How Do I Know If I Have Flu
Your respiratory illness might be influenza if you have fever, cough, sore throat, runny or stuffy nose, body aches, headache, chills and/or fatigue. Some people may have vomiting and diarrhea, though this is more common in children. People may be sick with flu and have respiratory symptoms without a fever. Flu viruses usually cause the most illness during the colder months of the year. However, flu can also occur outside of the typical flu season. In addition, other viruses can also cause respiratory illness similar to flu. So, it is impossible to tell for sure if you have flu based on symptoms alone. If your doctor needs to know for sure whether you are sick with flu, there are laboratory tests that can be done.
Is There A Test For The Flu
Yes! You should get a flu test as soon as possible, preferably within four days after first experiencing symptoms. Its important to get a flu test because detection of influenza virus can reduce unnecessary laboratory testing for other infections and stop inappropriate antibiotic use. It will also encourage the effectiveness of infection prevention and control measures and increase the appropriate use of antiviral medications.
Several tests can detect the influenza virus, but only two are recommended by the Infectious Diseases Society of America for use in non-hospitalized people:
- Rapid molecular assay, also called a nucleic acid amplification test
- Rapid influenza diagnostic test , also called an antigen detection test
While the RIDTs are more common, rapid molecular assays are preferred by experts over RIDTs because they are more accurate.
Youll see other types of tests mentioned, such as real-time reverse-transcription polymerase chain reaction , viral cultures, or serologic testing, but these are best used in hospitalized patients when a quick result is not required.
When To Consider Further Influenza Testing
Consider sending respiratory specimens for influenza testing by viral culture or RT-PCR to confirm results of an RIDT when:
- A patient tests negative by RIDT when community influenza activity is high and laboratory confirmation of influenza is desired.
- A patient tests positive by RIDT and the community prevalence of influenza is low, and a false positive result is a consideration.
- A patient has had recent close exposure to pigs or poultry or other animals and novel influenza A virus infection is possible See Avian Influenza: Information for Health Professionals and Laboratorians for more information.
Hospitalized patients
Detection of influenza virus infection and prompt implementation of infection prevention and control measures is critical to prevention of nosocomial influenza outbreaks. When there is influenza activity in the community, clinicians should consider influenza testing, including viral culture, for patients who develop signs and symptoms of influenza while they are in a health care facility. This should be done as part of a broader surveillance strategy for influenza as discussed in Prevention Strategies for Seasonal Influenza in Heath Care Settings.
Suspected influenza institutional outbreaks
Influenza Surveillance
Don’t Miss: Valid Reasons To Decline Flu Vaccine
Getting Tested For Influenza
Tests for influenza infection are often ordered by a doctor and conducted in a hospital, doctors office, or laboratory. Rapid flu tests may also be done in outpatient settings like health clinics or pharmacies.
Testing for influenza normally involves a swab of the area in the back of the nose, the inside of the nostril, and/or the throat. For most people, obtaining a sample is not painful and can be done in under a minute.
In addition to flu swabs, testing can be done with nasopharyngeal aspirates, which are samples removed through the nose with a suction device. Because they are more difficult and uncomfortable to obtain, nasopharyngeal aspirates are not commonly used for diagnostic testing.
The only type of flu testing that does not use a sample from the respiratory tract is serology testing, which is not used for flu diagnosis. Serology tests require a blood sample that is typically taken from a vein in the arm.
Stock Up For Flu Swab Tests
With flu season underway, its crucial for clinics, hospitals and diagnostic labs around the world to keep in stock the highest quality specimen-collection products available. After all, the best defense is a good offense. As health care professionals know, the best way to help prevent the spread of the flu is with accurate, fast diagnosis and immediate treatment.
For additional insight on performing a flu swab test, .
To learn more about how Puritan products can help you meet your flu testing needs, please contact us today.
You May Like: What Medication Should You Take For The Flu
If You Don’t Have Symptoms But May Have Been Exposed To Covid
Say you were at a dinner party, the gym or working in the office with someone who ended up testing positive a day later. Even if you don’t have symptoms, those are situations in which you should take a test a few days after the exposure and quarantine yourself until you’re in the clear, according to the CDCs guidelines.
But if your rapid test result is negative, should you trust that result? Rapid antigen tests are generally less accurate when detecting COVID-19 cases in people who dont have symptoms, so this is where it gets tricky.
The experts told TODAY that, if there’s any way to do so, you should really opt for a PCR test in this scenario instead of a rapid test.
“If you are asymptomatic and you’ve been exposed and you want to see if you’re turning positive or not, I would recommend using a PCR methodology simply because it’s going to be more specific and more sensitive,” Volk said. “It’s just going to work a little bit better.”
That doesn’t mean the rapid tests are useless. It just means that, if you have the option to get a PCR under these circumstances, you should go with that.
If truly all you have access to is rapid tests, they can still be helpful. But you should then rely even more on other precautions, like wearing a high-quality mask or holding your gathering outside, to further reduce the risk of spread, Mathers said, especially if you’re spending time with people at high risk for severe COVID-19.
