Covid booster jabs remain the strongest defence against Omicron, as the new variant continues to spread rapidly across the UK.
But while this means better protection, those who have had three jabs can still contact Covid-19.
Generally, people who have reported Omicron symptoms have likened them to those you might get with a cold.
READ MORE: Four Omicron symptoms in children you should never ignore
Researchers from the ZOE app - the world's largest ongoing study of Covid-19 - found the five most-reported symptoms to be a runny nose, headache, fatigue, sneezing and a sore throat.
The UK Health Security Agency estimates people should have around 70-75% protection against the virus after having a third jab.
This means those who have had all three jabs could still contract the virus - and can experience symptoms with Omicron.
One New York-based ER doctor took to Twitter to share the "uncomfortable" symptoms identified in those who have contracted the variant after having had a booster dose.
Doctor Craig Spencer discussed the "mild" symptoms he was seeing in people who had had three jabs.
Dr Spencer said: "Every patient I’ve seen with covid that’s had a third ‘booster’ dose has had mild symptoms.
"By mild I mean mostly sore throat. Lots of sore throat.
"Also some fatigue, maybe some muscle pain. No difficulty breathing. No shortness of breath. All a little uncomfortable, but fine."
The Government has never updated guidance on covid symptoms beyond the three classic symptoms (high temperature, a loss or change to smell or taste, and a new and continuous cough).
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