COVID-19: HOW WELL DID THE WELSH FIREBREAK WORK?

The FireBreak in Wales lasted 17 days from Friday 23 October, as schools broke up for half term, and finished on Sunday 8 November.  New restrictions started on 9 November.  That's three weekends and two working weeks, where all the younger age groups went back to school for a week.  How well did that work in reducing infection rates?

As symptoms first appear typically after around 5 days, with tests of symptomatic people being delayed by a further couple of days, say a week in total.  So the effect of the FireBreak on infection rates would be apparent between about 29 October and 14 November.

THE ZOE & KINGS COLLEGE LONDON "COVID SYMPTOM STUDY REPORT"

Some 4 million people across the UK have loaded the ZOE app onto their smartphones.  The report on 22 November covering the period to 18 November showed this graph of new infections for Wales, which has flattened off in the two days since:

The graph is an average for the two weeks up until the specified date.  A day that had a larger number of new cases compared to two weeks previously will show as an increase, and a lower number as a decrease.  

The graph shows the FireBreak starting and finishing its effect as expected around 29 October and 14 November, after which cases have started to rise again.  The overall effect was for new cases to halve in those 17 days. 

Whilst the app only covers people with a smartphone, it has the advantage of not being dependent on the level of testing.

THE ONS COVID-19 INFECTION SURVEY

The Office of National Statistics has expanded its randomised testing programme, but its latest report on 20 November says of Wales that despite "... the relatively small number of tests" "Our modelling suggests that positivity rates in Wales peaked around the end of October, with rates decreasing over the past two weeks. This is based on exploratory modelling of throat and nose swab results."

PUBLIC HEALTH WALES STATISTICS

Statistics from testing of symptomatic people, modelled by BBC, also show the infection rates across Wales peaked around 29 October and had stabilised around 14 November:

 

Virtually all areas have achieved a reduced level of infections.  Even the brown areas of South Wales have improved, often moving from the top of the 200-500 range to the bottom without changing colour:

 

The FireBreak has clearly worked in reducing the level of infections:

• The higher the starting rate of infections, the greater the drop in infection rates
  
• For high-infection areas with a reduction down to some one third of the peak level
• For other areas, mostly down to about a half
• Though some areas that started under 100 cases a day per hundred thousand didn't reduce substantially
  

Update 1 December:  However infection rates have started rising again since the end of the FireBreak, requiring new tight restrictions announced 30 November.

IN CONCLUSION

The Welsh FireBreak worked in reducing daily new cases by about a half overall, being higher in areas of high infection and less in lower areas.

That still left daily new cases running much higher than ideal, hence the need for further restrictions since 9 November.  Those restrictions have not proved to be sufficient to avoid increases, and infection rates have since risen in most regions of Wales.

It is clear that the Firebreak needed to be:

• Slightly longer, the full three weeks, or 
• A sharper set of restrictions, including leaving all schools shut for the whole period
  

Certainly the reduction in cases was not as great as achieved in the first national lockdown in March/April, as analysed here.