How effective is the Chickenpox vaccine at preventing the disease?

emma

If my child gets the recommended two doses of the vaccine, what are the chances they will still get Chickenpox? If a vaccinated person does get a "breakthrough" infection, how mild is it usually compared to the full-blown disease?

isabella

The two-dose varicella vaccine regimen is highly effective, providing over 90% protection against contracting the virus. While there is a small chance (less than 10%) of a "breakthrough" infection, the illness is dramatically milder than the full-blown disease in an unvaccinated person. A vaccinated child with breakthrough chickenpox will usually develop only a small number of red bumps or blisters (often fewer than 50), may have no fever at all, and experiences far less itching and discomfort. The recovery is significantly faster, and the risk of serious complications is reduced to nearly zero. This stark contrast highlights the vaccine's primary value: it transforms what could be a severe childhood illness into a very minor inconvenience.

olivia

After receiving the two recommended doses of the chickenpox vaccine, your child has about a 98–99% chance of being fully protected from the disease. In rare cases where a vaccinated person does get “breakthrough chickenpox,” the illness is typically very mild—with fewer than 50 small spots, little or no fever, and a much shorter duration. These cases also tend to be less contagious. Overall, full vaccination greatly reduces both the risk of catching chickenpox and the severity of symptoms if infection does occur, providing strong and long-lasting protection.