LONDON (AP) — Swiss pharmaceutical firm Roche said Wednesday that problems at a U.K. warehouse are delaying shipments of testing products to clinics and hospitals, triggering concerns that COVID-19 testing may be disrupted as infection rates rise around Britain.

Roche informed doctors about the problem at its U.K. distribution center in Sussex, southern England, in a letter that advised customers to “prioritize essential services only.”

Roche said the problem arose after it moved to a new automatic warehouse in September.

The company said that it was “prioritizing the dispatch of COVID-19 PCR and antibody tests and doing everything we can to ensure there is no impact on the supply of these” to the National Health Service.

The glitch affects materials needed to conduct blood tests and screening for diseases including diabetes and cancer. Roche said it could take two weeks to fix the problem.

British doctors have already raised concerns about the number of procedures, tests and screening programs that were put on hold as the health service focused on battling COVID-19 earlier this year.

While normal service has begun to resume, there is still a backlog, and long waiting lists for non-emergency operations.

Britain, which already has the highest virus death toll in Europe at over 42,500, is now facing a second surge in coronavirus cases. A total of 2,883 coronavirus patients were in U.K. hospitals on Tuesday, up from 2,291 a week earlier. A further 76 deaths of people with COVID-19 were recorded Tuesday, compared to 41 a week earlier.

Both figures are well below the peaks seen at the height of the U.K. outbreak in the spring.

Scotland is set to announce tightened social restrictions Wednesday in an attempt to slow the spread of the virus, and the British government is considering whether to follow suit.

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