Hundreds of thousands of Covid tests are conducted in France every single day.
Many of them are the rapid-result antigen tests conducted in tents set up in the street, often found just outside pharmacies.
While getting a test is straightforward enough, results obtained via an antigen test in cold conditions should be taken with a pinch of salt, according to health authorities.
More than a year ago, the French Health Ministry warned of false positives arising from antigen tests taken outside.
Inaccurate results can occur when temperatures drop below 2C because cold temperatures can influence the chemical reaction that takes place when the solution mixed with your nasal swab sample is entered onto the small plastic test reader.
Over the winter period, this means that there is a greater risk of inaccurate Covid test results. In the east of France, temperatures reached -3C on Thursday.
In an interview with Le Parisien on Thursday, the head of a French pharmacists union, Gilles Bonnefond, said there are two ways to avoid false results.
“The first is to not store the tests in the cold. The advice is to keep the the temperature between 2C and 30C. If the tests are frozen, it completely degrades the silicon mould,” he said.
Bonnefond said that while the tests can be carried out in tents where the temperature is lower, they should be moved to a space where it is at least 7C-8C while waiting for results.
He also warned that self-tests should not be stored in cold temperatures prior to use.
“Users must keep their tests at an ambient temperature. The worst thing is to leave them in the car where it can be very cold,” he said.
In France, you are encouraged to take a confirmatory antigen or PCR test if you have tested positive for Covid via a self-test. You can more about that HERE.
You are also encouraged to get tested if you have come into contact with someone who has Covid and have not been infected within the past two months.
You can find a full list of testing sites here.