Covid-19 alert levels: What is a level 4 lockdown and how does the UK system work?
AS OMICRON cases continue to rise, the UK's COVID alert system has been raised.
The change to alert level four means transmission of the virus is high as pressure on the NHS mounts.
What is the Covid-19 alert system?
The Prime Minister's 5-point alert system ranks the threat level of the virus on a scale of one (green) to five (red).
The threat level system is adjusted and amended according to medical and scientific data.
Experts analyse data from hospitals along with track and trace information to get an accurate picture of infection rates.
Data used is similar to the figures and information announced on a daily basis.
The system is used in England, Scotland, Wales and Northern Ireland - but are ran independently from each other.
When the alert system was announced, the PM explained: “That Covid alert level will tell us how tough we have to be in our social-distancing measures – the lower the level, the fewer the measures. The higher the level, the tougher and stricter we will have to be.”
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What are the Covid alert levels?
Level 1 - Low: The lowest level of alert would mean that the virus is no longer known to be present in the UK, therefore no restrictions would be needed.
Level 2 - Moderate: There is a low level of transmission and the NHS is operating normally, allowing no or minimal social distancing measures.
Level 3 - Substantial: The virus is in general circulation, but at a level allowing the gradual lifting of some restrictions and social distancing measures.
Level 4 - Severe: The pandemic is in general circulation, with transmission high or rising exponentially but without the NHS being overwhelmed.
Level 5 - Critical: The virus is spreading fast and could overwhelm the NHS, therefore strict measures, such as a lockdown, would be needed.
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Why is the Covid alert level going up?
The Covid alert level has changed because the spread of the virus has been increasing.
The UK moved up to Level four on December 12, as the threat of Omicron rises.
Chief Medical Officers recommended the alert level was raised to four as Omicron poses "a rapidly increasing risk to the public and healthcare services".
In a joint statement, they said early evidence shows Omicron is spreading much faster than Delta and that vaccine protection against symptomatic disease is reduced.
They said: "When vaccine protection is reduced in the way that is happening with Omicron it is essential to top up that protection with a booster.
"Both booster vaccines (Pfizer and Moderna) increase the immune response substantially and show good effectiveness although with some reduction compared to Delta."
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