28 January 2021
Lies, Damned Lies and Coronavirus
Visiting Care Homes
by David Chilvers
This week, we visit some of the statistics regarding prevalence of COVID-19 in UK care homes. This was a big problem in the first wave when the discharge of many elderly patients from hospitals into care homes was believed to have been the catalyst for a large number of cases and subsequently deaths. As will be seen, it is likely to be less of a problem in this current wave for a variety of reasons including better procedures and the roll out of the vaccines to this particular vulnerable group.
The Office for National Statistics (ONS) commenced collection of data on COVID-19 deaths in care homes on 10th April last year and so missed the initial part of the first wave of the pandemic.
As can be seen, deaths in care homes represented a large proportion of overall COVID-19 deaths in May last year but as mortality rose in the autumn, care homes seemed to be controlling outbreaks better than previously. However, data for the last couple of weeks shows an increase in both the total number of deaths in care homes and in the proportion of the total COVID-19 deaths that occur in these establishments, albeit care home deaths are a much smaller proportion of the total than in the first wave.
The weekly PHE Flu and COVID Surveillance report contains data on the number of COVID outbreaks in different settings. An outbreak is defined as two or more cases in the same establishment and the number of such outbreaks is then broken down by different types of establishment. The data covers all outbreaks due to respiratory diseases, but from March 2020 onwards the vast majority of these would have been due to COVID-19 (and we therefore use this as a good proxy).
Week 27 is the week ended 5th July last year and this chart shows data up to and including week 2 – week ended 17th January. Several things are revealed by this chart:
- The reduction in outbreaks in educational establishments during the summer and weeks 53/1, the Christmas holidays
- A pick up in outbreaks in educational establishments in the last week as children of key workers and vulnerable children returned to school. There have been a number of reports in the media that the definition of vulnerable children has been extended this term to include many, if not most, that cannot access online learning
- A large pick up in outbreaks in care homes since the Christmas period
The chart below focuses on these outbreaks in care homes, going right back to the start of last year. The rise is steep over the past few weeks and the peak is close to that which occurred in April last year.
Does this rising trend mean that the situation in care homes is as bad as it was in the Spring? The previous data on the lower proportion of deaths contributed by care homes at the moment suggests not and the chart below does confirm that outbreaks are not translating into deaths to the same degree as last Spring.
There is a lag in this data with deaths following outbreaks by some time. The table below shows the correlation between the number of
outbreaks and the number of deaths, with the deaths lagged by 0/1/2/3 weeks:
| Lag | correlation |
| 0 | 0.86 |
| 1 | 0.91 |
| 2 | 0.95 |
| 3 | 0.90 |
The correlation is greatest at two weeks, which ties in with the estimated time it takes for infections to sadly result in death.
Using this time lag of two weeks, deaths per outbreak in the first wave peaked at 2.43, in the first week when data was collected and decline thereafter; it is possible that had data been collected prior to mid April, this ratio would have been higher in the first wave. The largest figure since Christmas has been 2.14, around 15% lower than in the first wave. Applying the multiple of 2 to the number of outbreaks in recent weeks suggests that the number of deaths in care homes may peak between 1,500 and 2,000 per week over the next couple of weeks; this is considerably less than the peak of over 2,500 per week seen in April last year.
This does seem to confirm that although outbreaks of COVID-19 in care homes have increased sharply in recent weeks, the impact on mortality is likely to be considerably less than in the Spring. This is almost certainly due to better procedures in care homes, with PPE being widely available and better controls on the staff going into and out of the homes. And by the end of this week, most care home residents will have received their first vaccine, with several having received both doses (as they were in the first cohort where a gap of three weeks between doses was originally being applied). Vaccination should start to impact on outbreaks in care homes from early February.
We may thus be able to look forward to real visits to loved ones in care homes in the not too distant future, as their level of protection increases along with the decline in case numbers generally and specifically in care homes.
This article is one of a series, find last week’s article “UK Vaccine Roll out” here.
