Measles infections can wipe out a child’s immune system for up to five years - resetting it to a baby-like state, a study suggests.

Scientists said the virus is so powerful it can trigger “immune amnesia” leaving those who suffer it at far greater long-term risk of picking up flu and other deadly infections.

In some cases the effect is so strong, it is similar to having their entire immune system wiped out.

The research from the Wellcome Sanger Institute, University of Amsterdam looked at 26 unvaccinated children before and after catching measles.

The study, published in Science Immunology found the virus crippled their immunity against other infections for up to five years, even if they had been exposed to them before.

Professor Colin Russell, from the Amsterdam University, said: “For the first time we see that measles resets the immune system and it becomes more baby-like, limiting how well it can respond to new infections.