You can experience a runny or blocked nose when you wake up one fine, chilly morning. You suspect the seasonal flu. But it doesn’t necessarily have to be that.
Contrary to popular belief, flu can strike at any time of the year and not just during the winter or influenza season. A common cold or a respiratory condition cannot be mistaken for the flu based solely on symptoms. The CDC advises getting a quick flu test to know for sure.
Let’s discover more about rapid flu tests to help you through the process.
A Brief Overview Of the Rapid Influenza Diagnostic Tests (RIDT)
These immunoassays assist medical professionals in determining whether the influenza virus is present in a patient’s respiratory material. The outcomes are either “good” or “negative.” Due to the clinically relevant period, these tests are known as rapid tests. An RITD typically takes fifteen minutes to produce findings. The sample taken from the respiratory system is examined for any viral antigens present. Additionally, a RITD also helps distinguish between influenza A and B.When Should You Take The Test?
The majority of us frequently mistake cold symptoms for flu symptoms. This test won’t help identify a regular cold. It’ll only help detect influenza A or B. Here are some common signs of the influenza A or B virus.- Muscle aches, exhaustion, or fatigue
- Experiencing lethargy and weakness
- Vomiting and diarrhea
- Headacheand chills together with a fever
- Sore throat
- Cough
- Runny or blocked nose on and off
- Abdominal pain
- Eye socket discomfort and pain around the eyes
How Is The Test Conducted?
You should get a RITD as soon as you see the symptoms appearing. You’ll get accurate results within four days after the spread of the flu. However, for immunosuppressed patients or younger children, influenza may be detectable for extended periods. A digital reading device and analyzer help examine the specimen and acquire the results. This device’s function is to give the information more specificity and sensitivity. There are two ways to collect the patient’s specimen. The samples can either be taken from the patient’s nose or throat with a swab or by the laboratory worker administering a saline injection into the person’s nose and gently sucking out the same solution. This is known as the nasal aspirate method.How Does This Test Perform Against Other Methods?
Reverse transcription-polymerase chain reaction, or RT PCR, is another method used in the medical sector. The quick flu test’s sensitivity to identify influenza A and influenza B viruses must be at least 80% higher than the RT PCR to get the results. Contrarily, the FDA states that a 90 percent sensitivity threshold is necessary when compared to viral culture. The FDA also establishes standards for the necessary degrees of specificity. The specificity value should be 95% when compared to RT PCR. Viral cultures have the same value. The fast flu test won’t be regarded as FDA-approved unless these requirements are satisfied.
How to Interpret the Findings?
Even though positive findings are simpler to understand, it is always the negative results that raise questions. Both numbers depend on how active the flu is among the patient group. You need to be aware of the following variances in the results:- False-Positive Or True-Negative
- False-Negative Or True-Positive
Factors Affecting RIDT Results
The accuracy of RIDTs can be affected by a variety of circumstances, including:· Influenza-Like Symptoms and Signs in the Clinical Setting
The chances of a positive RIDT result increases when there are symptoms similar to that of influenza due to an increase in the pre-test probability of influenza virus infection.· Duration of Illness before Collecting Respiratory Samples for Testing
It is more likely that testing samples obtained 3–4 days after the commencement of the illness—when influenza virus shedding is at its peak—will produce positive RIDT results.· Influenza Activity Prevalence in the Tested Population
Seasonal variations in influenza activity directly impact the RIDTs’ prediction powers.