At-home Strep Throat Testing
- Also Known As:
- Rapid At-Home Strep Test
- At-Home Group A Streptococcus Test
- At-Home GAS Test
- Strep Rapid Antigen Detection Test
Test Quick Guide
Strep throat testing looks for an infection with group A streptococcus (GAS) bacteria, which are also known as strep A. These bacteria are best known for causing sore throat, and strep throat infections are most common in children between the ages of 5 and 15.
At-home strep throat tests are designed to analyze a throat swab to see if strep A bacteria are present. These rapid self-tests can be fully conducted at home, but test results should be discussed with a doctor.
About the Test
Purpose of the test
The purpose of strep throat testing is to check for an infection with strep A bacteria. At-home tests for strep throat are able to detect the presence of strep A antigens, which exist on the surface of the bacteria and trigger an immune response.
In general, strep A testing is done to distinguish strep throat from other causes of a sore throat. This is important because antibiotics are effective for strep A infections but are not helpful for viral infections like the common cold.
Testing for strep throat in children and adolescents is also important because an untreated strep A infection can lead to more serious symptoms and complications, such as rheumatic fever. Detecting and treating a strep A infection may also help prevent spreading the infection to other people.
At-home testing may help to serve these same goals, but it is important for the test to be used and interpreted correctly. For this reason, it is best to consult with a doctor about how to interpret your at-home test results and what the next step will be after testing.
What does the test measure?
An at-home strep throat test measures whether there are any specific antigens to strep A in a sample taken from a swab of the tonsils and throat. An antigen is a substance that provokes a reaction from the body’s immune system. The presence of strep A antigens generally reflects an active infection with strep A bacteria.
However, a significant percentage of children carry strep bacteria in their throats even when they are not sick. These individuals are called “strep carriers.” They may also test positive on an at-home strep throat test despite not being sick with strep throat.
When should I get an at-home strep throat test?
Testing for strep throat is tailored to a person’s specific circumstances, and there are no universal guidelines for when to use at-home strep testing. For this reason, it is best to talk with a doctor about whether at-home testing is appropriate in your situation.
Strep A is most common in children and adolescents between the ages of 5 and 15. For this reason, doctors are more likely to test for strep throat in people of these ages if they have symptoms like a sudden sore throat, a fever, enlarged lymph nodes, or a rash. Strep A testing may also be ordered if someone has symptoms along with a known exposure to someone who has a strep A infection.
However, a strep A test is not always done in people with a sore throat. In many cases, sore throat is caused by a viral infection. Viral infections often trigger additional symptoms like a runny nose or coughing. As a result, doctors may reserve strep A testing for situations when sore throat occurs without other symptoms of a viral infection.
Routine strep A testing is not usually used in adults or in children under three years old. In these groups, it is rare for strep throat to cause complications, so it is less important to detect a strep A infection early. However, a doctor is in the best position to assess the appropriateness of strep testing for a specific patient’s case.
While at-home tests make strep A testing convenient, testing is not appropriate in all situations. It is possible to have a viral infection that causes symptoms while also having asymptomatic presence of strep. In these cases, a positive result on strep A testing may lead to unnecessary use of antibiotics because the cause of symptoms is viral rather than due to strep.
Because of the nuances involved in determining whether strep A testing is appropriate, it is best to talk with a doctor before taking any strep A test.
Benefits and Downsides of an At-Home Strep Throat Test
There are pros and cons to every medical test. Understanding the positives and negatives of at-home strep throat testing can help you make an informed decision about whether to purchase an at-home test kit.
Some of the primary potential benefits of at-home strep throat testing include:
- Convenience: Test kits make it easy to conduct the test in the comfort of your own home and on your own schedule without having to make an appointment.
- Early detection of a strep A infection: Identifying a strep A infection earlier can help avoid transmission of strep throat to others and speed up the start of antibiotic treatment that can improve symptoms and prevent complications.
- Reduced doctor visits: Going to the doctor every time that a child has a sore throat or other symptoms can be burdensome. The ability to do a rapid at-home strep throat test may reduce the need for some doctor visits. However, doctors will not always treat a patient solely based on the results of an at-home test and may require confirmation testing in person.
- Affordability: While at-home strep tests are not usually covered by insurance, their relatively low cost per test is often less than copayments or deductibles.
Possible downsides of at-home strep throat testing include:
- Risk of test error: Properly taking the throat swab sample and preparing the test materials is essential to accurate testing. Since most people are untrained in collecting a throat swab, there may be more risk of user error for at-home testing.
- False negative results: A false negative is when a person actually has a strep A infection but the test finds no signs of that infection. This type of misleading result may cause a delay in proper treatment. Unfortunately, false negatives can occur with rapid strep tests and may be more likely if an at-home test is not properly conducted. In a medical office, a negative test is often confirmed with a throat culture test, but this kind of two-tier testing is not offered with at-home kits.
