This site is intended for healthcare professionals

Go to /sign-in page

You can view 5 more pages before signing in

Vaccine effectiveness in providing immunity against measles

Last reviewed dd mmm yyyy. Last edited dd mmm yyyy

Authoring team

Vaccine effectiveness:

  • based on available evidence, vaccination with one dose of MMR vaccine is at least 95% effective in preventing clinical measles and 92% effective in preventing secondary cases among household contacts (1)
  • are 2 main types of vaccine failure:
    • primary failure occurs when an individual fails to make an initial immunological response to the vaccine
      • primary vaccine failure is rare, it can occur (particularly after a single dose)
      • in settings with high levels of close interpersonal contact, such as large households or school settings, controlling measles outbreaks requires a high coverage of 2 doses of MMR
    • secondary failure occurs when an individual responds initially but then protection wanes over time
  • term ‘breakthrough measles’ (previously referred to as ‘reinfection’, or secondary vaccine failure) is used to describe a confirmed case of measles in someone who developed immunity to measles, either from natural measles or from prior receipt of measles containing vaccine, typically between 6 and 30 years after infection or immunisation (1)
    • usually associated with intense and/or prolonged exposure to an infected individual, for example, directly caring for an acutely ill person, and so is generally only seen in healthcare workers or in household settings
    • in breakthrough measles are symptoms are generally mild
      • conjunctivitis is generally absent
      • rash may not follow typical progression
      • duration of measles illness tends to be of shorter duration
      • infectivity of these cases is much lower and transient, unlike primary measles infection
        • although polymerase chain reaction (PCR) positive, the presence of neutralising antibodies in respiratory secretions greatly reduces the infectiveness of the virus


  1. UK Health Security Agency (February 2024). National measles guidelines

Create an account to add page annotations

Annotations allow you to add information to this page that would be handy to have on hand during a consultation. E.g. a website or number. This information will always show when you visit this page.