Does admitting patients suspected of having COVID-19 to hospital increase the spread of the virus? That’s one explanation for why the number of deaths in the Italian region of Veneto is so much lower than in Lombardy. As of Saturday, April 4th, Lombardy had a case fatality rate (CFR) of 17.6%, while Veneto’s CFR was just 5.6%. The population of Lombardy is 10 million and Veneto 4.9 million, but Lombardy had recorded 8,656 Covid deaths by April 4th, while Veneto had recorded 607.
Part of the reason for this discrepancy is that the authorities have done much more testing and contact tracing in Veneto. But another reason may be that far fewer people suspected of having the virus have been admitted to hospital in Veneto. In Lombardy, 65% of patients diagnosed with COVID-19 were admitted to hospital at the start of the outbreak, while in Veneto only 20% of people were. The theory isn’t that people diagnosed with the virus are more likely to die if admitted to hospital, but that the higher percentage of admissions in Lombardy meant non-COVID-19 patients and hospital staff were more likely to be infected and then infect others.
A group of doctors from the Papa Giovanni XXIII hospital in Bergamo wrote a paper for the New England Journal of Medicine setting out this theory last month. “We are learning that hospitals might be the main COVID-19 carriers,” they wrote. “They are rapidly populated by infected patients, facilitating transmission to uninfected patients.”
If this theory is correct, it suggests that the policy of ramping up the NHS’s capacity to treat patients with COVID-19, and admitting more and more of them, may be spreading the infection. If the NHS’s admission criteria for Covid patients changes, and more patients are told to remain in their homes, as the Papa Giovanni XXIII hospital staff are recommending, that could mean relaxing the social distancing measures won’t result in the NHS becoming overwhelmed.
‘At the Epicenter of the Covid-19 Pandemic and Humanitarian Crises in Italy: Changing Perspectives on Preparation and Mitigation‘, Mirco Nacoti, MD, et al, New England Journal of Medicine, March 21st 2020
‘Fewer deaths in Veneto offer clues for fight against virus‘ by Miles Johnson, Financial Times, April 5th 2020
‘Hospitalising coronavirus patients can cause more deaths, Italy data suggests‘ by Nick Squares, The Telegraph, April 6th 2020
‘Ground Zero: When the Cure is Worse than the Disease‘ by Jonathan Tepper, Medium, April 13th 2020