A Member of the Senedd has warned that the north of Wales is at a high risk of a second wave of Covid-19 if the Welsh Government relaxes the lockdown.
Of the 133 new cases announced in Wales yesterday, more than half were in the Betsi Cadwaladr Health Board region.
Llyr Gruffydd said a new statistical analysis showed that the R value in the Betsi Cadwaladr Health Board region was ‘worryingly’ higher than other parts of the country.
It needed to come down significantly before any lockdown restrictions could be lifted, he said, and that any difference with other parts of the country should not be overlooked by government.
“Messages from Cardiff and Westminster governments that Covid-19 virus illness is reducing are overlooking regional differences,” Plaid Cymru MS Llyr Gruffydd said. “That is a particular concern for north Wales.
“Last week the Welsh Government issued a ‘technical update’ to illustrate how, in Wales as a whole, the rate at which each person infected by the virus passed it on to other people had reduced substantially.
“In late March any person carrying the virus was likely to infect nearly three other people giving a rate of infection R of 2.8 to 1.”
The Welsh Government has published a Technical Advisory Cell Modelling Update in which its statisticians have estimated the rate of infection during the lockdown. The report states:
“All contributors use a different methodology for modelling R and their results are brought together for a consensus view. The models use new hospital admissions where the patient has tested positive for COVID-19, new confirmed cases (where a patient has been tested positive for COVID-19), and deaths where the deceased has been tested positive for COVID-19”.
The data is tracked over time to show the relative change in the R measure. The Technical Advisory Cell states that R is now between 0.7 and 0.9 in Wales as a whole, meaning that for every ten people that are infected, seven or nine further people will be infected. That would mean that, in Wales as a whole, the number of Covid-19 cases is slowly declining.
But the R rate in different parts of Wales varies as the virus arrived at different times in different regions. However, the Technical Advisory Cell has not produced any R estimate for the north Wales the Betsi Cadwaladr Health Board area.
The First Minister told Wrexham.com that: “That isn’t to say, we know that the virus has taken a different course in some parts of Wales. It runs in a different way in urban and rural places.”
But the First Minister declined to have his Technical Advisory Cell produce a seperate estimate for the north of Wales, saying: “We act in this way as a single nation”.
Retired Management Consultant Tom Brooks, who has experience of epidemiological modelling in various parts of the world, said that his modelling suggested R had pushed back over 1 in the Betsi Cadwaladr area.
“Various sources of data are available for calculating the R number, as acknowledged by the Technical Advisory Group,” he said.
“Public Health Wales publishes a Coronavirus dashboard which includes ‘numbers of confirmed tested cases’, ‘number of cases suspected by GPs from consultations in clinics’, ‘the number of persons suspected of having the virus in triage calls with NHS 111’,etc. Other sources of survey data are available such as the KCL and Zoe Global Covid symptom study.
“The Office of National Statistics publishes details of deaths which are considered on registration to have a Covid-19 factor. Care Inspectorate Wales publishes figures in relation to care home mortalities involving Covid-19.
“All of these are available at the Betsi Cadwaladr regional level and are sufficient to model the infection rate with a good level of confidence. The R rate had been down to under 0.9 in north Wales by early May, but the increased viral activity and cases this month have now pushed it back near to 1.
“The case activity reports from May 7 to May 10 have been most concerning. All measures have caused concern, but the positive tested case figures illustrate the outlier state of the virus in north Wales. 238 new positive tested cases were recorded in four days; this is a huge increase for North Wales.
“Current cases are higher than the 222 positive tested cases announced on the four days April 18 to 21, then at the peak of the pandemic in North Wales. 35% of confirmed cases in Wales are now in the North. In the last two and a half weeks most parts of the UK, including south Wales has seen a steady reduction in the incidence of Covid-19 due to the application of lockdown measures. Why not north Wales?”
Tom Brooks added that the differential in the R rate, although seemingly minor, had the potential to increase the number of deaths in the region by thousands in the coming months.
“The difference for north Wales as to whether R goes down to 0.9, stays at 1 or goes up to 1.1 is dramatic. The Technical Advisory Group have produced a table demonstrating the difference in impact that different levels of R make.
When their figures are scaled to the current level of infection in the north, he said, the table reads:
“That would mean an additional 2240 deaths in north Wales alone if the R value increases to 1.1,” Tom Brooks said.
“No allowance is made in these figures for steadily improving healthcare management of confirmed cases in our hospitals and a subsequent lower mortality rate. However, if we continue as at present at R near to 1, close to 1,000 more families in north Wales will lose a loved one. Allowing R to exceed 1 should not be contemplated.
“North Wales urgently needs to launch its test, track and trace programme to drive R to lower levels and spare the population. With the high incidence of Covid-19 in north Wales, we should be the priority for Wales for track and trace.”