Back in the early 1950s, both my younger sisters, the youngest, only a few months old caught whooping cough, the baby was very severely ill and I can remember hearing the doctor say to my mother, 'one more coughing fit like that and she will need to go to hospital'. The elder had it exceptionally badly and it was three months before she was well enough to return to school.
I was spared because when the doctor came to see my sisters, I had yet to get it. The whooping cough vaccine had come into use but was not yet universal, but the doctor returned a few hours later to vaccinate me against the disease so I did not get it.
My closest friend had whooping cough, which damaged her lungs and ever since she has lived in fear of getting respiratory infections and I have lost count of the number of times she had had to be hospitalised, some times for weeks at a time when she has had them.