Holding your breath may help you to avoid a cold, but a far more effective method for staying virus-free is to wash your hands regularly and encourage any sick people around you to do the same. When someone has a cold, the cold virus multiplies inside their nose and throat secretions. Each cough or sneeze then expels tiny droplets containing the virus. Breathing in these droplets can lead to infection, but the most common way of catching a cold is actually by touch. After sneezing into their hands, the sufferer touches other people, objects or surfaces such as towels or door handles. This can in turn contaminate other people’s hands, enabling the virus to enter their bodies when they touch their face or when they eat.
Answered by Alex Cheung