key: cord-0894856-r3lk08d0
authors: McLennan, Amy K; Hansen, Anne Katrine Kleberg; Ulijaszek, Stanley J
title: Health and medicine cannot solve COVID-19
date: 2020-08-27
journal: Lancet
DOI: 10.1016/s0140-6736(20)31796-7
sha: 392e29c7adcb04ba79de311f9bbc79ddad22cf77
doc_id: 894856
cord_uid: r3lk08d0

nan

. Over the next 2 weeks, the patient's rash gradually improved. 6 weeks later, serology tests against anti-SARS-CoV-2 antibodies (Elecsys Anti-SARS-CoV-2, Roche Diagnostics, Rotkreuz, Switzerland) were negative. However, PCR testing of the skin using established methods 1 detected SARS-CoV-2 at low copy numbers (37 per 1 × 10⁶ human RPPH1 copies). This case is important because it highlights the shortcomings of currently available testing methods for SARS-CoV-2 infection. Although the sensitivity and specificity of currently available PCR and serology tests are high, swab samples that are taken incorrectly are known drivers of the relatively large number of false negative tests for SARS-CoV-2. 4 Our finding that the patient's serology remained negative is compatible with the hypothesis that some patients with COVID-19 might not establish humoral immunity; an observation that has also been made for other coronaviruses. 5 In summary, this case emphasises the use of SARS-CoV-2 PCR testing of skin biopsy samples as an additional diagnostic tool, helping to shed light on the actual prevalence of COVID-19 in the general population. Additionally, further studies are needed to understand to what extent and at what point during their dis ease course patients with COVID-19 actually develop immunity-a ques tion of uttermost importance, espe cially with regards to the currently ongoing efforts to develop a vaccine to technology, environ ment, education, policing, engi neering, transport, food systems, communication, and more all inter sect as complex expert systems. 2 Any intervention continually shapes, and is shaped by, other parts of these sys tems. For example, lockdown-related transport disruption is impeding routine vaccination programmes, 3 reshaping education, and improving air quality. 4 At the same time, health improvements could come from fields well outside of health. An example of this from London's recent past is the radical reengineering of city landscapes and construction of sewer systems, which substantially reduced infectious disease burden.

Collective interventions will create the new normal that we will inhabit in the future. 5 Yet, the pandemic is framed primarily as a global health crisis, and so the public expects health interventions-a vaccine, new public health measures and hygiene behaviours, and effective treatmentsto end COVID-19 and permit a return to the old normal. We caution against this framing. Medicine is well placed to change the narrative and make space for joined-up thinking about a different future with or without COVID-19.

We declare no competing interests. 

Richard Horton argues that combination prevention and global health collaboration are required to address the COVID-19 pandemic. 1 We agree and suggest this should incorporate further measures. Thinking closely in terms of medical solutions could create false public expectations of a return to normal, and risks closing out non-health interventions that could lead to substantial improvements. COVID-19 has exposed the com plex and interdependent systems of everyday life. Health, politics, economics, Mike Kemp/Getty Images such as radial strength. Accordingly, predilatation was done in 325 (88%) of 372 patients treated with ACURATE neo versus 83 (23%) of 367 patients with SAPIEN 3 (p<0·0001). 1 We compared the frequency of moderate or severe aortic regurgitation stratified by predilatation status and valve type appendix. Although there was no significant difference in the occurrence of moderate or severe aortic regurgitation within treatment groups, the interaction between predilatation status and valve type was highly significant (p<0·0001). However, the effect of predilatation needs to be interpreted in the context of calcification of the native aortic valve complex and differences in device characteristics. Severe calcification has been associated with an increased risk of paravalvular regurgitation. 2 Predilatation is done with the objective to aid device positioning in a heavily calcified landing zone and to improve the expansion of self-expanding transcatheter heart valves. The association of predilatation and paravalvular regurgitation is therefore likely to be confounded by the degree of aortic landing zone calcification.

Although differences in predila tation requirements preclude mean ingful inferences on the effect of predilatation on the risk of paravalvular aortic regurgitation in the SCOPE I trial, the effect of predilatation on clinical outcome has been investigated in dedicated studies. [3] [4] [5] In the DIRECT trial, 3 171 patients treated with selfexpanding devices were randomly allocated to predilatation versus no predilatation. No trend favoured one strategy over the other. Similarly, in the NEOPRO registry, 4 which included 1263 patients, rates of moderate to severe paravalvular regurgitation at 30 days were similar, irrespective of whether patients had predilatation before the implantation of an ACURATE neo valve (5·5% vs 3·4%;

We thank Liang Yao and colleagues for their interest in our Article. 1 They hypothesise that the higher incidence of paravalvular regurgitation in patients treated with the self-expanding ACURATE neo compared with the balloon-expandable SAPIEN 3 valve might have been related to differences in incidence of predilatation rather than to differences in device characteristics.

In the SCOPE I trial protocol, predilatation was mandatory in the ACURATE neo group but optional in patients assigned to the SAPIEN 3 group. 1 This difference is in line with the instructions for use of the two devices, the different implantation methods, and differences in device properties, See Online for appendix

In conclusion, the potential effect of predilatation is an important issue that needs to be taken into consideration. Controlling for this potential confounder could help to minimise the bias of interpreting the findings in different TAVR systems.

Safety and efficacy of a self-expanding versus a balloonexpandable bioprosthesis for transcatheter aortic valve replacement in patients with symptomatic severe aortic stenosis: a randomised non-inferiority trial

Pre-dilatation versus no pre-dilatation for implantation of a self-expanding valve in all comers undergoing TAVR: the DIRECT trial

Impact of direct transcatheter aortic valve replacement without balloon aortic valvuloplasty on procedural and clinical outcomes: insights from the FRANCE TAVI registry

We declare no competing interests. 

Jonas Lanz and colleagues 1 compared the effect of a self-expanding valve with a balloon-expandable valve for transcatheter aortic valve replacement (TAVR) in patients with symptomatic severe aortic stenosis. According to the results, the incidence of paravalvular leakage was higher in the group of patients using the self-expanding ACURATE neo device than in the group of patients using the balloonexpandable SAPIEN 3 prosthesis. However, we are concerned that this finding might be at least partly caused by differences in predilatation between the groups.The necessity of dilatation before the TAVR procedure has been debated in recent years. In the randomised trial by Lanz and colleagues, 1 predilatation was mandatory only for the ACURATE group. However, this requirement might be unnecessary, and an important source of potential bias; for example, in the DIRECT trial, 2 no benefit was found for predilatation among patients with a self-expanding valve. There is controversial evidence regarding the effect of predilatation on paravalvular leak and other clinical outcomes. 2, 3 In one prospective study, predilatation was associated with an increased risk of aortic regurgitation. 3 Because the proportion of predilatation was substantially higher in the ACURATE neo group than in the SAPIEN 3 group (88% vs 23%), 1 it is not certain to what extent the lower risk of moderate or severe aortic regurgitation in the ACURATE group can be explained by the net effect of ACURATE neo versus SAPIEN 3. Latour B. Where to land after the pandemic? A paper and now a platform. 2020. https://www.bruno-latour.fr/node/852.html (accessed June 7, 2020).