Self-isolation is a crucial step to prevent the spread of infectious diseases. If your colleague is feeling unwell, it is important to advise them to stay at home until they are feeling better. This will help to prevent the spread of any potential illness to others in the workplace.
Respiratory etiquette is also important to prevent the spread of infectious diseases. Your colleague should be advised to cover their mouth with their elbow when they need to cough or sneeze. This will help to prevent the spread of any respiratory droplets that may contain infectious agents. Additionally, they should turn away from others when they need to cough or sneeze to further reduce the risk of transmission.