The Friday Report – Issue 24 Covid-arg.com
By Matthew Fletcher, Nicola Oliver and John Roberts
COVID-19 Actuaries Response Group – Learn. Share. Educate. Influence.
COVID-19 is still one of the hottest topics for scientific papers and articles. The COVID‑19 Actuaries Response Group will provide you with a regular Friday update with a curated list of the key papers and articles that we’ve looked at recently.
Improving Test, Trace & Isolate Effectiveness
We recently reported on a study that suggested high non-compliance with self-isolation and quarantine measures. With this in mind, a paper (link) published by the Centre for Mathematical Modelling of Infectious Diseases has investigated alternatives to the current 14-day quarantine period which may be more acceptable to those asked to comply, together with improvements to the test and trace system which may increase its effectiveness.
The paper notes that release from isolation after Day 10 given a negative test would be as effective as waiting until Day 14 without testing. In addition, testing everyone traced immediately would reduce transmission by over 50%.
The study notes that halving observed delays from the current four days in making a contact would reduce the pre-tracing transmission potential from 29% to 11%. Along with improving the low adherence level, which it puts at 10%, these two factors have the greatest potential to improve the effectiveness of the system.
Effect of school closures on mortality from COVID-19
This paper (link) aims to replicate and analyse the information available to policymakers in March 2020, using the CovidSim code which implements the Imperial model applied to the epidemic.
The paper confirms the finding that the interventions put in place in March would be very effective in reducing peak demand for ICU beds but notes that they would also prolong the epidemic, with school closures and isolation of young individuals in particular increasing the overall number of expected deaths but delaying them until second or subsequent waves.
This paper was produced by specialists in physics and computer simulation rather than specialists in infectious disease; however this is perhaps to be expected given that its aim is to replicate the CovidSim code rather than to produce novel analysis of the pandemic.
Clinical and Medical News
Remdesivir is an anti-viral drug that has previously demonstrated effectiveness in treating Ebola virus. Anti-viral drugs are not able to kill a virus in the same way that an antibiotic does; antivirals work by slowing the rate at which the virus is replicated by the hosts cells, thus giving the immune system more time to tackle the pathogen (link).
Remdesivir has been under investigation for its effectiveness against the SARS-CoV-2 virus, and this analysis reports promising results. This double-blind, randomized, placebo-controlled trial (the gold-standard), found that a 10-day course of remdesivir was superior to placebo in the treatment of hospitalized patients with COVID-19. Recovery time was reduced – median, 10 days vs. 15 days.
Treatment with remdesivir may also have prevented the progression to more severe respiratory disease; in addition, all-cause mortality was 11.4% with remdesivir and 15.2% with placebo (hazard ratio, 0.73; associated 95% confidence interval, 0.52 to 1.03).
Coronavirus cross immunity
The range of COVID-19 disease severity symptoms is driven by a number of factors; not least the potential that some individuals may have some kind of pre-existing protective immunity. It has been suggested that previous exposure to the common cold (itself a coronavirus), may elicit a T-cell response providing protection for subsequent exposure to SARS-CoV-2. This study suggests that this may indeed be the case, and that this could explain the range of mild, self-limiting disease to acute respiratory distress syndrome and death.
Neurologic manifestations and associated morbidity in COVID-19
It is now established that SARS-CoV-2 causes multi-organ disease (link), not just limited to the respiratory system. This includes involvement of the central and peripheral nervous system. This study examined the neurologic manifestations, their risk factors, and associated outcomes in 509 patients admitted with confirmed COVID-19 within a hospital network in Chicago, Illinois (these being the first COVID-19 patients in the first month of the pandemic).
Neurologic manifestations were present at COVID-19 onset in 215 (42%), at hospitalization in 319 (63%), and at any time during the disease course in 419 patients (82%).
Manifestations included myalgia, headache, encephalopathy, dizziness, dysgeusia (loss of taste), and anosmia (loss of smell).
This study adds to the increasing and concerning body of literature on the potential morbidity burden from COVID-19, ‘long COVID’, as highlighted in our previous bulletin.
Children and adolescents can serve as the source for COVID-19 outbreaks within families
The US Centers for Disease Control and Prevention (CDC) produce weekly morbidity and mortality reports in general, and COVID-19 related. The latest release reports on an outbreak that occurred during a 3-week family gathering of five households in which an adolescent aged 13 years was the index and suspected primary patient; 11 subsequent cases occurred.
The following graphic shows the COVID-19 cases among children, adolescents, and adults within the outbreak.
This outbreak highlights several important issues:
- Children and adolescents can serve as the source for COVID-19 outbreaks within families, even when their symptoms are mild.
- This investigation provides evidence of the benefit of physical distancing as a mitigation strategy to prevent SARS-CoV-2 transmission. None of the six family members who maintained outdoor physical distance without face masks during two visits to the family gathering developed symptoms.
- Rapid antigen tests generally have lower sensitivity (84% – 98%) compared with RT-PCR testing.
