What pathogen causes the common cold?
FYI: viruses are not able to reproduce on their own. They must have a host cell in order to reproduce. This is because a virus is a strand of RNA or DNA- usually RNA. In a nutshell, the virus invades a human host cell- usually in the mucous membranes of the nose or throat. The virus then locates the small organelles of the cell that produce protein chains, and inserts itself in such a way as to become the RNA template for those chains. In other words, the cell is producing viruses instead of the normal protein chains. The cell eventually ‘fills up’ with virus particles, and then lyses, or ruptures, spilling virus particles out to infect other cells. (This rupturing is an immune response of the cell). This causes the host immune system to kick in, producing the symptoms of a cold. This process takes several days, known as the incubation period. Colds are contagious approximately 24 hrs before any symptoms start.
