A new Covid outbreak blighting China is believed to be the dreaded Omicron variant which ruined the Christmas and New Years celebrations of millions of Brits last year.
First detected in November 2021 in South Africa, it quickly spread around the world, becoming the dominant strain of infection.
In Shanghai a new round of Covid outbreaks is feared to be Omicron - one of the most easily transferable variants of the coronavirus - with stringent lockdown measures introduced to fight it.
Unlike the rest of the world which had to battle it without knowing its early warning signs, China has thousands of cases to examine to determine a course of action.
Nine common symptoms associated with it were previously identified for those who have had the vaccine, with another two crucial early warning signs of the infection.
What are the nine symptoms?
Scientists from Norway last year completed a study of guests at a party in November 2021 where Covid had run riot.
Of those who took part in the project, 89% had already received their jab. Of the 111 interviewed 66 had Covid while there were another 15 potential cases.
Thanks to the study the scientists determined the eight main symptoms were:
- Persistent cough
- Runny nose
- Fatigue
- Sore throat
- Headache
- Muscle pain
- Fever
- Sneezing
Experts later added nausea to the list of symptoms people should look out for.
Vaccination also makes it more likely that symptoms will be mild, so it can be difficult to distinguish between coronavirus and a common cold.
What are the two early warning signs of omicron?
The two symptoms which could signal an early warning sign of Omicron are:
- Fatigue
- Dizziness/fainting
It comes as an interactive map was released which shows the Covid red zones where cases are surging in Britain amid a new wave of the virus.
Cases were up 43% in England last week with the fresh uptick expected to last until late summer or early autumn.
Data in the weekly Office for National Statistics (ONS) survey suggests 1.4million people were infected on any given day in the seven days up to June 10.
That's the equivalent of one in 50 - the biggest weekly climb since the end of December last year when Omicron wreaked havoc over New Year's celebrations.
Wales and Northern Ireland had one in 45 and Scotland one in 30 during the same period.
The resurgence appears to be being driven by the BA.4 and BA.5 subvariants of Omicron, believed to be more transmissible than BA.2, which is the current dominant strain in the UK.