The Federal Audit Office has found gaps in controls of a free coronavirus testing system that contributed to an estimated CHF20 million ($21.5 million) in fraudulent invoicing.

Some 23 million free PCR and antigen tests have been carried out in Switzerland since the outbreak of the pandemic in 2020.

But it is widely believed that the system was scammed by fraudsters who worked with some doctors and testing centres to send out batches of fake bills to health insurers.

On Thursday, auditors said they had found two main weaknesses with the free testing system that helped fraud go undetected.

Firstly, health insurers did not send statements to all people who were tested, which made it harder to tell real tests from fakes.

Secondly, invoice reference numbers did not indicate which canton particular tests had been carried out. This makes it more difficult to trace the relevant testing centre.

Investigators have a five-year window to track down fraudsters and have so far only recovered CHF6,000, Swiss public broadcaster SRF reports.

The Federal Office of Public Health (FOPH) has identified 30 possible cases of serious fraud. Some 15 FOPH staff are trying to recover funds along with external consultants.

Free Covid-19 testing will come to an end in Switzerland from January 1, 2023.

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