The measles virus is generally thought of as relatively harmless by most people even though it is one of the leading causes of death among young children. It can cause fever, cough, rash, and in young children or adults can result in pneumonia and swelling of the brain. Measles is 100% preventable with a safe and effective vaccine but still people refuse to get the shot. The general idea that measles is relatively harmless is often cited as a reason why people who are wary of vaccines refuse the immunization. Instead, some people choose to have their children catch measles and build a ‘natural’ immunity to it. That line of reasoning is flawed and dangerous and new research suggests that getting sick with measles causes more problems than we originally thought. It turns out the measles virus can wipe out your immune system’s memory and open you up to a whole host of other infections.
The measles vaccine was introduced 50 years ago. When immunizations against the disease began, people noticed a striking decrease in the childhood death rate from a range of infectious diseases and not just measles. These kids were getting a vaccine for one disease but it seemed to be protecting them from a whole bunch of other infectious diseases (see below).
The measles deaths (dotted line) decreased after the introduction of the vaccine (blue vertical line) but so did the deaths by all other non-measles infections (solid line). Why is that? The vaccine only protects against measles and the reason for this seemingly broad protection remained a mystery until recently. Researchers from Atlanta, publishing in the journal Science have identified how a measles vaccine can protect you and your children from a whole host of diseases.
It comes down to how the measles virus works. Measles infects the white blood cells in your body that are responsible for not only mounting your immune response but also the ones that are responsible for remembering how to fight the different invaders. Researchers working on measles infections in monkeys found that the measles virus wipes out all the memory cells the body has accumulated over the years. This, in theory, would leave the body vulnerable to all the infections it had built up immunity to. They called this immune amnesia. The researchers from Atlanta took the idea one step further and discovered that this immune amnesia happens in people. They predicted and saw that the number of deaths due to infectious disease rose and fell with the number of measles cases each year. The effect was so pronounced that in any given year, the number of children who died from an infectious disease was directly related to the number of measles cases in the previous 2 to 3 years. The researchers concluded that a measles infection in a toddler resulted in their immune system being reset back to that of a newborn. This means that those children would then have to be exposed to the same bacteria or viruses in order to get back all their immunity again.
The research is fascinating as it provides and explanation for why measles vaccines seem to be protective against most other infectious diseases. However, there is potentially frightening implications about the results. Some parents shun the MMR vaccines because of false fears over its association with autism. These children can then catch the measles virus and all the immunity they have built up will be wiped out. Any vaccines they did get as children will be rendered ineffective and they will need to be immunized again or risk getting the infection later in life where they are often more severe. Things like chicken pox or a simple cold suddenly become more severe because your immune system has no information on how to fight them. Get the measles vaccines because it protects against more than just measles. It can prevent other potentially lethal infections from taking hold of your children.