Covid: the cold can skew PCR and antigen test results

Published by Graziella L. · Photos by Cécile D. · Published on 31 January 2022 at 16h25
With the winter temperatures France is experiencing, PCR and antigen test results performed outside can be skewed because of the cold, pharmacists warn.

As many French people keep on getting tested in pharmacies, the health authorities warn results can be skewed because of the winter weather. It can be the case is a PCR or antigen test is conducted in a tent, in front of pharmacies, in the cold weather.

Below 7 degrees Celsius (44.6°F), tests are more likely to lead to false positives because of the chemical reaction when adding the diluent cannot happen properly. The Union des syndicats de pharmaciens d’officine (Union of union trades of dispensary pharmacists) reminded that tests – self-tests included – should be kept between 2 and 30°C (35.6 and 86°F), safe from the sunlight, and cold.

Although some pharmacists can quickly get in back the dispensary to place the diluent in the test hole, this is not the case for all of them. A genuine issue as the cold has settled in the country. Union des syndicats de pharmaciens d’officine spokesman Gilles Bonnefond told BFMTV that “tests should not be stored in these tents” because “the test should be performed at room temperature, within the pharmacy”. But, as for sampling in the tent, there is no problem.

To control these tents better, the regional health agency announced they will reinforce controls and ask for a reference health professional to be always near the test tents.

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