I know it was a long time ago, and things have changed very much since then.
My mother had her first child a boy Gary in 1952, she bottle fed, and was paranoid about germs everything had to be boiled before it touched him, he wasnt allowed to crawl on the floor and she would only put him down on a blanket that was always being washed.
When he was 9 months old. my Parents were posted to Singapore (my DF was RAF)
It was a long flight and a stop over in Pakistan, Mum had taken bottled boiled water with her but ran out in Pakistan, she asked for fresh boiled water in the hotel and fed the baby.
By the time the flight took off again, the baby was being sick, by the time they reached Singapore he had diarrhoea.
He was taken into hospital the next day, the Doctors told her it was gastroenteritis. They thought that maybe the water hadnt been boiled enough, and because Mum was so fanatical about hygiene, he didnt have the
immunities to fight it.
My brother died the next day.
Mum went onto have five more children, including twins, we were mucky sods,
allowed to be dirty, (mum called it clean dirt, washed off in the bah at night)
When I had DS 35 years ago, she went made seeing me Milton everywhere, insistent that washing the surfaces down with a clean cloth and hot water was more than enough.
I took her advise, DS was another mucky kid who was batherd each night.
It was enough.