By Becky Morton.
The news is from the BBC.
The image is from PA Media.
The government warned that up to a quarter of staff could be off work due to rising cases.
The Cabinet Office said that public sector leaders have been asked to prepare for 10%, 20% and 25% absence rates.
There were record numbers of daily cases in the UK over the festive period.
The effect of absences has already been seen.
Large numbers of people are unable to go to work because of rising case numbers. This has affected industries where staff can't work from home.
The Cabinet Office said that Steve Barclay is chairing regular meetings with ministers to assess how the spread of the Omicron variant is affecting workforces and supply chains.
The prime minister asked ministers to test their contingency plans to limit disruption.
Businesses and public services will face disruption in the coming weeks because of the Omicron variant.
His department said that the disruption caused by Omicron has been controlled in most parts of the public sector.
If you test positive for Covid, you must self-isolated in England, Wales and Northern Ireland for at least seven days. Self-isolation can only be ended by two negative flow results in 24 hours.
Positive cases must be isolated for 10 days in Scotland.
In the UK, unvaccinated contacts of positive cases must be isolated for 10 days.
The UK Health Security Agency said that introducing a US-style self-isolation system, where people only have to stay out of public places for five days, would be counter-productive and could lead to more people being exposed.
The two systems were not like-for-like, it said in a post. The self-isolation "clock" in the UK starts when a person experiences symptoms or receives a positive test. In the US, self-isolation begins only after a positive test, which may be a few days after symptoms first appear.
According to the UKHSA, 10% of people will still be infectious if they don't get their test result quickly.
When 5% of people will still be infectious, it says ending self-isolating after seven days with two negative flow tests gives a similar level of protection to self-isolating for 10 days.
Ian Wilson, owner and director of Bellcare, a Cumbria-based firm that provides in- home help for the elderly and disabled, is concerned that people who need care won't get it because there aren't enough people to provide it.
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Ian Wilson, owner and director of Bellcare has been able to increase pay, but there are not enough people to help.
Mr Wilson said that the amount of people requiring care meant that you were run off your feet. "As soon as you start losing staff, it gets really, really awkward."
"If the people don't come forward, it is really difficult, because Bellcare has been able to bring forward an increase in the National Living Wage from April to now," said Mr Wilson.
Mr Wilson's firm has around 120 people and could easily find hours for more than 40 people.
Mr Wilson said that they had overseas workers. It is not going to solve anything next week because we can apply for licences to recruit overseas workers, but that is a lengthy and costly process.
Mr Wilson said he didn't know what the government's plans were for. It is going to be difficult because we can only work with what we have and those people can only work so many hours a day.
The situation will be kept under review, but the UKHSA believes current rules are the best approach at the moment.
In December, the education secretary urged retired teachers to return to classrooms to help with Covid-related staff shortages.
Several train operators have had to reduce services because of staff absences.
The image is from the same source.
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Concerns about staff shortages have prompted retired teachers to return to the classroom.
The number of staff at hospital trusts who have been ill with coronaviruses or self-isolating has doubled in the last week, according to the National Health Service.
Boris Johnson should have told ministers to plan for workplace absences weeks ago, said Labour's deputy leader.
Boris Johnson's lack of leadership means his government has been delayed and left contingency planning to the last moment.
With record Covid infections, the prime minister needs to get a grip on workforce pressures, keep essential services moving, keep schools open and keep people safe.
Businesses say this proposal from the government is good, but they would like to see more detail on what contingency planning would mean in practice.
If their teams become ill, where will more staff come from?
Russell Norman had to close his popular restaurant in London before the New Year after his staff fell ill with Omicron and his workforce plummeted from 24 to just five.
He says that there are not as many enthusiastic people waiting in the wings who are available for restaurant work.
There's another worry as well.
Many of their staff are on zero hours contracts and have seen their hours slashed because of falling consumer confidence and venues closing.
Industry leaders think that some will continue to work even if they are positive.
The number of new cases in England on Saturday was a record for the fifth day in a row, and Covid hospital admissions were at their highest level in over a year.
Scotland, Wales and Northern Ireland did not report on Saturday.
Plan B restrictions include mandatory masks in most indoor public places, Covid passes for nightclubs and other large venues, and guidance to work from home if possible.
The measures are set to expire six weeks after implementation, with a review after three weeks, which is expected on or close to 4 January.
Sajid Javid said that any additional restrictions in England must be an absolute last resort.