- Regardless of negative test results, persons should self-quarantine for 14 days after known exposure or after travel.
- SARS-CoV-2 can spread efficiently during gatherings, especially with prolonged, close contact.
Point-of-care (POC) testing
In our previous monthly review of medical developments, we highlighted the potential benefits of POC testing. Rapid turnaround of results can improve patient flow through clinical areas and expedite initiation of appropriate treatments.
The clinical impact of molecular point-of-care testing for COVID-19 is reported in this study. The trial took place during the first wave of the pandemic in the UK, from March 20 to April 29, 2020. Around 500 patients were recruited from the acute medical unit, emergency department, or other acute areas of Southampton General Hospital, UK.
The researchers report that routine use of point-of-care testing for emergency admissions was associated with a large reduction in time to results and improvements in infection control measures, patient flow, and recruitment into other clinical trials, compared with laboratory PCR testing.
Furthermore, the diagnostic accuracy of the QIAstat-Dx Respiratory SARS-CoV-2 Panel, the type of POC test used in the study, was high compared with the composite PCR reference standard.
The relationship between ethnic background and severe COVID-19
People of minority ethnic backgrounds are disproportionately affected by severe COVID-19; the drivers are not clear, but will include the presence of co-morbidities and socioeconomic deprivation.
In this study, researchers sought to examine whether ethnic background affects the risk of hospital admission with severe COVID-19 and/or in-hospital mortality. This observational cohort study conducted at King’s College Hospital Foundation Trust (KCHFT) in London examined consecutive adult patients (age ≥18 years) requiring emergency hospital admission with a primary diagnosis of COVID-19, between 1 March and 2 June 2020.
Local contextual population demography, individual-level comorbidity burden and socioeconomic deprivation were taken into account.
This study reports a strong association between Black or Mixed ethnicity (but not Asian ethnicity) and an increased risk of admission for COVID-19, which was only partly attenuated after adjustment for comorbidities and socioeconomic deprivation.
Vaccine Roll Out
For those hoping that an effective vaccine will be available quickly, a report (link) from the Royal Society’s Delve Initiative may make sobering reading. The very comprehensive analysis of all the steps needed to immunise the world’s population goes beyond the usual discussion around how soon can we find a vaccine that works. As an example, it suggests that 8,000 separate 747 movements would be needed to get the vaccine to everywhere needed.
It sets out a likely priority order for vaccination in the UK, and also notes that particular attention may be required for some groups (eg ethnic minorities) to ensure that uptake is at the required levels.
PHE Surveillance Report
The weekly COVID-19 Surveillance Report (link) has a new look and feel this week, as this is the time of year when the PHE would normally start issuing its Flu Reports. So we now have a combined report covering both infections.
The messaging is, unfortunately, very familiar, with steep increases in infection levels being reported – particularly across the North of England, as shown in the following graphs. Another noticeable feature of the data is that infectivity amongst the 10-19 age group has jumped up. Whether these are concentrated in the 18-19 age group (first year university students) is not split out, although given press reports of halls of residence being hotspots, it seems likely.
ONS Surveillance Report
The ONS weekly report uses random sampling, and thus might be regarded as a better guide to infectivity levels. It shows a similar picture to the PHE report, with a sharp increase in the 7 days to 1 October. Levels of infectivity have jumped to 1 in 224 (1 in 500 last week), with 224,000 (116,000 last week) estimated to be infected in total. New infections have more than doubled to 17,400 (8,400 last week) per day.
The same patterns of regional and age infectivity are seen, with stronger evidence of universities being a key contributor, as it groups by ages 12 to 24.
The latest SAGE estimate of R is 1.2 to 1.5, down from 1.3 to 1.6 last week. Despite the significant restrictions that have been in place in the North now for some weeks, there is no obvious differential in terms of R being lower there, although conversely, two areas which continue to have low infectivity, the East and South West, are at the higher end of the estimates this week.
ONS: Flu v COVID
The ONS has sought to dispel the myth that COVID is no more deadly than flu, with another of its excellent summaries (link). It starts by making clear the distinction between “from COVID” and “with COVID”, and uses the former measure throughout the paper. It notes that over three times as many people have died from COVID than flu and pneumonia combined this year.
The paper also goes on to look at historic trends of annual deaths from flu and pneumonia and comes to the same conclusion, that COVID is much more deadly than either of them. One common effect of COVID is indeed pneumonia, but the distinction made at the start to count only those cases where COVID was the primary cause makes it clear that COVID caused the secondary condition.
And finally … (NSFW!?)
‘She was supposed to cure the coronavirus … instead, she fell in love with it.’
Short of reading material this weekend? Bag your copy of ‘Kissing the CoronaVirus’… (not to be advised, i.e. kissing the virus, a sure way to increase transmission) – kissing viruses
The author, M.J. Edwards apparently bears no relation to our collaborator M.F.J. Edwards … (but a similar writing style perhaps?)
9 October 2020