Epidemiology of varicella zoster virus in the Netherlands : Implications for vaccination strategies

Abstract

Varicella and herpes zoster are caused by the varicella zoster virus (VZV). At the first contact with this virus you will get varicella. Subsequently, the virus remains latent in your body and can become active again years later, presenting as herpes zoster. In the Netherlands, almost everyone gets varicella at a relatively young age, when varicella usually has a benign course. The life-time risk of herpes zoster is estimated at 23–30% and is higher in old age. Vaccination is the only way to prevent varicella and herpes zoster. This thesis focuses on questions and barriers regarding the introduction of vaccination against varicella and herpes zoster in the Netherlands. Introducing varicella vaccination in the Netherlands may also have negative consequences: 1) the age at which varicella occurs may increase, resulting in a more severe course of the infection and 2) the number of herpes zoster cases may temporarily increase due to diminished exposure to the virus and thus reduced stimulation of the immunity against the virus. The relatively low individual varicella disease burden in the Netherlands and the uncertainties about negative consequences of vaccination could be a reason to wait with the introduction of universal varicella vaccination, and limit this to risk groups or other scenarios, and to learn from experiences from other countries where it has been introduced. The Health Council recently gave positive advice on herpes zoster vaccination in the Netherlands, provided that it’s cost-effectiveness improves. Advice on varicella vaccination is currently being prepared by the Health Council.