Measles outbreak sparks concern over long-term immunity

US public health officials are advising high-risk adults, such as healthcare workers, to get a second MMR dose

Up to 10% of the 695 confirmed measles cases in the US outbreak have occurred in people who received one dose, and even two doses, of the vaccine as children, according to the Centers for Disease Control and Prevention (CDC).

MMR immunisation

The figures have led public health experts, who are battling the country's largest measles outbreak since the virus was eliminated in 2000, to advise high-risk adults who were vaccinated decades to get another MMR dose.

Dr Allison Bartlett, an infectious