It might, however, protect against infection by a related, worse virus. As well as it often being safer to be infected earlier in life than later on (which requ

It might, however, protect against infection by a related, worse virus. As well as it often being safer to be infected earlier in life than later on (which requires a fair amount of spread along children). There is a related hygiene hypothesis for polio, but luckily we don't have to deal with that anymore. On the whole, eradicating the flu and colds would probably (in my opinion) be a net positive, but you have to be a bit careful with these things.