When I was a boy, in the early 1940s, there were no antibiotics and few vaccines. Kids had all the childhood illnesses--measles, mumps, chicken pox--and bad colds or sore throats that could turn into bacterial infections were cause for concern. An outbreak of polio struck terror into parents' hearts.
It is interesting that while living in Paris, my parents resisted any French influence and continued their Russian way of life: eating Russian food, reading Russian newspapers and books, having Russian friends, and speaking Russian at home. My first tongue was Russian. In the U.S., they did the same thing --continued the Russian traditions they had grown up with.