An estimated 1.7 million people in the UK had Covid-19 in the week ending 19 December - the highest number since autumn 2020 according to the Office for National Statistics (ONS).
So how worried should we be and how do the two compare?
How fast is the Omicron variant spreading?
Data published on 24 December shows an estimated 35 people in private households in England had the virus in the week ending 19 December - up from one in 45 in the seven days to 16 December.
This is equivalent to 1.5 million people and is the highest estimate for England since the ONS began estimating community infection levels in England in May 2020.
However, Covid-19 infections are now significantly down compared with the peak at the end of 2021 as cases begin to stabilise, with scientists saying the Omicron wave has now peaked in the UK.
Dr Susan Hopkins, chief medical adviser to the UK Health Security Agency, said on Wednesday (19 January) that the latest seven-day average was 93,200 compared with almost 225,000 on 29 December, while hospital cases have dropped to below 20,00.
She said: “This is reflecting our high levels of vaccination in the population and also the reduced severity we have seen with Omicron.”
Dr Susan Hopkins added that case numbers will depend on the removal of Plan B, which is due to expire in England on 26 January.
She added: “We’ve seen cases fall for the last two weeks and that is good news and actually they’re starting to fall all across the country in all regions.
“There is, of course, some age differences – some age groups are seeing plateaus or some still slight rises.
“Therefore, while we believe that overall we will continue to see declines in cases, that may plateau at some point as the infection is in various different populations.
“It’s very hard to see beyond two to three weeks and clearly the biggest change that’s going to happen is people’s behaviour, and how they react to the removal of Plan B will determine how fast infection can spread in the population.
“The biggest response that we all have as individuals is to take our personal behaviour seriously and that really is driving towards vaccination uptake, as well as remembering to wear our face coverings when you’re in closed spaces with people that you don’t know.”
Is Omicron milder than the Delta Covid variant?
The good news is that the Omicron variant is thought to be less likely to lead to serious illness and hospitalisation than the Delta variant, based on reports.
The UK Health Security Agency (UKHSA) estimates that someone infected with Omicron is between 31% and 45% less likely to attend A&E and 50% to 70% less likely to be admitted to hospital than someone who catches the Delta variant.
UKHSA chief executive Dr Jenny Harries said the new data offers “hope”, but warned that it is still too early to downgrade the threat from the new strain, given its rapid spread, and the fact it is now dominant across the UK.
As more cases of the variant have been reported, symptoms have been found to be less severe than previous strains, with effects very similar in nature to the common cold.
What are the symptoms of Omicron?
Patients infected with Omicron have reported symptoms that differ to those associated with the Delta variant and the original Covid-19 strain.
Unlike other Covid-19 variants, a new, continuous cough, a high temperature or fever, or a loss of taste or smell, do not tend to be the most common symptoms.
These three symptoms are considered to be the main indicators of coronavirus infection, but have so far been found to be less common among Omicron cases.
Instead, Omicron has been linked to the following key symptoms:
- Runny nose
- Persistent cough
- Sore throat
Other signs can also include night sweats, fatigue, skin rashes, body aches and pains - particularly in the lower back - and nausea.
Symptoms can be relieved with over-the-counter painkillers, such as paracetamol, and by getting plenty of rest.
As with other Covid-19 strains, Omicron symptoms should only last for around five days.
If you don’t notice any improvement and are worried, you can get help from the NHS online, or call 111 for advice.
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