- Lack of test interpretation: At-home tests provide a straightforward positive or negative result, but this can oversimplify the situation in patients with symptoms. In a medical office, the doctor assesses the specific symptoms and whether they are likely to be caused by strep A or another type of infection. This can directly influence how test results are interpreted and whether treatment is needed.
- Follow-up may be required: For patients who test positive, receiving the proper antibiotics requires a doctor’s prescription. In most cases, this is likely to mean having to go to the doctor’s office and taking a repeat strep A test.
Types of At-Home Tests
At-home strep tests are a type of rapid strep test that may also be called a rapid antigen detection test (RADT). Similar RADTs are often used in doctor’s offices.
There are numerous products available for at-home strep throat testing. Most of these products include enough materials to conduct the tests multiple times.
The following sections detail our picks for the top at-home strep throat tests that you can purchase online.
Areta – Strep A Swab Test Kit
Price: $44.56 (25 tests)
Sample: Throat swab
Results timeline: Within 10 minutes
The Areta Strep A Swab Test Kit is our best overall pick for checking for a strep throat infection.
This rapid test kit includes everything you need to conduct a strep A self-test or to test a child. To take the test, mix five drops of two separate reagents in a provided tube. Taking care not to touch the tongue, rub the sterile swab that is included with the kit on the back of the throat. Then take the throat swab and carefully swirl the swab in the tube with the reagents 10 times.
Once you have removed the swab, dip one of the test strips into the tube for exactly five seconds. After ten minutes, the test strip will display the result as positive, negative, or invalid if there was an error in preparing the test.
The box contains enough swabs, test strips, and reagents to conduct 25 strep A tests.
The Areta Strep A Swab Test Kit also includes bottles of positive and negative control solutions. These allow you to perform a quality assurance check if you have any doubts about whether the test materials are valid or whether you are properly following the test instructions.
Preview – Strep A Test
Price: See best price on Amazon (25 tests)
Sample: Throat swab
Results timeline: Within 10 minutes
The Preview Strep A Test Kit is our pick for the at-home strep A test with the clearest instructions. It is a rapid antigen detection test that provides visual results in 10 minutes.
To take this test, start by mixing five drops of the two provided reagents in the medical-grade tube that is included in the kit. Rub the sterile swab that is included with the kit on the back of the throat. Then carefully take the throat swab and use the special extraction tube to obtain the maximum amount of material from the swab. Be sure not to place the swab on or touch any surface during this transfer.
After adding your sample to the tube, dip a test strip into the tube for exactly five seconds. The results are shown on the test strip ten minutes later and indicate whether the sample was positive or negative. (Note that the test strip may display an invalid result if the test was incorrectly prepared.) Positive and negative control samples are included to validate test quality.
Each Preview Strep Test includes enough tubes, swabs, strips, and reagent solution to carry out 25 separate strep A tests.
EZ Level – Strep A Test Kit
Price: $42.95 (25 tests)
Sample: Throat swab
Results timeline: 5 minutes
The EZ Level Strep A Test Kit follows a similar approach to other at-home strep throat tests, but it provides the fastest results. After preparing your test materials, the EZ Level test shows results in five minutes.
The test kit includes detailed instructions that make it straightforward to conduct this test for yourself or a child. Start by mixing an equal amount of the two reagents in the tube. Without touching the tongue, rub the sterile swab that is included with the kit on the back of the throat.
Then take the swab and place it in the tube, agitate it for exactly one minute, and finally squeeze it to mix the sample with the reagents. Be sure not to let the swab touch any surface during the transfer.
Once everything is mixed, dip a test strip into the tube, remove it, and then wait five minutes. At that point, you will know whether the test is positive or negative based on the number of lines displayed on the test strip.
Interpreting At-Home Test Results
Rapid at-home strep tests provide results within minutes. The results are displayed visually and indicate whether the test was positive or negative.
A positive test means that there is a strep A infection because antigens to strep A bacteria were found on the throat swab. If the test result is positive, you should contact your doctor, or, if you performed the test on a child, you should contact your child’s pediatrician.
In most cases, a strep A infection is treated with antibiotics that can decrease symptoms and prevent more serious complications. It is important to note that the doctor may want to repeat strep throat testing before prescribing antibiotics.
A negative result on an at-home strep throat test means that no strep A antigens were found on the swab. However, this does not guarantee that there is no strep A infection. Rapid testing is not perfectly accurate and does not always detect the infection. This can be influenced by errors in sample collection and a certain percentage of error in the test itself.
In many medical offices, testing for strep throat involves both a rapid test as well as a throat culture test, which usually provides results in a couple of days. Doing both tests can help assure that any active strep A infection is found. Guidelines from medical organizations for confirmatory testing depend on the patient’s age:
- In children, it is recommended that any negative rapid strep A test be confirmed with a throat culture test. recommend that any negative rapid strep A test in children be confirmed with a throat culture test.
- In adults, routine confirmatory testing is not recommended, but it may be used according to the judgment of the health care provider.
