Rationale for Recommending Varicella Vaccination Into the Swedish National Immunisation Programme

Under Swedish law, a vaccination may be included in the National Immunisation Programme (NIP) if it effectively prevents transmission in the population, is cost-effective and aligns with ethical and humanitarian principles. The Public Health Agency of Sweden (PHAS) evaluated these criteria for introducing varicella vaccination.

The evaluation included a literature review, disease modelling to assess dose timing, a health economic analysis and an ethical review addressing vaccine acceptance and equitable access.

Varicella vaccines are safe and highly effective, providing near-complete protection against severe disease requiring hospitalisation when two doses are given. Modelling indicates that virus circulation could be eliminated within 2-3 years with high coverage and catch-up vaccination, also protecting unvaccinated and immunocompromised individuals of all ages through population immunity. Two doses are recommended at 18 months and 7-8 years, both co-administered with MMR. This schedule ensures durable immunity and high acceptance. Health economic analyses show the programme would be cost saving.

Following PHAS's evaluation, the Swedish government has decided to include varicella vaccination in the NIP from 2027, with catch-up vaccination for susceptible individuals up to 18 years, implemented primarily through the child and school health services to ensure equitable access.