At-Home Flu Testing
- Also Known As:
- At-Home Influenza Test
- At-Home Rapid Influenza Antigen Test
- At-Home Rapid Flu Antigen Test
Test Quick Guide
The flu is a contagious respiratory illness caused by influenza viruses which spread most frequently during the colder months of the year. While the flu causes only mild symptoms in many people, it can lead to life-threatening complications, especially for children, older adults, and other vulnerable groups with certain health conditions.
At-home flu tests use a nasal swab or saliva sample to test for the presence of an influenza virus. The test may help identify the cause of flu-like symptoms; however, the results of the test must be interpreted carefully and should be reviewed with a doctor.
About the Test
Purpose of the test
The purpose of at-home flu testing is to detect the presence of the flu virus. This can help determine if symptoms are being caused by an influenza virus and may help a doctor diagnose the flu. Quickly detecting an influenza infection can also enable measures to reduce the chances of spreading the virus to other people.
Some at-home flu tests use a nasal swab or saliva sample to also test for the SARS-CoV-2 virus, which causes COVID-19. The goal of this combined testing is to look for two separate viruses that can cause similar respiratory symptoms and may have the potential to trigger more serious complications.
What does the test measure?
There are different types of measurements that can be used in at-home tests to detect an influenza virus infection.
Some at-home flu tests measure whether there are any detectable proteins on the surface of the influenza virus called antigens. These viral antigens, when present in the respiratory tract, can then trigger a response from the immune system resulting in the flu-like symptoms. The presence of antigens on a nasal swab or saliva sample can be an indication of an influenza infection.
Another type of at-home flu test measures whether there are any pieces of the virus’s genetic material in your test sample and are known as molecular tests. One common type of molecular test uses technology known as reverse transcription polymerase chain reaction (RT-PCR).
When should I get an at-home flu test?
There are no strict guidelines or clear recommendations for when to take an at-home flu test.
In general, flu testing is only conducted when you have symptoms that could be caused by an underlying infection with an influenza virus. Testing is most often done when symptoms are significant or when you are at higher risk of flu complications because of your age, coexisting medical conditions, or pregnancy.
A flu test is often not necessary if you have only mild symptoms and flu transmission in your community is high. In these cases, testing may not be needed because it would not change the way you are treated.
If you have flu-like symptoms or are concerned about possibly having the flu, you should talk with a doctor. Since there are multiple factors involved in determining whether a flu test is appropriate, the doctor can address whether testing, including at-home testing, is recommended in your situation.
Benefits and Downsides of At-Home Flu Testing
To decide if at-home flu testing is a good fit for your needs, it’s important to consider its potential positives and negatives.
The main possible benefits of at-home flu testing include:
- Convenience: An at-home test can be ordered online and performed at home at your convenience without needing to make an appointment or go to a medical office.
- Testing in isolation: If you are worried about being contagious with the flu, at-home testing allows you to get tested while avoiding contact with other people.
- Option to test for flu and COVID-19: Some at-home test kits are able to test for both the flu and COVID-19 with one test sample.
- Transparent pricing: Most at-home influenza testing involves a single, all-inclusive price that is clearly shown before making your payment.
Some of the main possible downsides of at-home flu testing include:
- Limited test interpretation: Understanding the results of a flu test is not as basic as just seeing whether it is positive or negative. There may be some variability in at-home test results. Therefore, at home testing requires careful consideration of factors like the type of test kit used, your symptoms, and the extent of seasonal flu in your area. Test interpretation is best done by a doctor, but many at-home tests don’t offer detailed medical consultation.
- Potential sample collection errors: While test kits include detailed instructions, there is the potential for an invalid or inaccurate result if the test sample is not collected properly.
- Testing may not affect your medical care: In many cases, the results of an at-home flu test will not change the next steps in your care and recovery.
- Out-of-pocket cost: Insurance often does not cover at-home flu testing, requiring you to personally pay for the full cost of the test kit.
- Time delay on self-collection tests: If you take a test that requires sending your sample to a lab, it can take several days before you receive a result.
If you have questions about whether to have at-home influenza testing, you can talk with your doctor about how to evaluate its pros and cons in your specific case.
Types of At-Home Tests
There are two main types of at-home flu tests:
- Rapid antigen tests: These tests generally involve inserting a swab into your nostril. The sample can then be analyzed in your home with materials that are included in the test kit. Results are typically available in around 15 minutes.
- Self-collection molecular tests: These tests use a nasal swab and/or a saliva sample that you collect at home and then send to a laboratory to be analyzed. Instead of testing the sample for antigens, these tests use molecular techniques such as RT-PCR to look for traces of the influenza virus’s genetic material.
