Children's immune system weakened for up to 3 years after measles infection

"We already knew that measles attacks immune memory, and that it was immunosuppressive for a short amount of time. But this paper suggests that immune suppression lasts much longer than previously suspected," says study co-author C. Jessica Metcalf, assistant professor of ecology and evolutionary biology and public affairs at Princeton University, NJ.

"In other words," she adds, "if you get measles, 3 years down the road, you could die from something that you would not die from had you not been infected with measles."

There has been much focus on measles of late. Though the virus was declared eliminated from the US in 2000, the number of measles cases in the country has started to rise. Last year saw 644 measles cases reported - the highest number since elimination - and this year has seen 169 cases reported so far.

The recent measles epidemic in the US has been primarily attributed to lack of vaccination against the virus. A Spotlight from Medical News Today in February investigated the issue, finding that many people remain concerned about the safety of the measles, mumps and rubella (MMR) vaccine, which may be deterring parents from getting their children vaccinated.

Metcalf and colleagues say their study, recently published in the journal Science, highlights the importance of the measles vaccine, stating that it could also protect against an array of other diseases.

"It is one of the most cost-effective interventions for global health," says lead study author Michael Mina, a former postdoctoral research at Princeton who is now a student at Emory University in Atlanta, GA.

Mina says he was inspired to pursue this latest study after he came across a study by researchers from Erasmus University Medical Center in the Netherlands, which demonstrated strong links between the measles virus and a reduction in immune memory cells.

That study showed that the measles virus attacks and destroys T cells, or T lymphocytes - a type of white blood cell in the immune system that protects against diseases by remembering foreign bodies that have crossed its path.

The research showed that while the T cells return in around 1 month, they only fight off the measles virus, almost ignoring all other pathogens they previously confronted.