It is a fact of life that people can get ill, and that includes people working in professions such as doctors, dentists, vets, opticians, pharmacists, physiotherapists, and so on: they are not immune.
However, it is not just sickness that results in people taking time off work. They take holidays, too, and people might be called for jury service. They might have to take time off work to look after a family member who is ill or has had an accident. They might suffer an accident themselves. Bereavement can cause people mental issues, and they may need time to sort themselves out.
