The effects of the booster vaccine wane after 10 weeks, according to analysis by the UK Health Security Agency.
However, the good news is that people with Omicron are significantly less likely to develop severe symptoms.
People are 30 to 45% less likely to go to A&E if suffering from Omicron as opposed to the previous Delta variant.
The UK recorded 119,789 new COVID-19 cases which is the highest daily figure since start of pandemic.
Northern Ireland also saw its second highest case figure.