We catch colds and cheerfully sneeze and cough over each other. I've never seen anyone walking around Cambridge wearing a mask. Mind you, when I get a cold I look so awful that I might take up wearing a mask - not to prevent the spread of infection but to spare people the sight of my red eyes and runny nose. A large brown paper bag work even better!

We catch colds in the US, but it is very uncommon to wear a mask to prevent spreading colds. You'll sometimes see people who have allergies wearing a mask when they mow the lawn or do yard work.

I pray that everyone remains healthy. Asia suffered a bad SARS epidemic in 2002-3, during which the World Health Organisation urged everyone to wear a mask. Since then, there has been a higher awareness of the importance of simple daily measures of prevention of viral diseases. It is a wonderful thing to have a sense of humour, but I think the Japanese practice of wearing a medical mask is not to be lightly derided but should be admired and encouraged.

Only the WEAK ones.

Before we understood the carcinogenic nature of excessive sun bathing and smoking, non-sun-bathers and non-smokers were considered unfashionable and teased. It is human nature. We know better now. Those who have had family members taken away by smoking-induced lung cancer no doubt understand it even more.