Friday, May 8, 2015

Measles leads to other diseases through "immune amnesia"

New Scientist reports:

Measles is often painted as a trivial disease by the anti-vaccination movement. It is not – it kills or causes brain damage in two or three out of every 1000 cases, even in wealthy countries. Here's another reason it isn't trivial: having measles destroys your immunity to other diseases – and some of those are far more deadly. The upshot? Getting your child vaccinated will protect them from much more than just measles. . . .

The measles virus is known to kill the white blood cells that have a "memory" of past infections and so give you immunity to them. It had been thought that those cells quickly bounce back, because new ones appear a week or two after someone gets over measles. However, recent work in monkeys that have recovered from measles shows that these new memory cells only remember measles itself; the monkeys lose cells that recognise other infections. If humans get similar "immune amnesia" after measles, childhood deaths from infectious diseases should rise and fall depending on how many had measles recently, and how long the effect lasts. . . .

The prospect of a child losing its hard-won immunity to a host of threatening diseases might be the nudge some parents need to recognise that the measles vaccine is essential.