Status: 04.12.2023, 08:32 a.m.
By: Simon Stock
With the cold season, Corona returns. Many people still have older rapid tests in their cupboard. But can you still use them?
Hamm - Coughs, runny noses, hoarseness: Pathogens are in high season in autumn and winter. But which one is it? Corona, RS virus and the classic flu differ in some symptoms, but not in all. After all, the coronavirus can be easily detected by a rapid test, as there are still enough of them lying around on the shelves at home from the peak phase of the pandemic. But can old corona tests still be used at all? Do they recognize the new variants?
Durability and new variants: Do old corona tests still work reliably?
Not only food has an expiration date, but also medical devices. There are usually two pieces of information on the packaging of Corona rapid tests. One mentions the date of manufacture and the other the expiration date. As a rule, there are twelve months in between. This means that tests can be kept for one year from the date of production, provided that they have been stored correctly. A temperature between 5 and 30 degrees Celsius is recommended. Or to put it another way: Tests do not belong in the refrigerator and not in the summer sun.
"The approved tests have an expiration date on the package. This is often reliable," says Dr. Ulf Dittmer, head of the Institute of Virology at Essen University Hospital, in response to an inquiry from wa.de. "However," Dittmer adds, "some manufacturers had problems with the liquid in the tubes drying up before the expiration date. Then, of course, such a test can no longer be used." So the problem is easy for users to see.
The case is different if the corona test is feasible but shows an incorrect result. The reliability of a test can suffer from improper storage or too long. True, a set is not immediately unusable once the expiration date has passed. But the longer the test has been in the cupboard, the greater the risk that it will no longer work properly. The German Pharmacists' Association therefore advises: "Expired tests should no longer be used, as their result is not reliable." By the way: If the T-line appears only pale and thin on the Corona test, this is not a malfunction, but has a clear message.
Eris and Pirola: Are the variants also detected by older corona tests?
Since the outbreak of the Corona pandemic at the end of 2019, not only has the world moved on, but the virus is no longer the same. Over time, new variants and mutations were added. There are currently two variants in circulation in Germany:
Ice scraping on the car: Home remedy frees icy windows in seconds
Customer orders new tablet from Amazon on Black Friday: When she opens box, the blow hits her
Bakery customer shows bill for six rolls: "Don't buy from the bakery anymore"
It's not just heating: homeowners will face a number of new obligations in 2024
Contamination detected: Manufacturer recalls UHT milk from Edeka
Fancy a voyage of discovery?
- Eris (EG.5)
- Pirola (BA.2.86)
Will they also be detected by corona tests? "The tests actually all detect Eris, because the change in the N protein is not large here," says Dr. Ulf Dittmer. "However, Pirola also has some mutations in the N protein (not only in the spike), so it is possible that some tests cannot detect this variant," says the chief virologist from Essen. Unfortunately, there is no exact data on this.
When asked, Dr. Carsten Watzl, Professor of Immunology at the University of Dortmund, explains: "I don't know of any data that would show that the tests would not work with the current variants. But, as always, it depends on the viral load and the quality of the swab." An instrument from the height of the Corona pandemic is about to return. Soon, patients will be able to get sick leave from their doctor by phone again - but only under certain conditions.