The UKHSA document https://www.gov.uk/guidance/people-with-symptoms-of-a-respiratory-infection-including-covid-19 includes the current guidance so please use this link to access this information. The parts of it that most apply to school are below:
Symptoms of respiratory infections, including COVID-19
Respiratory infections can spread easily between people. It is important to be aware of symptoms so you can take action to reduce the risk of spreading your infection to other people.
The symptoms of COVID-19 and other respiratory infections are very similar. It is not possible to tell if you have COVID-19, flu or another respiratory infection based on symptoms alone. Most people with COVID-19 and other respiratory infections will have a relatively mild illness, especially if they have been vaccinated.
If you have symptoms of a respiratory infection, such as COVID-19, and you have a high temperature or you do not feel well enough to go to work or carry out normal activities, you are advised to try to stay at home and avoid contact with other people.
Symptoms of COVID-19, flu and common respiratory infections include:
• continuous cough
• high temperature, fever or chills
• loss of, or change in, your normal sense of taste or smell
• shortness of breath
• unexplained tiredness, lack of energy
• muscle aches or pains that are not due to exercise
• not wanting to eat or not feeling hungry
• headache that is unusual or longer lasting than usual
• sore throat, stuffy or runny nose
• diarrhoea, feeling sick or being sick
When children and young people with symptoms should stay at home and when they can return to education
Children and young people with mild symptoms such as a runny nose, sore throat or slight cough, who are otherwise well, can continue to attend their education setting.
Children and young people who are unwell and have a high temperature should stay at home and avoid contact with other people, where they can. They can go back to school, college or childcare, and resume normal activities when they no longer have a high temperature and they are well enough to attend.
All children and young people with respiratory symptoms should be encouraged to cover their mouth and nose with a disposable tissue when coughing and/or sneezing and to wash their hands after using or disposing of tissues.
It can be difficult to know when to seek help if your child is unwell. If you are worried about your child, especially if they are aged under 2 years old, then you should seek medical help.
What to do if you have a positive COVID-19 test result
Try to stay at home and avoid contact with other people
If you have a positive COVID-19 test result, it is very likely that you have COVID-19 even if you do not have any symptoms. You can pass on the infection to others, even if you have no symptoms.
Many people with COVID-19 will no longer be infectious to others after 5 days. If you have a positive COVID-19 test result, try to stay at home and avoid contact with other people for 5 days after the day you took your test. There is different advice for children and young people aged 18 and under.
Children and young people aged 18 years and under who have a positive test result
It is not recommended that children and young people are tested for COVID-19 unless directed to by a health professional.
If a child or young person has a positive COVID-19 test result they should try to stay at home and avoid contact with other people for 3 days after the day they took the test, if they can. After 3 days, if they feel well and do not have a high temperature, the risk of passing the infection on to others is much lower. This is because children and young people tend to be infectious to other people for less time than adults.
Children and young people who usually go to school, college or childcare and who live with someone who has a positive COVID-19 test result should continue to attend as normal.