Related:
What Kinds Of Flu Tests Are There
A number of tests are available to detect flu viruses in respiratory specimens. The most common are called rapid influenza diagnostic tests . RIDTs work by detecting the parts of the virus that stimulate an immune response. These tests can provide results within approximately 10-15 minutes but may not be as accurate as other flu tests. Therefore, you could still have flu, even though your rapid test result is negative. Other flu tests called rapid molecular assays detect genetic material of the flu virus. Rapid molecular assays produce results in 15-20 minutes and are more accurate than RIDTs.
In addition to RIDTs and rapid molecular assays, there are several more accurate flu tests available that must be performed in specialized laboratories, such as those found in hospitals or public health laboratories. These tests include reverse transcription polymerase chain reaction , viral culture, and immunofluorescence assays. All of require that a health care provider swipe the inside of your nose or the back of your throat with a swab and then send the swab for testing. Results may take one to several hours.
Read Also: Pain In Arm After Flu Shot Weeks Later
What To Do After Getting Test Results
If you use a COVID-19 rapid test or have received a lab test, you need to know what to do with your result.
If your test result is positive:
- immediately isolate yourself away from others, including those in your household, and follow the advice of your local public health authority on isolation requirements
- and was from a COVID-19 rapid test, contact your local public health authority to determine whether laboratory confirmatory testing is available
- and you have symptoms that are getting worse, contact your health care provider
If your test result is negative, you may still be in the early stages of infection and can potentially infect others, so you need to:
- follow the instructions contained in your test kit and advice from your local public health authority about how soon after you should re-test
- isolate yourself if you have any COVID-19 symptoms and follow advice from your local public health authority on additional testing
- quarantine if you have been exposed to COVID-19 and your local public health authority recommends this
- continue to follow all public health measures, including:
- staying home when sick
Why Is The Flu Such A Big Deal
The flu is an important general and public health concern because it can be deadly and because every few decades an especially lethal influenza strain emerges. The worst on record is the 1918 Spanish flu pandemic, which killed 20 to 50 million people worldwide, and more than 500,000 in the United States alone. In 1957 and 1968, hundreds of thousands died in the U.S. from Asian and Hong Kong flu variants.
In more recent years, there has been international concern about the H5N1 and H7N9 subtypes of influenza A, commonly called avian flu, and H1N1 flu. Some of these subtypes have caused outbreaks in humans, and there is concern that they may in the future cause more widespread and serious outbreaks. Read the article on Influenza to learn more about these.
Don’t Miss: Drive Through Flu Shots 2021
You Don’t Actually Have Influenza
If your rapid test comes back negative, it is possible that you do not have influenza. Flu-like illnesses can be caused by other viruses that cause more severe symptoms than a cold. Viruses such as adenovirus, coronavirus, parainfluenza, and respiratory syncytial virus can cause all of the miserable flu symptoms, but do not respond to antiviral medications that are effective against influenza.
While these viruses can certainly leave you feeling awful for a few days, they are less likely than influenza to lead to serious complications, secondary infections, or death.
Workplace Rapid Testing And Screening
The Government of Canada, some provincial/territorial governments and distribution partners are also providing COVID-19 rapid tests to businesses and organizations. This provides an extra layer of defence against the spread of the virus, which helps keep employees and communities safe.
Learn more about how to get tests for your workplace .
Read Also: How Much Does The Flu Shot Cost At Target
Types Of Influenza Tests
The first step in diagnosing influenza is almost always a physical examination that includes a review of any active flu-like symptoms. During seasonal flu epidemics, additional testing beyond a physical exam may not be needed to diagnose influenza.
When other tests are needed, they focus on identifying signs of an influenza infection. There are several different tests that can check for the presence of an influenza virus. The choice of which test to prescribe depends on the purpose of testing, how quickly results are needed, test availability, and laboratory capabilities.
One important way that influenza tests can be categorized is based on where the analysis is conducted:
- Rapid, point-of-care tests, sometimes called rapid influenza diagnostic tests , are able to determine whether the test is positive or negative without sending the sample to a lab. These tests usually provide results within 10 to 30 minutes. The design of these tests allows them to be used in many settings including doctors offices, health clinics, and pharmacies.
- Laboratory tests require that the sample be analyzed using equipment or methods that require the use of a medical lab. These tests often take several hours to complete and are not as widely available as rapid tests.
Another important way of categorizing tests is based on how they detect signs of an infection:
Antigen testing can also be done in a laboratory. Laboratory-based antigen testing can take longer but may provide more accurate results.
How Accurate Is A Rapid Flu Test
A rapid antigen flu test is the least accurate type of flu test. They have moderate sensitivity and high specificity.
Sensitivity refers to a test’s ability to determine that you have a disease or illness youre positive for the illness. The specificity of a test is its ability to determine that you dont have a disease or illness youre negative for the illness.
A highly sensitive test means that there are few false-negative results, meaning fewer cases of illness are missed. Since a rapid flu test has moderate sensitivity, its more likely that itll have a false-negative result and miss positive cases. High specificity means that false-positive results are rare.
