Interferon is effective against these viruses. More specifically, IgA antibodies in the intestine and saliva are protective. Susceptibility to the Rhinoviruses is dependent on prior exposure. Antibody of the IgA and IgG classes is important. Non-specific defenses including interferon, gastric acidity and temperature may play a major role in controlling infection.
Most illnesses occur in the summer and fall.
The virus may be carried in the throat for a week and shed in the feces for several weeks. Inapparent infections occur in about half. On average, most persons suffer with 2-4 colds per year during the fall and spring months and these represent different serotypes of the virus. Diagnosis of enteroviral infections is usually not possible based on clinical presentation. Diagnosis of rhinoviral infections, in contrast, is usually based on clinical presentation.