Unless there is an urgent meeting or project that really cannot be put off or missed, employees should not feel compelled to go into the office when they feel unwell. The chances are that they will under-perform anyway and would be better off recovering at home so that the illness does not drag on or get worse.
In fact, employees who regularly work through illnesses could actually be ignoring signs that their long-term health is suffering and be setting themselves up for problems in the future.
When people are ill or tired, performing a day's work invariably becomes a harder task and stress levels rise, therefore making them even more susceptible to illness.
According to figures from Meridian Stress Management consultancy, 70% of all GP visits are stress-related. Almost 180,000 people die each year from some form of stress-related illness and an estimated 40 million working days are lost each year in the UK for the same reason.
Employees often recognise that they are stressed. A recent study carried out for the Health and Safety Executive found that one in five employees think they are extremely stressed at work, with 23% saying they had suffered an illness in the previous 12 months that was either caused or exacerbated by work.
The IT industry is recognised as being a particularly stressful and often unhealthy environment for people to work in. For many roles, it requires long, unsociable hours, working on time-critical projects under a lot of pressure.
All of this can have a significant impact on a person's long-term health. Yet some employers take a very hard line when it comes to sick leave.
Diane Sinclair, employee relations adviser at the Chartered Institute of Personnel and Development, says employees are perfectly entitled to time off when they are sick. "It is not helpful for either employees or employers if people come in when they are sick. As with any management style, it can damage employee relations and therefore loyalty, performance and creativity if people feel they have to work when sick," she says.
Not allowing or discouraging staff to take time off when they are ill can be counter-productive and result in higher levels of illness and absenteeism overall. It also does not inspire loyalty if a person feels their line manager does not care about their health or well-being. Sinclair says this can lead to a higher turnover of staff and retention problems for companies as employees do not feel valued if they are forced to work when they are genuinely ill.
Some companies - notably US ones - take employee health concerns a step further than just allowing them time off when they are ill. An increasing number allow staff a couple of extra days when they do not have to go into work if they do not feel like it, even if they are not actually sick.
They have become known as "duvet days" - days when people do not feel sick but do not feel like working either. August.One Communications, a PR agency that lists Microsoft as one of its clients, introduced duvet days for its UK workforce four years ago. Each employee is allowed two duvet days a year.
"Duvet days were introduced because we realise that everyone has those days when they just cannot face work," explains Katherine Nicholls, HR manager at August.One. "In the past, these may have been days when people would have called in sick or they may have had to be pre-planned as holiday. The beauty of duvet days is that they are not pre-planned and people do not have to pretend or feel guilty about calling in."
Nicholls says staff are expected to take a responsible approach to when they take their duvet days, and not to choose days when they have important commitments at work.
Duvet days started as a US phenomenon, although they were originally called "mental health days". Perhaps not surprisingly, the term mental health day has since been substituted.