In the 1960s, a public health scare erupted over a rather mild virus. The symptoms it caused in adults were similar to those of a common cold, but it could cause deafness, heart defects, mental disabilities, or even death in babies born to mothers who were infected during pregnancy.

This wasn’t Zika—it was rubella. And in the U.S., it had a profound effect on society. Abortion had been a taboo subject until then, but people began to advocate for abortion as a medical, not a moral, decision. Recent statements by public officials in Brazil and Colombia hint that Zika might have a similar effect in countries where abortions still are, with few exceptions, illegal.

The first reports that rubella, also