The following section describes the best at-home flu test that is currently available:
Best for Flu and COVID-19
myLAB Box – At-Home COVID-19 + Flu Viral Detection Test
Sample: Saliva or nasal swab
Tests for: Influenza A, Influenza B, COVID-19
Results timeline: Within 3 to 4 business days
The At-Home COVID-19 + Flu Viral Detection Test offered by myLAB Box uses molecular analysis to detect potential infections with influenza and SARS-CoV-2, the coronavirus that causes COVID-19.
To take the test, collect a sample of your saliva or swab the lower part of your nostrils and place the sample in a sterile tube. When using a swab, be careful not to contaminate it by placing it on a surface or touching it with your fingers. Then package it in a prepaid return mailer and send the sample to the company’s affiliate lab on the same day it was collected.
The laboratory utilizes viral RNA extraction and amplification and polymerase chain reaction (PCR) analyses to look for traces of the genetic material of SARS-CoV-2, influenza A, and influenza B. Detection of these viruses is a strong indicator of a likely infection.
The analyses are usually completed within 24 hours after the sample arrives at the CLIA-certified lab and the results are provided to you through the myLAB Box online health portal. If your test is positive, the company will arrange for a physician to contact you within 24 hours.
The price of the test kit includes overnight shipping to your home, as well as the cost of shipping your sample back to the lab.
Interpreting At-Home Test Results
For a rapid antigen test that is conducted at home, the results will typically be displayed visually on a small test card that is included in the test kit. After preparing the test, the result will be shown as positive, negative, or invalid.
For a self-collection molecular test, the test report will show whether your sample was positive, negative, or inconclusive after being analyzed by the lab.
If your test involves checking for influenza and other viruses, such as the coronavirus SARS-CoV-2, the test report should clearly show the results for each separate virus.
Interpreting the test result requires considering more than just whether it was positive or negative. Your symptoms, the prevalence of seasonal flu in your community, and the type of test are all factors that can influence whether your result actually reflects whether or not you have the flu.
A positive test result suggests, but does not definitively prove, that you have an influenza infection. If your test result is positive, you should contact your doctor to ask about next steps in your care. False positives, which show a positive result when you aren’t actually infected, can occur but are uncommon.
A negative test result means that the influenza virus was not present in the sample provided. However, it is important to consider whether the result could be a false negative, which means that you are infected even though the test found no sign of an influenza virus. False negatives are much more common with rapid antigen tests than with molecular tests.
In order to evaluate the accuracy of your at-home test and to understand its significance for your overall health, you should contact your doctor and review your symptoms and test result.
Are test results accurate?
At-home influenza tests are widely used to identify infections, but, like any medical test, not 100% accurate. Results are dependent on the following factors:
- Type of test: Depending on the reagents in the test kit, some tests may be more likely to produce inaccurate results. Generally, rapid antigen tests have a higher risk of false negatives than molecular tests.
- Extent of seasonal flu in your community: Your chances of exposure to an influenza virus are higher when the flu is widespread in your area. As a result, false positive results happen more often if community flu transmission is low, whereas false negative results occur more frequently when community spread is high.
- Test timing: Tests are more likely to correctly detect an infection if your test sample is taken during the first two to four days after you notice the signs and symptoms of flu infection. This is when the virus is present in higher amounts. After this point, you may test negative even if you have been infected.
- Proper test sample collection and handling: A test cannot return an accurate result if the test sample is not properly collected and properly prepared for testing. It is important to only provide the kind of sample stipulated in at-home test instructions. You must also be careful to handle the sample and carry out the test as directed by the test kit instructions. If a laboratory analyzes your self-collection test, the laboratory professionals will follow required procedures to ensure the integrity of the test sample and accuracy of the test result.
- Certain flu vaccines: If you receive a type of flu vaccine that has a weakened version of the virus, it may cause a positive result on a RT-PCR test taken within a week after vaccination. This is a false positive result because the vaccine does not cause a true viral infection.
Since multiple factors can be involved in interpreting the accuracy of influenza testing, it is best to discuss your at-home flu test result with a doctor who can explain how these factors apply in the context of your specific test outcome.
Do I need follow-up tests?
The need for follow-up tests depends on your test result, your symptoms, and your overall health.
If you have a positive test result and only mild flu symptoms, you may not need any further testing. However, if you have more serious symptoms or are at risk of developing complications from influenza, the doctor may want to do repeat flu tests, blood tests, or perform examinations of your lung function.
If you have a negative test result but have symptoms of the flu, you may need to have follow-up with another flu test to confirm that you don’t actually have influenza. For example, a negative rapid antigen test may need to be confirmed with a molecular test that is conducted in a laboratory.
Questions for your doctor after at-home flu testing
If you’ve recently taken an at-home flu test, the following questions may be useful to discuss with your doctor:
- How do you interpret my test result?
- Do you think the at-home test that I took was accurate?
- Should I have any follow-up testing?
- Are any treatments or other measures appropriate given my symptoms and test result?
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