COVID-19 Shielding Less Effective Than Hoped

Protecting those most at risk from Covid-19 during the first wave of the pandemic may not have been as effective in protecting against infection and death as hoped, according to a new study.

The study – led by the University of Glasgow and published in Scientific Reports – found that between March and May 2020, patients advised to shield in NHS Greater Glasgow and Clyde (NHSGGC) had a higher infection and death rate than patients who were not advised to shield themselves.

Many Western countries, including Scotland, have used shielding (extensive self-isolation) of people believed to be at high risk for COVID-19 to protect them and reduce the demand for healthcare.

The study looked at data from more than 1.3 million patients registered with GP practices in NHSGGC. Of this group, 27,747 individuals were advised to shield (self-isolation for an extended period of time) and a further 353,085 were not advised to shield but were categorized by the researchers as at moderate risk of Covid-19 due to their health conditions such as diabetes.

The authors found that, compared with low-risk individuals (the other 934,239 people in the study), people who were advised to shield were eight times more likely to have confirmed infections.

Those advised to protect themselves were also five times more likely to die after a confirmed infection, while those at moderate risk were four times more likely to have confirmed infections than the low-risk group, and five times more likely. to die after a confirmed infection.

In the shielded group, there were 299 (1.1%) confirmed infections and 140 (0.51%) deaths from Covid-19. In the moderate risk group, there were 1,859 (0.53%) confirmed infections and 803 (0.23%) deaths; and in the low-risk group, there were 1,190 (0.13% confirmed infections) and 84 (0.01%) deaths from Covid-19.

The study also found that age 70 and older was responsible for 49.55% of deaths.

Professor Jill Pell, director of the University of Glasgow’s Institute of Health and Wellbeing, said: “Our study highlights that to effectively protect high-risk individuals, shielding should be used in addition to other population-wide measures such as physical distancing, face covering and hand protection. hygiene.

“Our study also showed that foreclosure may be of limited value in reducing the burden on health services because, despite the foreclosure strategy, high-risk individuals had an increased risk of death. We believe that, as a population strategy to be effective, the screening criteria should have been expanded extensively to include other criteria, such as the elderly.”

The study linked GP, prescribing, laboratory, hospital and death data and compared COVID-19 outcomes between shielded and unscreened individuals in the west of Scotland.

Reference: “Comparison of COVID-19 Outcomes Between Shielded and Unscreened Populations” by Bhautesh D. Jani, Frederick K. Ho, David J. Lowe, Jamie P. Traynor, Sean P. MacBride-Stewart, Patrick B. Mark , Frances S. Mair and Jill P. Pell, July 27, 2021, Scientific Reports.
DOI: 10.1038/s41598-021-94630-6