,” the nurse said, putting her hand on my shoulder. “You’re now the world’s foremost expert on your baby. You know more about what she needs and wants than anyone else in the world.”

This was comforting. And terrifying. I didn’t feel like I knew very much.

Those first few weeks, even months, of parenthood feel like a blur—partly out of sheer exhaustion, but also the effort of trying to be ever-present bubble wrap, protecting my daughter from any danger imaginable—especially my own novice parenting.

It didn’t help that I’m Jewish. We’re a neurotic and paranoid tribe. Nor did it help that we were upper-middle-class white women living in a fancy neighborhood that seemed a million miles away from diphtheria or hepatitis B. Hepatitis B is mainly passed through sex, for crying out loud. The prospect of sex was a long way off for my daughter. Heck, at the time, it seemed a long way off for her parents, too.

But fundamentally, I’m embarrassed to say that the idea that we might be putting other people at risk by not vaccinating our daughter never really crossed our minds. We were focused on keeping our daughter safe, and little else.

That was a mistake.

“Our fears are dear to us,” writes Eula Biss in her powerful and important book, On Immunity. Biss notes that a lot of the parents who are skeptical of vaccinations, like we were, are the same people who worry about hormones in meat and pesticides on vegetables. We’ve been told by our industry-cozy government that these things aren’t toxic, but we suspect that’s not right. We seek out farm-to-table food and even organic baby wipes as a prudent expression of that caution and care.

Why trust the government and pharmaceutical industry when it comes to vaccines? That skepticism doesn’t seem selfish, but smart. Until it isn’t.

Biss reminds us that the point of vaccines isn’t just to protect ourselves but our entire community. As a progressive, you’d think I’d get this. It’s why I pay taxes willingly, even gleefully. That’s why I don’t mind that most of my federal taxes go to benefit not my own home state of New York, which is a net contributor of tax revenue, but states like South Carolina and North Dakota, which are net takers of federal tax dollars. I’m more than happy to do my part to help my fellow human beings. And yet… Biss writes, “a privileged 1 percent are sheltered from risk while they draw resources from the other 99 percent.”

She’s not talking about taxes. She’s talking about infections. In the past, it was thought that low vaccination rates were due to low-income families lacking access to doctors and medical care. Now, low vaccination rates appear more often linked to well-off families opting out.

In the case of Obamacare, I have no problem morally or politically being required to pay for private health insurance to help lower the cost for those who can’t afford the full price of insurance on their own. I’m happy to do so for the sake of public health and the greater good. How is vaccinating my child any different? How did I manage, for so long, to think it was somehow different?

If parents like me keep opting out of vaccines, the likely outbreaks will end up hurting everyone, and especially those without adequate medical coverage. The people, in other words, I support Obamacare to help.

Evolutionary biologists say selfishness is a natural instinct, but so is the desire to become close to others. And the more some people selfishly choose not to vaccinate their children, the more the risk of infecting others increases.

The current measles outbreak in the United States appears to have started at Disneyland in California. And because it’s a small world after all, there are over 100 confirmed cases of measles in 14 states and Mexico. The latest case is a student in the New York area. Thankfully, it’s not my daughter.

Thanks to our change of heart a few years ago, and our trip to India, my daughter is now fully vaccinated. She attends a wonderful, diverse public school in New York City where she can learn all the good lessons about community and connectivity. And the only thing infectious about her is her laughter.

If we had to do it all over again, we definitely would not have waited so long to vaccinate our daughter. Being vaccinated is a civic and community responsibility. And it’s one we should all take much more seriously.