There will be a significant impact on employees and the self-employed who are asked to self-isolate if they have symptoms of the virus, or if others in their household do, or if they take time off sick with the virus.
The Government guidance for employees linked below includes the following:
Staying at home - https://www.gov.uk/government/publications/guidance-to-employers-and-businesses-about-covid-19/covid-19-guidance-for-employees#staying-at-home
Working from home - https://www.gov.uk/government/publications/guidance-to-employers-and-businesses-about-covid-19/covid-19-guidance-for-employees#working-from-home