The State’s medical devices regulator has said one of the most commonly used Covid-19 rapid antigen tests should be removed from the shelves after hundreds of users complained about false positive results.
The Health Products Regulatory Authority (HPRA) was acting on reports from medical professionals and members of the public over the performance of the Genrui antigen test.
Many reported testing negative on a PCR test or an antigen test from another manufacturer after testing positive using the Genrui kit.
The regulator has received more than 550 complaints from consumers since The Irish Times first highlighted the issue this week.
The HPRA said in a statement on Wednesday that retailers were removing the product from sale on a voluntary basis pending further investigation.
It said: “The rapid rise in the number of reports of false positive results relating to the Genrui self-test is significant and a precautionary removal from sale is warranted while the matter is further investigated by the manufacturer [Genrui Biotech] and its European representative.”
Responding to the issues raised in Ireland, a Genrui Biotech spokesman said antigen self-test kits "cannot be used alone for the diagnosis of SARS-CoV-2 infection" and should be combined with other information, such as a PCR test, to determine whether a user is infected.
He defended the performance of the kits, saying it complies with all relevant quality standards and safety requirements.
The accuracy of test results depends on a variety of factors, including standardised sampling, the time of result interpretation, ambient temperature and operating procedures, he said. “Users are advised to strictly follow the instructions to reduce the possibility of inaccurate results.”
Genrui Biotech said it was working closely with local agents in Ireland to “actively investigate” the product batches which were the subject of complaints here.
"We are also maintaining active communication with users who submit queries to us to ensure the proper handling of the related issues," a spokesman for the company, based in Shenzhen, China, told The Irish Times.
The HPRA does not approve antigen tests on sale in Ireland, but kits sold in the EU must conform with EU legislation and have been certified by an approved body in one of the member states.
The Genrui brand is sold in supermarkets such as Dunnes Stores and Lidl.
They are marked CE1434, indicating they were certified by the Polish Centre for Testing and Certification.
It has not received “negative feedback from the market” about the test, a spokeswoman said, but will take appropriate action if it receives official notification from a supervisory body.
Large numbers of people had taken to social media in recent days to say their positive result using the Genrui test was not confirmed when they went for a PCR test.
Some of the complaints related to the interpretation of a faint upper line on the test. Genrui, in the instruction leaflet included in every kit, advises users to “look very closely” as the control and test lines on the kit, as the T line (test) can be very faint.
“Any pink/purple here indicates a positive result,” the leaflet states.