There are more than 100 different viruses which can cause common cold. But the most commonly involved virus is rhinovirus, which cause up to half (50%) of all common cold infections. Other commonly involved viruses include corona viruses (which is a type of picorna virus and causing 10-15% of common cold infections), influenza viruses (causing 5-10% common cold infections), para-influenza viruses, human respiratory syncytial viruses, adenoviruses, enteroviruses etc. Among adults majority of common cold infections are due to corona viruses with 99 known serotypes and probably larger numbers of unknown serotypes.

All humans (non healthy as well as healthy persons) are susceptible to common cold infections, and preschool children are particularly more prone to get infected by common cold viruses. Immunity against one type of virus does not help in preventing infection by another type of common cold causing virus and a person may have common cold several times a year.

Common cold is common in particular season or time of the year. Common cold is more common during time of fall and winter season due to several reasons. During winter people tend to remain closer to each other in compare to summer or other seasons, which makes it easier to transmit the virus from one person to another. In the tropical regions where winter season is mild or absent, common cold is more frequently seen during rainy season, may be due to getting wet in rain more frequently.

Children are more prone to common cold in compare to adults and aged persons, as children have not developed immunity against most common viruses responsible for cold. As children grow older the frequency of attacks of common cold reduce. Children also tend to have frequent cold de to close mixing with peer age group.

Related posts: