Alex Nowbar reviews the latest research from the top medical journals.
Annals of Internal Medicine
The horrors of Italy’s experience with covid-19 readied us for the supply-demand mismatch for ventilators (by which I mean not only the machine but the bed, trained staff and non-trivial amount of resources required to care for a intubated covid-19 patient). It was clear that not everyone needing higher levels of respiratory support would be offered it (which, lest we forget, was also true before covid-19, albeit with huge regional variation). Ethics expert, Antommaria et al’s survey looked at US “triage” policies in 67 hospitals because triage sounds better than rationing, doesn’t it? Ok, only half of those hospitals had policies and some directors were not able to share the policies with the researchers. Most policies used scoring systems, presumably for the semblance of objectivity. The most frequently cited triage criteria were need, age, conservation of resources and lottery. Those last two mean denying a ventilator to those who would need a disproportionate amount of resources and allocating resources by choice rather than first-come first served when survival chances with a ventilator are unclear respectively. These options aren’t exactly palatable but there are worse ways of choosing who gets a ventilator when supply is short.
Spinato et al surveyed mildly symptomatic outpatients with SARS-CoV-2 in Italy to estimate the prevalence of an altered sense of taste or smell. In people who had tested positive and responded to the survey, 64.4% had some degree of altered sense of taste or smell. The timing of the onset of this symptom was variable: in 18% it came before the onset of other symptoms, in 35% it occurred with other symptoms, in 42% it came after the onset of other symptoms and in the rest it was their only symptom. One limitation of the study was that it was based on questioning the patient about their symptoms rather than objective measures so there is a chance that symptom prevalence and/or severity could have been overestimated. However, the methods were pragmatic given the circumstances. This is definitely a symptom worth watching out, for although this type of study doesn’t tell us how specific a symptom this is for covid-19.
Privacy violations with IT system for tracing in South Korea
The Korea Centers for Disease Control and Prevention was permitted to collect, profile, and share data that in the UK I like to think we’d never dream of sharing including location data from mobile carriers, CCTV from the police, card transactions from credit card companies, public transport records and prescription and medical records. Some would argue that this is justified in view of the pandemic. Others would argue it violates the human right to privacy and that instead, governments must find another solution. According to Park et al’s letter, public identification of businesses visited by infected people led to loss of business and ages, sex and nationalities of infected people were published on the Ministry of Health website. It went beyond the minimum necessary to achieve tracking goals. Park et al present strategies for a more balanced approach i.e. disclosure of less granular data. There are some relevant lessons here for other countries as tracking gains traction as a possible lockdown exit strategy.
Not a good time to be immunosuppressed
Yes, that’s an understatement. Akalin et al’s letter describes the outcomes of 36 kidney transplant recipients with COVID-19 in Montefiore Medical Center in New York. 10 died, 28 were hospitalised and 11 received mechanical ventilation (of those who died 7 had had ventilation). 24 of the 28 who were admitted to hospital had their antimetabolite medication withdrawn. Tacrolimus was withheld in 6 of the transplant recipients. These patients had low CD3, CD4 and CD8 counts at presentation suggesting that reducing immunosuppression could be sensible but noone really knows what to do with these medications in this context. The key message from this cohort is that kidney transplant recipients have an alarmingly high mortality rate. Thus they should (continue to) aggressively shield themselves.
Nor a good time to be in a care home
Arons et al found that the virus spread like wildfire – 64% of residents had tested positive 23 days after the first resident tested positive. More than half of those who tested positive had no symptoms at the time of testing. This data is invaluable in comprehensively documenting how a facility can be so rapidly decimated by the virus so lessons can be learned. The most interesting analysis in this study is of viral load/shedding by symptom classification: pre-symptomatic, typical symptoms, atypical symptoms and (remained) asymptomatic. Pre-symptomatic patients could be retrospectively identified because everyone was tested and followed up to see who developed symptoms. Viral loads were similar between groups. The key lesson is the need for mass testing especially in care homes regardless of symptom status. The transmissibility of the virus without symptoms also supports the idea of mask use for the general public.
Alex Nowbar is a clinical research fellow at Imperial College London
Competing interests: None declared