The antigen test, a new alternative to the PCR test?
Easier, faster (results are known between 15 and 30 minutes) than RT-PCR, it should be deployed en masse by the end of the month.
If the sample is also taken by swab in the nostrils, the antigen test no longer requires laboratory analysis.
Because instead of detecting the genetic material of the new coronavirus with an amplification method (which takes several hours) as is the case for PCR samples, it only identifies the proteins of the virus in a few minutes via a small strip that looks like to a pregnancy test.
If a purple line appears, the sample is positive.
If there is no staining, it is considered negative.
Only problem: it is less reliable than PCR, especially for low viral loads.
According to Jean-Michel Pawlotsky, virologist and head of the biology and pathology department at Henri Mondor hospital (Créteil), recent evaluations have however shown that the overall rate of sensitivity to the virus was estimated at 60%.
A figure that climbs to 80% when those tested have a very high viral load.
Make a first sort
The interest of this new device is therefore clearly to make a first screening, faster, between people negative for Covid-19 and those positive.
And to unclog analytical laboratories.
“The deadlines are much shorter and the protocol is easier,” explains Jean-Michel Pawlotsky.
These antigenic tests, which are intended to be applied on an outpatient basis, will be more useful for mass tests.
For example in airports, universities or in companies ”.
The Ministry of Health has even just paved the way for a wider deployment by issuing a decree which authorizes, conditionally, their reimbursement by Social Security for people with symptoms.
In a few weeks, a person with a fever with respiratory signs could be tested directly by their doctor.