Weekly Report: Issue 30
By 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 weekly update with a curated list of the key papers and articles that we’ve looked at recently
Clinical and Medical News
Common cold viruses and SARS-CoV-2
It has been purported that exposure to common cold corona viruses (CCCoV) may provide some cross immunity against SARS-CoV-2, in particular, where CD4+ T cells reactive against SARS-CoV-2 have been found in unexposed individuals.
In this study, the authors counter the theory and report that in their analysis, CCCoV CD4+ T cells display low activity in COVID-19 patients, but that pre-existing memory on human T cell responses against newly encountered pathogens remains poorly understood.
Epidemiology of COVID-19 from the pre-pandemic period
The CDC in the US have published analysis of the pre-pandemic period in order to describe the global spread of SARS-CoV-2 and characteristics of cases and clusters in affected countries from 31 December 2019 to 10 March 2020.
The researchers undertook web-based surveillance starting on 20 January. To identify new cases, they screened the following data sources daily: national ministry of health or other government websites, press releases, press conference transcripts, and social media feeds (i.e., Facebook, Twitter, Instagram), situation reports from national ministries of health and CDC offices in other countries, and media reports. Where possible, sources were cross validated.
Variables examined included:
- Report date
- Illness onset date
- Patient’s age and sex
- Healthcare worker
- Travel history
- Previous exposure to COVID-19
- Links to known clusters
- Exposure setting
The table below displays the total number of countries and locations with confirmed COVID-19 cases by week from 29 December to 10 March.
Cases with travel links to China, Italy, or Iran accounted for almost two-thirds of the first reported COVID-19 cases from affected countries.
Trends in County-Level COVID-19 Incidence in Counties with and without a Mask Mandate
The US CDC publish regular weekly morbidity and mortality reports. In this latest report, they describe the differences in COVID-19 incidence by county in Kansas. An executive order relating to mask wearing was issued by the governor of Kansas effective from 3 July, with authority to opt-out on a county by county basis. CDC finds that the 24 counties that did not opt out of the mask mandate experienced a decrease in COVID-19 incidence, whilst the 81 counties that did opt out experienced an increase in cases.
Sensitivity analyses were conducted and other factors such as other public health measures, and county-related characteristics were accounted for.
Administration of convalescent plasma is undertaken for various diseases, in the hope that it will stimulate the immune system. However, to date it has only demonstrated efficacy in the treatment of Argentine haemorrhagic fever. Naturally, there is a great deal of interest in the potential application of convalescent plasma to treat COVID-19.
In this randomised trial, 228 patients with severe COVID-19 pneumonia were assigned to receive convalescent plasma and 105 to receive placebo. The primary outcome was clinical status 30 days following administration.
This study reports that the clinical outcomes between the two groups were not significantly different at 30 days, neither were there any observed mortality advantages in the intervention group.
Management of Long COVID
The National Institute for Health and Care Excellence (NICE) has begun the process of developing guidelines for the management of the long-term effects of COVID-19. The final date of publication has not been announced, though given the rapid development of other COVID guidelines, this could be within a week or two.
The guideline scope sets out the key themes which will be:
- Investigations and assessment
- Management and rehabilitation
- Lived experience of people
NICE want to include identification of risk factors, prevalence, pharmacological and non-pharmacological interventions, assessment of symptoms and impact on normal activities, potential inequalities, and the lived experience.
The last two weeks have seen announcement of the results of three phase 3 trials for vaccines against SARS-CoV-2. Of particular interest has been that of the AstraZeneca vaccine results due to what appears to be a reported dosing error. No results have been presented in a peer reviewed format for any of the vaccines; we will be publishing a vaccine update in the coming weeks.
ONS Weekly Infectivity Report (link)
The weekly surveillance report was published a day early this week, presumably to tie in with the government announcement as to which areas would be in which tier following the end of the national lockdown next week. The latest data is to 21 November .
In England there are encouraging signs that the restrictions imposed on 5 November are beginning to have an effect, although there is still some variation between the regions. Unfortunately the best measure to identify a possible change, new infections, is not available in the latest report, due to a problem at one of the testing labs. Nevertheless, the plateau we saw last week in overall infectivity has now turned into a small decline, although the infectivity level is still put at 1.10% of the community population as at 21 November, compared with a peak of 1.27% between 9 and 12 November.
