Coronavirus swabs and other key NHS tests are under threat after a supply chain failure at a major diagnostics company.
Swiss pharmaceutical firm Roche said problems during a move to a new warehouse had caused a “very significant drop” in its processing capacity.
A spokesperson said Covid-19 tests would be prioritised.
One NHS trust has already advised its GPs to stop all non-urgent blood tests.
In a statement, Roche said: “We deeply regret that there has been a delay in the dispatch of some products.
“We are prioritising the dispatch of Covid-19 PCR [diagnostic] and antibody tests and doing everything we can to ensure there is no impact on the supply of these to the NHS.”
The company is one of two main suppliers of diagnostic testing equipment and materials in England.
The affected warehouse is Roche’s only distribution centre in the UK and covers the whole country.
Dr Tom Lewis, lead clinician for pathology at North Devon District Hospital said his hospital’s trust had sent out communications that all non-urgent bloods in the community should be stopped.
Without rationing these non-urgent tests, he said, they would run out of swabs in “three to four days”.
Even with rationing, essential equipment could run short by next week, he said.
Roche said it could take more than a fortnight to resolve the issue.
Dr Lewis said perhaps most concerning was the shortage of electrolyte tests supplied by Roche since these were “the key test for critically ill patients” as well as being extremely commonly used by GPs to check people’s medications were safe and not damaging their kidneys.
One virologist in the Midlands tweeted that her service had not received Hepatitis C testing kits, and was now running short.
Materials used in cancer diagnostics could also be affected.
In a letter sent to NHS trusts, seen by the BBC, Roche said: “In September we moved from our old warehouse to a new automated warehouse capable of much higher volumes.
“However, during the transition we encountered some unforeseen issues and a very significant drop in our processing capacity. Since then we have worked around the clock to prioritise and manage orders as well as increase this capacity”.
The letter went on to advise local NHS services to “activate [their] local contingency plans” and “look to prioritise essential services only”.