Unfortunately, this combination of rapid test and throat culture is not provided with at-home test kits. As a result, any person concerned about a possible strep throat infection should talk with a doctor.
Are test results accurate?
Rapid strep throat tests are a commonly used and important tool for detecting strep A infections. However, like all medical tests, they are not perfectly accurate.
One concern with rapid tests like those used for at-home strep testing is the possibility of a false negative result. In as many as 30% of cases, a rapid test may come back negative in someone who actually has a strep A infection. This is why many doctors prescribe a throat culture test along with a rapid test when the rapid test is negative.
Another factor that affects the accuracy of an at-home strep test is the preparation of the test sample. It is important to vigorously swab the correct parts of the tonsils and throat while avoiding contact with the tongue or other parts of the mouth. If this is done improperly, the test is less accurate in detecting a strep A infection.
Positive test results are rarely inaccurate. This means that a positive test usually accurately reflects a current strep A infection. That said, sore throat and other symptoms may be caused by a viral infection that occurs alongside an asymptomatic presence of strep bacteria in the throat. In these patients, antibiotics are unlikely to improve their symptoms. Tests alone typically cannot determine the cause of symptoms in these cases, which makes it important to be evaluated by a physician.
Do I need follow-up tests?
Follow-up testing is often necessary after an at-home strep throat test.
If an at-home strep A test is positive, it is important to contact a doctor who is likely to suggest a repeat test to confirm the results of the at-home test. This could include both a rapid strep test and a throat culture.
Although throat culture tests are considered to be the gold standard for detecting strep A infections, they are not always used in adults because strep A rarely causes major complications in adults.
If an at-home strep test is negative, follow-up testing may still be recommended by a doctor in order to confirm the results of the at-home test, especially if you have symptoms that are consistent with strep throat and not a viral infection due to the high rate of false negative result on rapid strep tests.
Questions for your doctor after at-home testing
If you’ve taken an at-home strep throat test, you can talk with a doctor about the test results. Some of these questions may be helpful in that conversation:
- Is my at-home test result reliable?
- Do I need any follow-up testing based on my at-home test result?
- Are my symptoms consistent with strep throat?
At-home tests are not the only way to detect a strep A infection. The following section describes some main differences between strep throat testing at home and at a medical office.
How does laboratory and at-home strep throat testing compare?
At-home strep throat tests use rapid antigen detection tests that are similar to those used in many medical offices. However, there are important differences between at-home and in-office strep A testing:
- Types of tests available: In a medical office, the doctor has the option of rapid strep testing and/or throat culture, which is generally considered to be more accurate in detecting strep A infections. For at-home tests, only rapid testing is available.
- Experience in sample collection: Doctors and nurses are trained to take a throat swab properly. This can help make sure that there are no errors that cause test inaccuracies.
- Training in test interpretation: Understanding the results of a strep throat test isn’t always as simple as seeing whether it is positive or negative. When taken by your doctor, test results can be most effectively interpreted within the context of your symptoms and overall health.
A.D.A.M. Medical Encyclopedia. Antigen. Updated July 11, 2019. Accessed July 28, 2021. https://medlineplus.gov/ency/article/002224.htm
A.D.A.M. Medical Encyclopedia. Strep throat. Updated July 11, 2019. Accessed July 26, 2021. https://medlineplus.gov/ency/article/000639.htm
A.D.A.M. Medical Encyclopedia. Streptococcal screen. Updated January 30, 2020. Accessed July 28, 2021. https://medlineplus.gov/ency/article/003745.htm
Centers for Disease Control and Prevention. Pharyngitis (strep throat). Updated November 1, 2018. Accessed July 27, 2021. https://www.cdc.gov/groupastrep/diseases-hcp/strep-throat.html
Centers for Disease Control and Prevention. Strep throat: All you need to know. Updated January 12, 2021. Accessed July 27, 2021. https://www.cdc.gov/groupastrep/diseases-public/strep-throat.html
Chow AW, Doron S. Evaluation of acute pharyngitis in adults. In: Aronson MD, ed. UpToDate. Updated September 21, 2020. Accessed July 26, 2021. https://www.uptodate.com/contents/evaluation-of-acute-pharyngitis-in-adults
Food and Drug Administration. FDA executive summary: Over-the-counter diagnostic tests for the detection of pathogens causing infectious diseases. Published August 16, 2016. Accessed July 26, 2021. https://www.fda.gov/media/99873/download
MedlinePlus: National Library of Medicine. Strep A test. Updated July 31, 2020. Accessed July 26, 2021. https://medlineplus.gov/lab-tests/strep-a-test/
Wald ER. Group A streptococcal tonsillopharyngitis in children and adolescents: Clinical features and diagnosis. In: Edwards MS, Messner AH, eds. UpToDate. Updated June 4, 2021. Accessed July 26, 2021. https://www.uptodate.com/contents/group-a-streptococcal-tonsillopharyngitis-in-children-and-adolescents-clinical-features-and-diagnosis