The latest variant of Covid-19 has begun to spread in the UK, with the number of confirmed cases nearly doubling between Wednesday and Thursday.
A total of 817 cases of the omicron variant of Covid have now been recorded in the UK, with 249 new infections recorded on Thursday.
Prime Minister Boris Johnson said in his press briefing on Wednesday that the variant’s doubling rate could be between two to three days due to the fact that the variant is highly infectious.
Are vaccines effective against omicron?
Results from preliminary studies by the German Centre for Infection Research found that there were significant reductions in antibody potency for the Pfizer/BioNTech, Moderna and Oxford/AstraZeneca vaccines against omicron.
However, two doses of a vaccine should have some protection from severe disease with the World Health Organisation suggesting that “current vaccines remain effective against severe disease and death”.
Prof Uğur Şahin, the CEO and co-founder of BioNTech, said on Wednesday: “Individuals who have received two vaccines will most likely not have a significant prevention from infection or any type of disease. We know they will have memory T-cells, which may prevent severe disease.”
In the first official briefing from vaccine manufacturers on how likely their shots are to be effective against omicron, Prof Şahin said that accelerating booster programmes was “the right way to go” and suggested that an extra dose of a vaccine does appear to compensate for the vaccine being less well matched to combat Covid, compared to other earlier strains of the virus.
A preliminary study from the Africa Health Research Institute in South Africa, which was released on Tuesday, found there was a 41-fold reduction in the potency of antibodies after two doses of Pfizer against omicron.
Although these results showed a “much more extensive escape”, the researchers wrote that “previous infection, followed by vaccination or booster is likely to increase the neutralisation level and likely confer protection from severe disease in omicron infection.”
Prof Alex Sigal, a professor at the Africa Health Research Institute, said on Twitter that the results were “better than I expected of omicron”, adding: “The fact that it still needs the ACE2 receptor and that escape is incomplete means it’s a tractable problem with the tools [we’ve] got.”
Are some types of vaccine more effective than others?
A small study has suggested that the omicron coronavirus variant may be able to better evade the protection offered by the Pfizer/BioNTech vaccine than the initial Covid virus type.
There seems to be a “very large drop” in immunity against the new variant among those given Pfizer’s vaccine, said Prof Sigal after his laboratory studied the blood samples of 12 people who had been vaccinated with the jab.
Moderna is yet to publish any official results on the efficacy of its jab against omicron but president of the company, Dr Stephen Hoge, said there’s a good chance current vaccines won’t hold up as well against the variant.
Speaking to ABC News on Sunday, Mr Hoge said: "I think that there’s a real risk that we’re going to see a decrease in the effectiveness of the vaccines.”
He added: "What I don’t know is how substantial that is."
Will a new omicron vaccine be released?
Vaccine makers have said that they will continue “at full speed” with plans to develop an updated omicron-based vaccine, which should be available by March 2022 if needed.
Pfizer said last week that if needed it could produce an omicron-tailored vaccine in "approximately 100 days”.
Prof Şahin said: “We continue to work on an adapted vaccine which, we believe, will help to induce a high level of protection against omicron-induced Covid-19 disease as well as a prolonged protection compared to the current vaccine.”
Meanwhile, Moderna’s chief medical officer, Dr Paul Burton, said last week that it would take three months for Moderna to produce a vaccine specifically targeting omicron.
Johnson & Johnson is currently testing its vaccine against omicron with Dr Mathai Mammen, the global head of research and development for the company, saying in a statement: “We have begun work to design and develop a new vaccine against omicron and will rapidly progress it into clinical studies if needed.”
The company is however yet to give a timeline for vaccine development.
AstraZeneca hasn’t revealed whether or not it will need to develop a new vaccine against omicron.
However, Oxford professor Sarah Gilbert, who helped create AstraZeneca’s current jab, has said that existing coronavirus vaccinations, no matter who produced them, are not likely to perform well against omicron.
"Until we know more, we should be cautious, and take steps to slow down the spread of this new variant," she told the BBC on Monday.
How many jabs will we need?
It is thought that three doses of the Pfizer/BioNTech vaccine are likely to protect against infection from the omicron variant, initial Pfizer laboratory data has suggested, although this is yet to be peer reviewed.
Two doses of the vaccine may prevent severe disease, but cannot be guaranteed to prevent people from contracting Covid.
The CEO of Pfizer suggested that a fourth dose of the vaccine might be necessary for better protection against omicron.
Speaking on CNBC’s Squawk Box, Albert Bourla said the company was waiting to see real-world data to decide whether or not further doses would be required specifically to combat omicron.
He said: “When we see real-world data, [we] will determine if the omicron is well covered by the third dose and for how long. And the second point, I think we will need a fourth dose.”
He went on to suggest that data could be expected in the next two weeks.
What are the symptoms of omicron?
Omicron often causes mild symptoms so it may be difficult to tell whether or not you have a cold or Covid.
Symptoms, such as stuffy nose, sore head and sore throat are applicable to both Covid and the common cold making it is very hard to tell the difference without taking a test.
Professor Tim Spector, from Britain’s Covid Zoe app, said that data from the Zoe study suggests that about half of all cases of delta are being “missed” as they are not showing up with “classic” Covid symptoms of fever, new and persistent cough and a loss or change of smell or taste.
“Omicron is probably more, much more similar to the mild variants we’re seeing in people who have been vaccinated with delta than anything else,” he said.
