Subclinical infection

In medicine, a subclinical infection refers to an inapparent, asymptomatic infection, or an infection that has such a mild course that it doesn't alert the patient enough to consult with a physician.

An example could be a mild case of the common cold; the patient feels a little sick, but this feeling is so common that he or she doesn't address a general practitioner.

Because many infections do not come to clinical attention, health statistics sometimes don't represent the true prevalence of the condition in the population.

Another problem with subclinical infections is that the infectious agent is able to dwell in the patient's body long enough to infect another person. The time between infection and symptoms is called the incubation period; during this time, the patient has a subclinical infection, and can (unwillingly) spread the infectious disease to others. This is the case, for example, for subclinical sexually transmitted diseases such as AIDS and genital warts in women.

Another common subclinical infection is a urinary tract infection, particularly in women. If a pregnant woman doesn't get proper treatment, this may cause preterm delivery.