Strep Throat Rapid Test at Urgent Care: What to Expect

How does a rapid strep test work at urgent care?

A clinician swabs the back of your throat (tonsils and pharynx) with a sterile swab. The swab is placed in a reagent that detects Group A Streptococcus antigens. Results come back in five to ten minutes.

If the rapid test is positive and your symptoms match, antibiotics can be prescribed at the same visit. If the rapid test is negative but your symptoms strongly suggest strep, many clinicians send a throat culture to a lab — which takes 24–48 hours — because rapid tests can occasionally miss a true infection. The IDSA recommends that in children and adolescents, a negative rapid test should be followed by a throat culture, since the rapid test is specific but not perfectly sensitive 1Ref 1Shulman ST, Bisno AL, Clegg HW, Gerber MA, Kaplan EL, Lee G, Martin JM, Van Beneden C (2012).Clinical practice guideline for the diagnosis and management of group A streptococcal pharyngitis: 2012 update by the Infectious Diseases Society of America.Recommends rapid antigen testing before antibiotic prescribing; penicillin/amoxicillin as first-line agents; back-up throat culture for negative rapid tests in children; contagion and return-to-school guidance.

How do clinicians decide whether to test for strep at all?

Not every sore throat is strep. Most sore throats are caused by viruses, and antibiotics do not help viral infections. Clinicians often use a validated scoring system — the modified Centor (McIsaac) criteria — that weighs four findings: fever, no cough, swollen tender lymph nodes in the neck, and tonsillar exudates (white patches on the tonsils), with an age adjustment 2Ref 2McIsaac WJ, White D, Tannenbaum D, Low DE (1998).A clinical score to reduce unnecessary antibiotic use in patients with sore throat.Validation of the modified Centor (McIsaac) scoring system — fever, no cough, swollen lymph nodes, tonsillar exudates, age — for predicting Group A Streptococcus and guiding testing decisions. A higher score makes strep more likely and testing more useful.

If your sore throat comes with a runny nose, cough, and hoarseness, a viral cause is more likely and a strep test may not be needed 1Ref 1Shulman ST, Bisno AL, Clegg HW, Gerber MA, Kaplan EL, Lee G, Martin JM, Van Beneden C (2012).Clinical practice guideline for the diagnosis and management of group A streptococcal pharyngitis: 2012 update by the Infectious Diseases Society of America.Recommends rapid antigen testing before antibiotic prescribing; penicillin/amoxicillin as first-line agents; back-up throat culture for negative rapid tests in children; contagion and return-to-school guidance.

What antibiotics are used if strep is confirmed?

Penicillin and amoxicillin remain the preferred treatments for Group A strep pharyngitis because strep has not developed resistance to them 1Ref 1Shulman ST, Bisno AL, Clegg HW, Gerber MA, Kaplan EL, Lee G, Martin JM, Van Beneden C (2012).Clinical practice guideline for the diagnosis and management of group A streptococcal pharyngitis: 2012 update by the Infectious Diseases Society of America.Recommends rapid antigen testing before antibiotic prescribing; penicillin/amoxicillin as first-line agents; back-up throat culture for negative rapid tests in children; contagion and return-to-school guidance. For people with a penicillin allergy, alternatives such as cephalosporins or clindamycin are available. Antibiotics shorten the duration of symptoms, reduce contagiousness, and — importantly — prevent rare but serious complications like rheumatic fever 3Ref 3van Driel ML, De Sutter AIM, Habraken H, Thorning S, Christiaens T (2013).Different antibiotic treatments for group A streptococcal pharyngitis.Antibiotics reduce symptom duration and suppress Group A Streptococcus to prevent complications including rheumatic fever; supports antibiotic treatment when strep is confirmed.

A clinician will determine the appropriate antibiotic and course length. Gale's primary care team can help with follow-up questions or if symptoms persist after starting treatment.

Can a telehealth visit diagnose strep throat?

A telehealth clinician can assess your symptoms, calculate a Centor/McIsaac score, and order an at-home strep test kit or direct you to a nearby pharmacy that performs rapid tests 2Ref 2McIsaac WJ, White D, Tannenbaum D, Low DE (1998).A clinical score to reduce unnecessary antibiotic use in patients with sore throat.Validation of the modified Centor (McIsaac) scoring system — fever, no cough, swollen lymph nodes, tonsillar exudates, age — for predicting Group A Streptococcus and guiding testing decisions. However, a clinician cannot swab your throat remotely. If you are in significant pain, have difficulty swallowing, or appear systemically ill — high fever, drooling, stiff neck — an in-person visit is essential.

How contagious is strep, and when can I return to work or school?

Strep is highly contagious through respiratory droplets and direct contact. Most clinicians advise staying home until you have been on antibiotics for at least 24 hours and you are fever-free. After that point, the risk of spreading the infection drops substantially 1Ref 1Shulman ST, Bisno AL, Clegg HW, Gerber MA, Kaplan EL, Lee G, Martin JM, Van Beneden C (2012).Clinical practice guideline for the diagnosis and management of group A streptococcal pharyngitis: 2012 update by the Infectious Diseases Society of America.Recommends rapid antigen testing before antibiotic prescribing; penicillin/amoxicillin as first-line agents; back-up throat culture for negative rapid tests in children; contagion and return-to-school guidance.

Wash hands frequently and avoid sharing cups or utensils while symptomatic.