We all benefit from vaccinated areas

Dear Dr. Roach: I read your column on vaccinations and was bothered about one issue that has not been addressed. Who are “antivaxxers” putting at risk by not having their kids vaccinated? Those who are vaccinated are not at risk, right?

I generally support people’s right to deny entering programs they disagree with, even if they are ignorant conclusions. — T.R.

You would be correct if vaccines were 100% effective and if everyone could get them, but neither of those are true.

Two doses of measles vaccine are about 99% effective, but that still means that with widespread measles transmission, one person in a hundred could still get measles even if vaccinated. The reason that hasn’t happened in the past few decades is that there has been enough vaccine coverage that there has not been widespread transmission. This is called herd immunity, and is the major reason that people seldom die from measles now.

The success of vaccines has led to a situation where people no longer know how serious measles can be. Once vaccine coverage drops below 95% or so, then sporadic cases and even ongoing transmission are possible.

Unfortunately, some children and adults are unable to be vaccinated due to underlying immune deficiency, illness or chemotherapy. These people are at extreme risk of death from measles, and the ONLY way to protect them is through herd immunity. I believe there is a moral obligation to get vaccinated for a person who lives in society to protect others.

Since people are infectious with measles before it can be diagnosed, a person’s right not to get immunized is outweighed by the cost to others who could be exposed. This is why public health officials are able to quarantine people who are not vaccinated and infectious, and on occasion, to forcibly vaccinate them.