Varicella (chickenpox)

Clinical picture

Varicella (chickenpox) is caused by the varicella zoster virus. Chickenpox occurs as a primary infection and is a highly contagious but generally harmless childhood disease. The symptoms of the disease are more severe in adults and especially in pregnant women. Once the infection has passed, the virus remains latent and can locally relapse in the form of herpes zoster (shingles).

If pregnant women become infected in the first half of their pregnancy (especially between 13-20 weeks), this can lead to congenital varicella syndrome in the foetus; the chance of this occurring is 0.4-2%.

Additional information from the RIVM.

Infection route

The infection occurs through direct (mucous membrane) contact with the vesicular fluid of a chickenpox or herpes zoster patient or through small droplets in the air (aerosols).

Contagious period

Two days before the appearance of the vesicles, until they are dried. The crusts are no longer contagious. Patients with weakened resistance may have an extended period of virus spread.

Incubation time

10-21 days.

Potential infectees

All staff without varicella zoster antibodies who come into contact with chickenpox or herpes zoster patients can be infected by the varicella zoster virus.

Prevention

Pre-employment examination: consider screening candidates for positions in high-risk departments, such as obstetrics, paediatrics, oncology and haematology, for varicella zoster antibodies.

Training: information must be available to staff (e.g. leaflet, intranet).

General measures: Follow up on internal hygiene measures, drawn up by the hospital hygiene department.

Vaccination: Consider offering vaccination to staff (in high-risk departments) who do not have varicella zoster antibodies.

PME: none.

Post-exposure policy

Assess whether an employee has an increased risk of a severe form of the disease and whether additional measures are required.

Potential infectors

Staff who are contagious, who have direct contact with vulnerable patients, such as a staff member without varicella zoster antibodies who has had contact with a chickenpox patient during the incubation period.

A work ban may be necessary for them.