Covid-19: 167,000 people may have caught Covid in hospital during England's second wave study suggests

Upto 167,000 people may have contracted Covid-19 in hospitals in England between June 2020 and March 2021, during England’s second wave of the pandemic, a new study suggests.

Researchers who assessed Covid-19 infections between June 2020 and March 2021 said their findings show how many cases began in hospitals, revealing the scale of hospital transmissions and highlight contributing factors, including a limited number of single rooms. They also indicated hospitals needed to be better equipped to limit the transmission of future viruses.

Hospital transmission of Covid-19 puts vulnerable people at risk, affects healthcare workers and potentially drives transmission in the community. But despite the obvious risks, there has been little work to assess the extent of hospital transmissions.

Ben Cooper, from the University of Oxford, and colleagues tried to address this knowledge gap by assessing data from 145 English NHS acute hospital trusts, including 356 hospitals with a combined bed capacity of approximately 100,000. Their data included incidence of Covid infection, staff absences due to the virus and classification of the likely source of infection.

Prof Cooper, said: “This study represents the first data-driven attempt to understand the drivers of Sars-CoV-2 transmission in hospitals at a national level and informed efforts to control the hospital spread of Sars-CoV-2 at the time.

“The findings also point to ways we might be able to reduce hospital-based transmission in future outbreaks of other pathogens.”

Between 10 June 2020 and 17 February 2021, a total of 16,950 and 19,355 Covid infections in hospital patients were classified as having either definite or probable healthcare-associated infections respectively.

However, the researchers calculated the data only captures around 26% of such infections (for example, many patients may be discharged before testing positive).

Researchers combined reported infection numbers with estimates of the proportion of infections and suggested the number of hospital-acquired infections range from 95,000 to 167,000. This means that 1% to 2% of all hospital admissions led to an infection. According to the findings, there was considerable variation in the rate of hospital-association infections and the study indicates the highest rates were seen in the north-west regions of England, and the lowest in the south-west and London regions.

They suggested low availability of single rooms and reduced heating of hospital buildings could play a part in increased infections.

The vaccination of healthcare workers was associated with lower infection rates, the study also found.

The authors say considering these findings could inform measures to reduce hospital transmissions, which could protect vulnerable patients and healthcare workers as well as reduce community transmission.

The researchers say: “These findings reveal the previously unrecognised scale of hospital transmission, have direct implications for targeting of hospital control measures and highlight the need to design hospitals better equipped to limit the transmission of future high-consequence pathogens.”

An NHS spokesperson said: “While hospital infections inevitably rose over the peak of the pandemic’s second wave, the ONS and other data have conclusively demonstrated that the root cause of rising infection rates in hospitals was the rising rates in the community. NHS staff followed UKHSA Covid-19 infection prevention control guidance as cases increased to keep patients and staff as safe as possible.”