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So What Exactly is a Rapid Strep Test?

By June 24, 2019September 15th, 2021No Comments

If you have ever visited a doctor for a sore throat, more than likely, you’ve taken a rapid strep test. Simply put, a rapid strep test consists of a medical professional swabbing a patient’s throat with a long cotton swab, obtaining a sample, and, approximately 5 minutes later, giving the patient the results. Behind the scenes, they bring the sample into another room or a lab and put it in a small plastic tube filled with a few drops of acetic acid and sodium nitrite. In 5 minutes, a test strip will show either one line (negative) or two lines (positive).

How does the test work?

Most rapid strep tests use lateral flow technology. The sample on the cotton-tipped swab is applied to a strip of nitrocellulose film and, if Group A strep antigens are present, these will migrate along the film to form a visible line of antigen bound to labeled antibodies. The tests have an accuracy rate of about 95%-99%. Click here to learn more about the reliability of strep tests.

What are the consequences of incorrect results of the Rapid Strep Test?

In the rare case of a false positive, the most likely result is that you will be put on antibiotics unnecessarily. Unless you have an allergic reaction to the antibiotic, this is unlikely to cause you any harm. On the other hand, if you have a false negative test, there would likely be negative consequences if left untreated. After about 9 days of untreated strep throat, the risk of rheumatic fever begins to climb, and irreversible heart damage may occur. Kidney damage may also result if strep throat is left untreated.

You might be wondering what can be done to improve these numbers.  The most important thing is to make sure to obtain a good sample on the swab.  Additionally, it is always wise to get a physician consultation before accepting the results of a self-test. With a professional opinion, the chance of leaving strep throat undiagnosed or misdiagnosed drops considerably. Finally, look out for telltale symptoms of strep throat that will help you and your doctor to keep track of. Click here to learn about the visible symptoms of strep throat.

myphysician360 is the first provider to deliver rapid strep telemedicine consultations with the experience of board-certified physicians.

Written By: Dr. Rob Lapporte

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