The rapid diagnostic orientation test (TROD) of influenza is feasible in pharmacyat the doctor’s office, or in a medical laboratory to screen for influenza A or B viruses. Without prescription, it consists of a sample taken from the nose and must be done within 24-48 hours after first symptoms appear suggestive of flu (sudden fever above 39°C, headache, body aches, sore throat, cough, extreme fatigue). As a reminder, each year in France, on average, 2 to 6 million people have influenza-like illness.

Definition: what is a TROD flu test?

The flu test is a rapid diagnostic orientation test or TROD. It detects the flu virus in a patient via a swab in the nose. It identifies viral types (influenza A and B), but does not discriminate between type A virus subtypes. This test is only recommended during an epidemic, in other words during periods of intense circulation of the influenza virus (autumn/winter) in order to quickly start antiviral treatments and reduce the risk of complications from influenza and interrupt transmission of the virus. It is particularly recommended in communities or health establishments (EHPAD, FAM, MAS) but also for people at risk such as the elderly, frail or pregnant women. It is of no interest outside of these indications (in city medicine for example) because of its low sensitivity, reports the Ministry of Health in a practical Guide published in 2019.

Where to do a flu test?

Unlike self-tests, TRODs cannot be performed only by health professionals duly trained. For instance :

• In pharmacy
• At the doctor
• In a medical laboratory
• To the hospital

Can we do a flu test in a pharmacy?

Yes. Since 1^er August 2016, the community pharmacist is authorized to carry out the oropharyngeal test for the diagnostic orientation of influenza, recalls theNational Order of Pharmacists.

The flu test consists of a nasal swab. The doctor or pharmacist takes a respiratory sample by inserting a kind of “cotton swab” in the nose of his patient. The analysis of this sample, which contains potentially contaminated cells, then makes it possible to determine the type of virus present (influenza A or B), can we read on the Institut Pasteur website.

How long does it take to get the results of a flu test?

TROD flu tests guarantee a rapid result in about twenty minutes.

How reliable is the flu test?

A negative test, meanwhile, does not exclude the diagnosis of influenza.

A positive test indicates that influenza A or B viruses have been found in the patient’s body. A negative test, meanwhile, does not exclude the diagnosis of influenza. The Ministry of Health reports of “many false negativesand a limited sensitivity of these tests, which is around 60%“. And to clarify “a negative result may indeed result from a level of antigens below the detection threshold of the test (due, for example, to an incorrect sampling procedure or sampling too late in relation to the onset of the disease)“If diagnostic certainty is necessary, a negative result should lead to continue the investigation with laboratory tests (PCR)

What is the cost of the flu test and is it reimbursed?

When performed in pharmacies, the TROD test costs between 6 and 7 euros and is reimbursed up to 70% by health insurance. The TROD flu test does not require a medical prescription.

Sources: National Order of Pharmacists / Institut Pasteur / PRACTICAL GUIDE RELATING TO SEASONAL INFLUENZA PREVENTION AND CONTROL MEASURES, Ministry of Health, July 2019 / Test and self-test: pricing methods change from November 1, Health insurance, 31 October 2022 / ARS Hauts-de-France