Coronastream April 2022: second anniversary edition

Posted on May 6, 2022   by Dr. Tim Inglis

In this special blog series, medical microbiologists led by Dr Tim Inglis summarise some of the research that will be essential to inform COVID-19 countermeasures. Find out more about the project in Dr Inglis' Editorial 'Logic in the time of coronavirus', published in theJournal of Medical Microbiology


Are we nearly there yet? 

It’s now over two years since we started on this pandemic journey. You can hear the children in the back of the car piping up before we’re due for the next pitstop. At least, it feels that way after local data suggests we have passed the peak of our latest surge. But noting that we’ve managed to get away with a very flat epidemic curve, the tail end looks set to wag for weeks to come. The tenacity of the Omicron variant of SARS-CoV-2 and its recombinant progeny has frustrated everyone to the point of exhaustion. Whether it’s compassion failure, COVID fatigue or a longing for normality; people have started to drop their guard to the point where test participation rates fall every weekend. With that has come the rise of the vocal anti-vax, anti-mask, anti-restriction lobby. Mandates are in their crosswires. So, this month we’ll look at vaccine and mask mandates, through the eye of the published, peer-reviewed literature. Regrettably, we are still not free from the grip of COVID globally. But in some places, we’re on a roll, even if it may seem more like a dry cracker. 

CONGRUENCE. Long COVID; musculoskeletal complications 

Comelli A, et al. Patient-Reported Symptoms and Sequelae 12 Months After COVID-19 in Hospitalized Adults: A Multicenter Long-Term Follow-Up Study. Front Med (Lausanne). 2022 Mar 22;9:834354. doi: 10.3389/fmed.2022.834354. 

In this prospective, multicentre observational study of long-term consequences of COVID in Italian patients, over 19% required hospital readmission or emergency department access in the year after their initial hospital discharge. Most respondents experienced exertional dyspnoea and fatigue, and almost a third had gastrointestinal symptoms. These were more common in females and people with co-morbidities, the most common of which were cardiovascular diseases. 92% of respondents reported at least one persisting symptom. Almost half the study population was unreachable or refused to participate. Interestingly, this group had an older median age, were more often discharged to rehabilitation or nursing homes and had a higher number of comorbidities. 

Gavrilova N, et al. New Clinical Phenotype of the Post-Covid Syndrome: Fibromyalgia and Joint Hypermobility Condition. Pathophysiology. 2022 Jan 19;29(1):24-29. doi: 10.3390/pathophysiology29010003. 

This collection of case reports focuses on muscular and joint pain formally diagnosed as fibromyalgia and joint hypermobility. These appear to be associated with autonomic disorders and polyneuropathy and an increase in C-reactive protein and antinuclear antibodies. The authors note that this may be part of a disease spectrum including hypermobile Ehlers-Danlos syndrome and fibromyalgia. They suggest a clinical case definition of fibromyalgia syndrome with hypermobility developing after COVID-19, and raise the possibility that COVID-19 acts as a trigger for immune reactions to connective tissue proteins that lead to fibromyalgia. 

CONSISTENCY. The epidemiology of attitudes to COVID and its control 

Opposition to voluntary and mandated COVID-19 vaccination as a dynamic process: Evidence and policy implications of changing beliefs. 

In this study of attitudes to vaccination through the life of the pandemic, Schmelz and Bowles questioned a panel of people in a series of surveys to gauge the consistency of their beliefs about COVID vaccination. Their findings expose a fascinating ebb and flow of vaccine opposition, leaving only a tiny proportion (3.3%) consistently opposed to vaccination. However, there was a consistently larger level of opposition to vaccination at the time of each survey. These results suggest that people change their minds about whether the COVID vaccine is the right choice for them. Interestingly, the figures also suggest that mandates may have increased some people’s opposition to vaccination. The discussion opens up themes of public health policy, direction and communication around the need and urgency of COVID vaccination.  We have to be cautious about extrapolating these findings from an adult German population to other groups and regions, but if replicated elsewhere they provide useful insight into the shifting sands of public opinion on the contested issue of mandatory vaccinations. 

Predictors of adherence to public health behaviours for fighting COVID-19 derived from longitudinal data.

In this international survey of subjective perception of COVID-19, the authors found that personal risk perception predicted personal hygiene behaviour, while at a social level, social norms predicted social distancing behaviour. Confidence in government and cultural tightness predicted support for behaviour mandates, but clarity of communication predicted support for protests against lockdown. This adds weight to the argument that more effort needs to be devoted to the frequency, quality and consistency of public health communication during a pandemic emergency, particularly in populations with a high level of individualism. 


Does SARS-CoV-2 affect neurodegenerative disorders? TLR2, a potential receptor for SARS-CoV-2 in the CNS.

This review article highlights the potential interactions between SARS-CoV-2 and both Alzheimer’s and Parkinson’s Disease (AD and PD). A substantial proportion of people with COVID suffer from neurological symptoms, most commonly headache and fatigue, despite the relative paucity of ACE2 receptors in the nervous system. The authors propose Toll-like Receptor 2 (TLR2) as a plausible alternative receptor for SARS-CoV-2. They also note that patients with dementia have an increased risk of SARS-CoV-2 infection and those with the infection can have clinical features of common neurodegenerative diseases. As AD and PD are the most common neurodegenerative disorders, the interaction between them and COVID comes under scrutiny in this review. Central nervous system entry of SARS-CoV-2 was originally considered to occur via the olfactory bulb, but other routes have since been proposed: via the corneal epithelium, across the blood brain barrier, via the choroid plexus or by axonal transfer from the peripheral nervous system. They draw attention to the 2-3 times higher risk of SARS-CoV-2 infection in patients with dementia, and note that the infection may exacerbate AD neuropathology. SARS-CoV-2 may also trigger features of PD in healthy individuals. They postulate that persistent viral infection in the central nervous system may result in chronic inflammation and consequent neurodegenerative pathology. 

CURTAILMENT. NPIs, vaccines, drugs 

Modeling COVID-19 Mortality Across 44 Countries: Face Covering May Reduce Deaths.

The proposition that mask-wearing contributes to a reduction in mortality was tested in a retrospective study of 44 countries including countries with and without mask mandates. Average COVID-19 mortality was over five times higher in countries without mask policies, and the average daily increase was also higher. This is further evidence in favour of mask-wearing as a means of preventing excess deaths. 

Drug Prescriptions in the Outpatient Management of COVID-19: Evidence-Based Recommendations Versus Real Practice.

This prescribing study from Italy shows changes in prescribing patterns over the course of the pandemic. Azithromycin and hydroxychloroquine both featured as common outpatient treatment choices despite a lack of evidence for beneficial effect. Corticosteroids, on the other hand, came into common use after more formal recommendation. In some months, more than 30% of patients received one or more of the treatments identified in the survey. The authors conclude with a comment about regulatory bodies possibly finding new ways to respond to an emergency. 

Additional online resources