Reports this week that up to 20% of hospital inpatients in England acquired covid-19 while in hospital for other reasons, comes as no surprise. Those of us working in hospitals have seen many cases of patients being infected while in hospital. In some, it is difficult to be certain where a patient acquired covid, but it seems highly likely in patients who were in hospital for other reasons, and where the incubation time allows no alternative explanation, that they acquired the virus while in hospital. 

What makes it worse is that these patients often spend time on “clean” wards risking further spread to other patients and healthcare workers. The figures published over the weekend, give some insight into how widespread nosocomial infection is for covid. But, nevertheless we need formal figures and a greater understanding of how often covid-19 is acquired in healthcare settings by healthcare workers and patients—and the currently very rare visitor. This is essential so that hospitals remain trusted as a place of healing, rather than a place of infection and unintentional harm.

So far, in the UK, the focus has largely been on the lack of adequate personal protective equipment and the infection risk that covid-19 poses to health and social care workers. However, the recent report suggests that healthcare workers are contracting covid in the community or through work. If they are asymptomatic and not tested, they risk infecting covid negative patients, as well as their colleagues. 

Having coloured zones (currently Red, Green, and Amber) can help, but does not protect against those developing symptoms and/or a positive test result when on a “clean” ward after being clinically/test negative on admission. There will be the inevitable situations where patients who appear clinically negative are exposed to positive patients on amber wards. Clinical reality will not neatly match a colour.

Widespread testing, contact tracing, and quarantining is the obvious solution to limiting the spread of nosocomial infections. In the UK, starting track and trace will be a complex and herculean task. The obvious place to start is where most patients with confirmed covid are: hospital and care homes. It is unlikely apps on smartphones will help in hospitals when healthcare workers will so often be near a patient with covid-19. Hospital healthcare workers can’t isolate themselves every time their App says they’ve been near a covid-19 patient, and if well protected with adequate PPE, would not need to. 

There are similar problems in patients. Many, particularly frail older patients, will not have a smartphone, let alone have it with them in hospital. How can we map the complex physical journeys of patients within hospitals—hoping most hospitals have actually got mobile phone reception/WiFi to do that? Our patients and healthcare workers, particularly the vulnerable or those that live with the vulnerable, have the right to know when they have been exposed in “clean” areas. They have difficult decisions to make about self-isolation, sometimes away from their loved ones. The solution to track and trace in healthcare will likely require many human tracers. It is unclear if the tracers promised by the government will be linking in to the hospitals, or just based in the community. Tracers will also be needed to inform those that have been discharged, but came into contact with covid-19 while in hospital. 

Hopefully in hospital transmission of covid is already reduced compared to the beginning of the pandemic. Measures have already been put into place to mitigate the spread of covid in hospitals, for example, the recent start of testing of all new admissions, pre-admission quarantining at home for elective admissions, physical distancing of patients, increased testing of healthcare workers, and reduced turnaround of test results. This will all have an impact. These measures should reduce the mixing of possible, but likely negative, patients with patients who turn out to be PCR positive or clinically highly suspicious. But measures such as physical distancing of patients will come under pressure as lockdown measures ease and hospitals start to fill up with non-covid related patients. 

There are still, of course, many questions about the false negative rates of tests, how much spread occurs via fomites, of pre- and asymptomatic transmission, and how exactly to define hospital acquired covid-19. Do we need to start testing asymptomatic or presymptomatic healthcare workers. If so then how would this be rolled out, who should be tested, and how frequently? The same should possibly apply to any clinically covid-19 negative patient during longer inpatient stays and intrahospital transfers, in particular since these are likely the most vulnerable patients. When and where does deep cleaning need to occur? What lessons can we learn from superspreader events in the community in covid-19 and ones studied in hospital during MERS outbreak, e.g. in Korea. [6] Some of the solutions are likely to focus on patient proximity/single bays and aerosol spread in poorly ventilated areas. 

The hope is that primary care, outpatient clinics, and day hospitals will be safer environments. But we need reliable data so that our patients and healthcare workers can make informed choices. This knowledge will help limit the spread of covid-19 and also prevent future harm as a result of patients being too fearful to attend healthcare in coming years.

There might be some uncomfortable truths in hospital-acquired covid-19, but the first step is to start defining and measuring it. Our patients and healthcare workers deserve it. Only trustworthy data can give people the confidence that physical healthcare is a safe place for them.

Jan Coebergh is clinical lead for neurosciences at Ashford St Peter’s Hospitals, honorary consultant neurologist at Royal Surrey Hospitals and St George’s Hospitals and honorary senior lecturer at St George’s University. He trained in the UK (MBBS Newcastle) and the Netherlands. This article was written in a personal capacity.

Competing interests: None declared.

References:

1. Wang, D; Hu, B.Hu, C.; et al. Clinical Characteristics of 138 Hospitalized Patients With 2019 Novel Coronavirus–Infected Pneumonia in Wuhan, China. JAMA. 2020;323(11):1061-1069.
2. Hunter, E., Price, DA., Murphy, E. et al. First experience of COVID-19 screening of health-care workers in England. The Lancet. S0140-6736(20)30970-3.
3. Folgueira, MD., Munoz-Ruiperez, C.,  Alonso-Lopez, MA et al. SARS-CoV-2 infection in Health Care Workers in a large public hospital in Madrid, Spain, during March 2020. Available at: https://www.medrxiv.org/content/10.1101/2020.04.07.20055723v2
4. Heinzerling, A. Stuckey, MJ, Scheuer, T. et al. Transmission of COVID-19 to Health Care Personnel During Exposures to a hospitalized patient. Solano County, California, February 2020. Available at https://stacks.cdc.gov/view/cdc/86726
5. Vincent C. C. Cheng, Shuk-Ching Wong, Jonathan H. K. Chen. Escalating infection control response to the rapidly evolving epidemiology of the coronavirus disease 2019 (COVID-19) due to SARS-CoV-2 in Hong Kong. Infection Control & Hospital Epidemiology. Volume 41, May 2020 , pp. 493-498.
6. Chun, BC. Understanding and Modeling the Super-spreading Events of the Middle East Respiratory Syndrome Outbreak in Korea. Infect Chemother. 2016 Jun; 48(2): 147–149.