Boris Johnson has said he will not rule out a Plan B of vaccine passports, masks and homeworking.
Here Dr Arthur Hosie, a microbiologist at Staffordshire University, outlines what could plunge the country back into Covid measures this winter…
Sustained transmission in the community
If there are local outbreaks, either due to low vaccine uptake or sustained transmission within schools or social events, then local healthcare will come under unsustainable pressure.
The best way to avoid this is ensuring that all people groups, including the young and vaccine hesitant, are reached by the vaccine campaigns.
Intolerable numbers of Covid related deaths
Although the vaccines have decreased the proportion of people infected with Covid having severe or lethal illness, as case numbers increase the number of deaths will rise.
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Dr Arthur Hosie explains the five factors
Public health measures, including mask wearing, measures to limit social mixing and vaccines will help slow the number of fatalities.
An acceleration in severe Covid case numbers
If we see an upshift in the rate of increase of severe Covid cases this would cause concern.
This may be due to Covid immunity in the population declining, something the vaccine booster programme is designed to prevent, but this depends on uptake.
The NHS is stretched every winter after years of Tory underfunding
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An alternative cause may be a change in the virus biology – a new variant.
A new variant that evades the vaccines
New variants of the virus are arising all the time, but what matters is how more transmissible they are and how severe the disease is that they cause.
The worst case scenario would be a new variant that is able to evade the protection the vaccines provide.
This will necessitate not only plan B to be implemented but also a change in the vaccine, with the need for a further booster campaign.
Other “winter” viruses placing pressure on the NHS
Not only will Covid place strain on the health service, but other winter viruses such as influenza (which causes flu) and norovirus place a tremendous strain on the NHS every year.
We are facing an unpredictable flu season due to the Covid pandemic.
If other infections such as this accumulate on top of rising Covid cases requiring hospitalisation, some form of public heath measures and mitigations will be necessary.