You May Like: How To Tell If It’s A Cold Or Flu
Where Can You Get A Flu Tests
Flu tests are available at most doctors offices, urgent care settings, and hospitals.
Rapid flu tests are usually less costly than laboratory-based tests. According to Beckers Hospital Review, rapid tests cost about $5 to $10, while a laboratory test can cost $200 or more.
You may wish to contact a facility where youre seeking testing to ensure they have flu tests available, especially if youre in flu season, which usually takes place in the late fall to winter.
Will My Health Care Provider Test Me For Flu If I Have Flu
While your doctor may test you for flu, not everyone who goes to the doctor with flu-like symptoms will be tested. After evaluating you, your doctor may choose to diagnose you with flu without the need for testing based on your symptoms and his or her own clinical judgement.
Please visit diagnosing flu for more information.
You May Like: How To Get Checked For Flu
How Is A Flu Test Performed
All flu tests require a respiratory sample. This can include samples from:
- Your nasal cavity with a swab.
- Your nasal cavity through a wash or aspirate, meaning your healthcare provider injects a saline solution into your nose and removes the sample with gentle suction. This collection method is sometimes used on very young children.
- The upper part of your throat with a swab through your nose.
If You Have Symptoms But Your Rapid Test Is Negative
As mentioned above, if you have symptoms and test positive on an at-home test, you should assume those results are generally correct and take the appropriate steps to isolate.
“The problem is: If it’s negative, it doesn’t mean the person doesn’t have COVID,” Garner said. “They just may not have a high enough amount of virus to turn a rapid test positive.”
With the omicron variant , it generally takes about three days from exposure to start feeling symptoms, he added. And keep in mind that symptoms can include obvious things, like fever, as well as things like a runny nose and fatigue that can be confused for allergies or a cold.
So if you have any of these symptoms but test negative, Garner recommended taking another rapid test 48 to 72 hours later. At that point, if you do have COVID-19, you have a better chance of testing positive because you’ll have a larger amount of the virus in your system. If the result of that test is also negative, you can be more confident that you don’t actually have COVID-19.
Despite their advantages, the rapid tests “come with a lot of caveats around not being as sensitive early in infection, even if you’re infectious,” Mathers said. “So repeating a test is a way to kind of compensate for the lack of sensitivity.”
Related: How to properly store your at-home COVID-19 rapid tests
Also Check: Flu Vaccine Prices At Walmart
Should I Get A Flu Shot
The Centers for Disease Control and Prevention recommends that everyone 6 months old and older get a flu shot each season. In particular, people who are at high risk of complications from the flu should receive the vaccine. These include young children, the elderly, residents of nursing home and other long-term care facilities, pregnant women, and people with pre-existing conditions such as asthma, COPD, heart disease, and liver or kidney disorders.
Interpretation Of Rapid Influenza Diagnostic Test Results
Proper interpretation of RIDT results is very important for clinical management of patients and for assessing suspected influenza outbreaks. A number of factors can influence the results of RIDTs. The accuracy of RIDTs depends largely on the conditions under which they are used. Understanding some basic considerations can minimize being misled by false-positive or false-negative results.
Positive result
Negative result
- A negative result means that the RIDT did not detect any influenza viral antigen.
- The negative predictive value of an RIDT is highest when influenza activity is low in the population being tested .
- A negative result is most likely a true negative result if the respiratory specimen was collected close to illness onset during periods of low influenza activity in the population being tested .
- The negative predictive value of an RIDT is lowest when influenza activity is high in the population being tested .
- False-negative results are more likely to occur when influenza prevalence is high in the community.
Minimize False Results
You May Like: Cvs Pharmacy Flu Shot Appointments
Which Is The Best Influenza Swab
Clinicians have several options in swabs when it comes to performing a flu swab test, but not every swab will generate the same level of accuracy. For maximum specimen access, swabs should be transported using appropriate transport media.
Swab options for flu testing include flocked swabs, cotton tipped swabs, rayon tipped swabs, and foam tipped swabs.
Some Things To Know About Covid Rapid Tests
This article was originally posted in the Montreal Gazette
Starting this week, Quebecers are able to get rapid test kits from pharmacies so that they can test themselves at home. Compared to going to a test centre where lineups are starting to stretch into hours-long waits, the convenience of an at-home kit is obvious. The tests can be done anywhere and are easy to perform. Everything you need is in the testing kit. They are less expensive than PCR tests and provide results in 15 minutes. On the surface, the appeal of these tests should be obvious, and yet their rollout here has been slow compared to other countries, especially in Europe, where they have been widely used for months.
The fear has been that these rapid tests would be less accurate than standard PCR tests. But to truly evaluate their usefulness we have to look at both their sensitivity and their specificity. A sensitive test would correctly identify everyone with COVID-19 as positive. A specific test would correctly identify everyone without COVID-19 as negative. Ideally, you would want a test to be both sensitive and specific, but practically speaking you often must sacrifice one for the other. The issue with rapid tests is an issue of sensitivity. In other words, some people with COVID-19 do not test positive.
You May Like: 24 Hour Flu Like Symptoms