Similarly there is more encouraging news from both Wales and Northern Ireland. In the Principality, the effect of the firebreak between 24 October and 8 November can be clearly seen. Infectivity peaked at 1.00% on 30 October, and has now fallen by over 50% to 0.47%. It is of note that this fall has continued beyond the period where we might have expected a levelling following the end of the firebreak, although on Friday it was announced that the R estimate for Wales has risen to 1.4, and further restrictions are to be introduced.
In Northern Ireland tight restrictions were introduced on 16 October, and after a peak on 20 October at 1.33%, the estimated rate has fallen consistently to stand at 0.62%. The province has just finished a week with some respite, before commencing a further toughening of measures, though we won’t see any effect of this for a couple of weeks.
In contrast, north of the border, there is evidence that infectivity levels are still increasing, albeit slowly, with the latest estimate for Scotland put at 0.92%. This follows a period when it appeared as though levels were stabilising, and is probably behind the recent decision by the Scottish Government to move some of the key Central Belt areas to the highest tier.
Infectivity Estimates for Scotland and Northern Ireland
ONS Antibody Survey (link)
Every month we also get an update from the ONS on levels of antibodies seen within the community. During the summer there was a gradual decline, as antibody levels from the first wave started to decline. Intuitively, we might expect to see this reverse as the second wave has accelerated, and indeed that is the case.
Overall, 1 in 15 of the English population are observed to have antibodies, being 6.9% of the population over age 16 (3.1m people). Of interest, whilst the north has been more badly affected this time, the regional variation still shows London as having the highest prevalence.
ONS Excess Winter Deaths Report (link)
Making it a hat-trick this week, the ONS published its annual analysis of excess winter deaths. This normally looks at the four-month periods immediately before and after the winter months (Dec – Mar), but has had to be adjusted this year given the four months following winter were of course distorted by COVID deaths. It therefore has published “with COVID” and “without COVID” results, of which the former is more meaningful.
Two analyses are performed, the simplest being a straightforward count of deaths. In addition, an analysis adjusting for changes in the population and age distribution is undertaken, which given an ageing population is more useful.
On the latter basis, the last two years would have seen a reduction in excess of winter mortality of around 15,000 deaths in total, compared with the previous five year average. We recently published a bulletin on the subject of light excess winter deaths and the possible contribution to excess deaths seen this year. Whilst the purpose, and thus methodology, of the ONS report is different, both demonstrate how the recent level of excess winter deaths is unlikely to form more than a minor factor in the excess deaths seen in 2020.
Source Data: ONS
Estimate of “R”
Finally, for UK data, we present our view of the latest R in England, along with the SAGE estimate for the UK and regional variations.
SAGE estimates the value for the UK to be in the range (0.9 – 1.0) with the same range for England, representing a further fall from last week (1.0 to 1.1). Regionally, most areas are put at below 1, with the NW central estimate at 0.8. However, London and the South East are still predicted to be above 1, with the South East central estimate at 1.1.
Our own estimate for England also shows the value falling below 1 to now stand at around 0.9. This is based on hospital admissions and allows for a typical lag between initial infection and admission. This estimate will be a blend of the various regional positions, and reflect progress made in those areas in tier 3, notably the North West, prior to the national lockdown.
ECDC to Move to Weekly Reporting (link)
Over the last few months we’ve become used to COVID data from many different sources being updated daily. The European Centre for Disease and Prevention Control has been publishing daily updates of cases and deaths from around the world, but has now announced that it will be moving to a weekly update from next month.
Whilst those of us who are data junkies may regret the move to less frequent reporting from ECDC, we should probably spare a thought for those responsible for collating, checking and publishing all the data we receive on a daily basis, and recognise the additional workload and pressure that this has put on those involved.
Daily data from a range of countries will still be available from alternative sources such as Johns Hopkins (link).
It seems that getting lost on a sneaky hike during ‘confinement’ in France is not a good enough excuse to get out of being fined for breaking lockdown rules. Three unlucky hikers had to be picked up by helicopter in the Vaucluse region and promptly had to hand over 135 euros each.