Exposure to Chickenpox in the Workplace Guide

Overview of chickenpox

Chickenpox is an acute, infectious disease caused by the varicella-zoster virus and is most commonly seen in children under 10 years of age. This virus, if re-activated in a person who has had chickenpox previously, can also cause shingles (herpes zoster), a disease that occurs more often in adults.

Chickenpox may initially begin with cold-like symptoms followed by a high temperature and an intensely itchy, vesicular (fluid-filled blister-like) rash. Clusters of vesicular spots appear over three to five days, mostly over the trunk (the part of the body from the waist up to the neck, excluding the arms) and more sparsely over the limbs. The severity of infection varies and it is possible to be infected but show no symptoms.

Following chickenpox infection, the virus can lie dormant in the body for several years but may reappear following reactivation of the virus as shingles (also called herpes zoster). It is not known what causes the virus to reactivate.

The first sign of shingles is usually pain in the area of the affected nerve (most commonly in the chest). A rash of fluid-filled blisters then appears in the affected area, typically only on one side of the body. This rash is usually present for about seven days although the pain may persist for longer.

How does chickenpox affect staff?

Coming into contact with a person suffering from chickenpox or shingles could result in infection. You can develop chickenpox as a result of exposure to a person with shingles (if contact occurs with a person's oozing blisters).

Chickenpox is highly contagious and infects up to 90% of people who come into contact with the disease. The disease is transmitted through direct person-to-person contact and airborne droplet infection (e.g. coughing and sneezing). The incubation period (time from becoming infected to when symptoms first appear) is about 10 to 21 days. The most infectious period is from one to two days before the rash appears but a person will continue to be infectious until all the lesions have crusted over (commonly about five to six days after the onset of the illness).

Chickenpox is usually a mild illness and most healthy children recover with no complications; however adults, pregnant women and those whose immune systems are compromised due to illness or treatments (e.g. chemotherapy or high-dose steroids) may experience more serious complications.

What are employers' responsibilities?

What employers are expected to do should an employee be diagnosed with chickenpox depends largely on the type of workplace.

In a purely adult, non-care setting, it may be useful for other team members who have had contact with the infected employee to be made aware. The majority of people who have had the disease remain immune for life. Colleagues who do not think that they have previously had chickenpox should be informed that they may develop the disease within 10 to 21 days. If they start to feel unwell within this time period it may be sensible to take time off as soon as symptoms begin (e.g. cold-like symptoms, high temperature) in order to reduce the risk of the disease spreading further.

In care settings it would be prudent to undertake early contact tracing to establish which staff members have had close contact with the person suffering from chickenpox, and who should be immune. Any non-immune employees may need to be excluded from work to reduce transmission to colleagues and the people under their care. They could perhaps be offered the chickenpox vaccine.

Employees suffering from shingles can work if they feel well enough so long as the rash area is well covered and others cannot come into contact with oozing blisters.

Pregnant employees who have a definite history of chickenpox or shingles, or have received two doses of vaccine prior to pregnancy but have come into contact with either of these illnesses during pregnancy, can be offered reassurance that they are not at risk of transmission. However, pregnant employees who have an uncertain or unknown history of chickenpox and have not been vaccinated should inform their midwife/GP or obstetrician urgently.

What help is available for employees?

The Health for Work Adviceline can offer more detailed advice on how to deal with cases of chickenpox or shingles, and whether there are any risks to others from contact at work.

For more information about chickenpox/shingles, and how they can affect your business, or for guidance on other employee health issues, contact the free Health for Work Adviceline on 0800 077 88 44.

You can also contact your union or health and safety representative for advice if you have any issues relating to chickenpox or shingles at work.

Sources of further information

• Information about chickenpox on the websites of the Department of Health, NHS Choices, and the Health Protection Agency.
• The Health Protection Agency's 'Guidance on infection control in schools and other child care settings' can be found on their website.