A throat swab is a type of outpatient medical diagnostic test in which a cotton swab is swiped across the inner surface of the throat near the tonsils in order to obtain a small tissue sample. This test is most often used to diagnose whether or not a patient is infected with a bacterial infection of the throat — typically streptococcus infection, more commonly known as strep throat. The throat swab test is also called a throat culture or strep culture.
Strep throat is a fairly common illness, often spread in the winter months. It is easily passed from person to person via coughing, sneezing, and sharing food or drinks. The most common symptom of strep throat is a sore or itchy throat. Other symptoms may include painful swallowing, bad breath, earache, headache, stomach ache, mild fever, swollen and sore tonsils and neck glands, red, white, or yellow spots in the throat or on the roof of the mouth, and runny nose. The presence of these symptoms may prompt a health care provider to do a throat swab in order to determine the best course of treatment.
In order to perform the test, the patient is asked to tilt his or her head back with the mouth wide open. A long cotton swab is then rubbed on the back of the throat a few times to obtain a sample. This often causes the patient to experience a gagging reflex, and in some rare instances this gagging reflex may cause the patient to cough or vomit. The test is generally well tolerated and poses minimal risk to the patient.
Throat swab tests can be administered in a doctor's office or at a medical clinic, and some pharmacies offer a type of throat swab known as a rapid strep test for a quick diagnosis. The rapid strep test produces results within minutes, where a more thorough throat culture will yield results in one or two days. If infection is found to be present in the throat, the patient will often be administered a ten-day round of antibiotics to eliminate the bacteria and help prevent the spread of infection to others. With medical treatment, the patient ceases to be contagious within 24 hours of starting antibiotics, and pain will last one to three days. The patient must take the full round of antibiotics in order to completely clear the infection and prevent re-infection.