The number of patients catching Covid-19 at King George Hospital and Queen’s Hospital spiked in December because on-site tests were not picking up the new variant, it has been revealed.

About a fifth of patients who have tested positive for Covid at the Barking, Havering and Redbridge University Hospitals NHS Trust (BHRUT) hospitals - King George in Barley Lane, Goodmayes and Queen's in Rom Valley Way, Romford - since the start of the pandemic definitely or probably caught it in hospital.

In November, the trust reported nine Covid outbreaks since the start of the pandemic. A report prepared for a board meeting on Tuesday, February 9 showed there have been 10 more since.

It says that since March, almost 650 patients either definitely or probably caught Covid-19 while in the hospitals, meaning they tested positive eight or more days after entering hospital.

The trust suggests outbreaks increased sharply after November because on-site Covid tests were “not fully sensitive to the newly identified variant strain”.

During December, the new UK variant of the Covid virus was thought to be responsible for almost two-thirds of infections in London.

On December 23, the trust “urgently stopped in-house testing and sent all Covid tests to outsourced laboratories” as a result.

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It plans to look into how many of its patients who tested negative in hospital later tested positive for the new strain of the virus at a testing facility.

The trust hopes that vaccinating hospital staff will help to reduce the number of outbreaks in the hospital by preventing asymptomatic staff spreading the virus between patients.

The trust’s chief executive Tony Chambers said it aimed to ensure “the overwhelming majority” of staff accepted the vaccine.

He said: “We have used a wide variety of methods to encourage take up including videos and a very well attended virtual webinar, where questions and concerns were raised and answered by our clinical team.”