Flu testing

Influenza (commonly known as the flu), is a respiratory virus that tends to peak during the winter months. Because the symptoms of the flu can mimic other viral infections like COVID-19, it is important to get tested. Understanding when and how to get tested for the flu will help you get the right treatments, so you can get back to feeling your best!

Different kinds of flu testing

There are a few different types of tests used to detect influenza viruses, here is a closer look at the most common types of flu tests, as outlined by the CDC.

Rapid Influenza Diagnostic Tests (RIDTs)

The most commonly used tests, according to the CDC, are called rapid influenza diagnostic tests (RIDTs). An RIDT is an antigen test that detects if there is a portion of the flu virus in the body. RIDTs are rapid tests, usually giving results in about 10-15 minutes.

Unfortunately, because of the speed and type of these tests, RIDTs do not provide the highest accuracy, according to reports by the CDC. So even if you test negative, there is still a small chance that you could be ill with the flu.

Rapid molecular assay

Another type of flu test is called a rapid molecular assay. These tests look to see if any genetic material of the flu virus is present in the body. These are also fairly quick tests, usually yielding results within 15-20 minutes. However, the CDC notes that assay tests are a bit more accurate than the RIDTs.

Other types of flu tests

Additional types of flu tests, according to the CDC include reverse transcription polymerase chain reaction (RT-PCR) tests, viral culture tests, and immunofluorescence assays.

The RT-PCR tests look for the presence of nucleic acids in the body and are highly sensitive, making them the most accurate testing option. RT-PCR tests usually take about 15-30 minutes to give results.

Assay-based tests are typically used to help distinguish between different variants of the flu (like influenza A and influenza B), and take the longest to yield results according to the CDC.

Who should get a flu test and when?

Anyone who is showing symptoms after being exposed to the flu should get tested for it. Many times though, you will have no knowledge of any exposure. So it is best to get tested if you show any of the common flu symptoms during “flu season” (which is October to April for the United States). According to the CDC, common symptoms of the flu include:

• Fever above 100 degrees Fahrenheit
• Cough
• Sore throat
• Runny or stuffy nose
• Headache
• Muscle aches
• Chills
• Fatigue (tiredness)
• Nausea, vomiting, or diarrhea

It is worth noting that many people don’t ever get tested for the flu, because they are able to manage symptoms by resting at home, according to the CDC. So it is safe to assume that anyone experiencing these symptoms during flu season is capable of exposing others to the flu virus. If you are at a higher risk of complications that could be exacerbated by catching the flu, a healthcare practitioner may recommend more diligent screenings, tests, and precautions. People at a greater risk of complications from the flu, according to the CDC include:

• The elderly
• Those with a weakened immune system (due to things like cancer treatment or autoimmune diseases)
• Infants and children under the age of five
• Pregnant women
• Individuals with chronic illnesses (like diabetes, COPD, or asthma)
• Current sickness and/or hospitalization with another illness

Because the flu is a respiratory virus, the CDC warns there is a risk of developing severe complications from the flu. Pneumonia is an infection of the lungs that can have serious health repercussions if not properly diagnosed and/or treated. It is common in severe flu cases if treatment is delayed. For this reason, taking steps to protect yourself (like getting your annual flu shot) and getting tested if you have symptoms is recommended.

How to get a flu test

Flu tests are widely available throughout the country; however, access varies depending on location and socioeconomic status. Ultimately, if you are interested in getting a flu test completed, you should start by reaching out to a healthcare provider who can point you in the right direction. Alternatively, many local pharmacies and urgent care centers offer flu tests, so finding out which urgent care centers and pharmacies in your area offer testing is also an option.

Can I get a Flu test at home?

At-home flu tests are available, and instructions are included in these tests for how to perform them. There are two types of at-home tests available: rapid and self-collection. Rapid tests require you to swab your nose to collect a sample of mucus that is then mixed with a solution and placed on a testing stick. Self-collection tests require a mucus sample to be sent to a lab for testing. While the self-collection tests usually will require a longer wait time to obtain results, they are often a more accurate option than the rapid tests, according to the CDC

Cost of the Flu test

Flu tests may not be covered by insurance. However, the cost of most tests averages around $20 per test. This rate will vary slightly, depending on your location, so check with your local pharmacy and/or healthcare provider about the cost of testing in your area.

What to expect during a flu test

If you haven’t undergone the experience of getting a flu test, it is helpful to know what to expect ahead of time.

Before the flu test

There are no special instructions that you should follow to prepare yourself before going for or taking a flu test.

During the flu test

During the flu test, a sample of your nasal secretions is obtained. This sample is almost always collected through the nasal cavity. The most common sample collection technique involves using a nasal swab, according to the CDC. The depth of inserting the swab varies depending on the type of test and age of the patient.

A sample can also be obtained from the nasal cavity through a wash and aspirate technique. This involves a saline solution injected into the nasal cavity, then a healthcare provider will suction out the saline solution using gentle suction methods. This is most often used with young children.

The CDC notes that many people report feeling a gag and/or a tickling sensation during a flu test because of the sensitivity of the nasal cavity. These sensations are usually brief and resolve once the sample collection is over.

After the flu test

Results for the flu test take anywhere from a few minutes to a few days, depending on the type of test. Most flu tests in the medical setting yield results within a few minutes.

What to do if you test positive for the flu

While most people recover just fine from the flu, the CDC recommends that you still take precautions to avoid getting other people sick. If you test positive after getting a flu test, you should follow their guidelines for self-isolating yourself until you recover.

Current CDC guidelines recommend that if you test positive for the flu you:

• Isolate yourself to prevent spreading the sickness to others.
• Stay home until you are fever free without medicine for at least 24 hours.
• Wear a facemask if needing to go into public while sick.
• Monitor your symptoms and seek medical care if you begin experiencing severe symptoms such as difficulty breathing or a fever that goes away and then comes back.
• Contact your healthcare provider to learn about any treatment options that could help you recover faster such as antiviral medications or steroids.
• Wash your hands often while sick and while recovering. This is also good practice to help prevent getting sick again.

Remember, your healthcare provider can prescribe medications to help treat the flu. Several antiviral drugs are approved to fight against the flu virus. These are not sold over the counter, and not everyone benefits from them, so they require a physician's prescription.

Antiviral drugs work best when started soon after flu infection begins, according to the CDC, so it is best to seek testing and treatment as soon as possible after you begin experiencing symptoms.

These medications also can be helpful as they may reduce the risk of more serious complications from the flu, especially for those who are high-risk. In addition to lessening the severity and duration of some symptoms, these medications may also prevent the need for a hospital stay.

Because there are several options on the market, consult your doctor or go to a local urgent care center so that you are taking the appropriate medication and dose for your specific needs.

More about the flu

What is the flu?

The flu is a highly contagious respiratory illness caused by influenza viruses. According to the CDC, the flu can cause mild to severe illness—and can lead to complications that result in hospitalization or death in some cases.

How is the flu transmitted?

The flu viruses can spread from person to person through droplets made when people with flu cough, sneeze, or talk. People can also get the flu by touching a surface or object that has the flu virus on it and then touching their own mouth, eyes, or nose.

Flu symptoms to watch out for

Common flu symptoms according to the CDC include:

• Fever above 100 degrees Fahrenheit
• Cough
• Sore throat
• Runny or stuffy nose
• Headache
• Muscle aches
• Chills
• Fatigue (tiredness)
• Nausea, vomiting, or diarrhea

How is the flu diagnosed?

The flu can be suspected based on symptoms alone, however, only a flu test can accurately diagnose an active flu illness.