Chickenpox (known medically as varicella) is an illness that is common in children under the age of 10. Chickenpox is highly infectious and spreads through direct contact and droplet infection (e.g. coughing and sneezing).
The symptoms of chickenpox are:
- fever, tiredness, headache, cough, sore throat and loss of appetite before a rash appears
- a red, extremely itchy rash. The spots that form the rash first turn into fluid-filled blisters and then crust over to form scabs, eventually dropping off.
The incubation for chickenpox is 10-21 days, meaning that symptoms usually appear 10-21 days after infection.
In most children, the scabs fall off after one or two weeks and the child recovers completely, becoming immune to the illness. However, there are some cases when chickenpox can develop into something more serious.
The shingles virus
Over 90% of adults are immune to catching chickenpox because they had the illness as a child. However, the virus lies dormant in the body for many years and can be reactivated as shingles. Shingles causes pain in the area of the affected nerve – often the chest – and can also cause a rash of fluid-filled blisters. Shingles is most common in those over 50 but can happen at any age.
Shingles cannot be ‘caught’ in the same way as chickenpox; you can only develop shingles if you have had chickenpox before. It is more common in people with low immunity and those taking medications that supress their immune systems. However, through direct contact with the oozing blisters of someone with shingles, it is possible to catch chickenpox from someone with shingles. It is not possible to catch shingles from someone with chickenpox.
Chickenpox in adulthood
Adults who have not had chickenpox in childhood can be susceptible to developing chickenpox in adulthood and, if they do, the illness is more likely to be severe and they are more likely to experience complications.
For some groups, such as pregnant women, newborn babies and those with a weakened immune system, catching chickenpox can cause serious problems. In the case of exposure to the virus or the development of chickenpox symptoms in these groups, contact should be made with a GP immediately.
Chickenpox/shingles and work
As chickenpox is so contagious, it can spread very quickly in the workplace, although as mentioned above, most adults are immune to the virus. People with chickenpox are most infectious one or two days before the rash appears, but continue to be infectious until the scabs have crusted over (usually about five or six days after symptoms begin).
People with shingles may be able to continue working, as long as they feel well and are not in too much pain, provided that they don’t work with high risk people and their blisters are covered so that no one else can come into contact with them.
Those with chickenpox should stay away from the workplace until they have been told by their doctor that they are no longer contagious.
If someone who works in a non-healthcare setting develops chickenpox, staff members who have been in contact with the person with chickenpox should be informed. Staff members who have not previously had chickenpox should be warned that they might soon develop symptoms. If they do develop the illness, they may wish to take time off to prevent further spread of the disease.
Those with chickenpox should usually be able to return to work after their scabs have crusted over. During the time in which they are infectious, they should avoid contact with those at high risk of complications from chickenpox and people who have not had chickenpox.
Healthcare workers and chicken pox
Those who work in a healthcare setting and come into contact with someone with chickenpox should take note of the following advice.
Those who are immune to chickenpox (either through having had the disease or having been immunised) should continue working, but if they feel ill or develop a rash, they should contact their occupational health department.
Those who are not sure whether they have had chickenpox should have a blood test to check their immunity. If they are found not to be immune they should:
- report to occupational health if they feel unwell or develop chickenpox symptoms;
- consider getting the chickenpox immunisation.
Healthcare workers who are not sure about their immunity to chickenpox, should check their immunity and get immunised if they are not immune, regardless of whether they have come into contact with the chickenpox virus.
For advice on dealing with chickenpox or shingles in the workplace, call the Fit for Work advice line on 0800 032 6235 (English) or 0800 032 6233 (Welsh).
Employees who have been off work due to sickness for four weeks or more should ask their GP or employer for a referral to Fit for Work. See fitforwork.org for more details.
Those in Scotland can fitforworkscotland.scot or call 0800 019 2211.