Measles Impairs the Immune System’s Memory: Study
Wed, April 21, 2021

Measles Impairs the Immune System’s Memory: Study

Vaccination causes an immune response in the body in the same manner that a bacteria and virus would. / Photo by luiscarceller via 123rf

 

The main purpose of the immune system is to protect the body from bacteria and viruses. Without it, the viruses would have free reign and the person would be constantly falling ill. From birth, the immune system development of a baby happens each time they get sick because new antibodies are formed. Scientists have even explained that it is also important for children to be exposed to germs and advised parents not to “over-sterilize” their environments.

When protecting a child from serious disease though, vaccinating them is the most effective and safest way. Vaccination causes an immune response in the body in the same manner that a bacteria and virus would. So, when the child comes into contact with the real disease in the future, their immune system will already recognize the virus and germ and respond fast enough to prevent the serious complications to fight off the disease. An example of this would be measles.

 

Immune system amnesia

Two new studies recently revealed that an encounter with the measles virus leaves people with immune system amnesia, which means that the body will be more vulnerable to germs and infections. 

In the first study titled "Incomplete genetic reconstitution of B cell pools contributes to prolonged immunosuppression after measles," which appeared in the journal Science Immunology, researchers Velislava N. Petrova from the Wellcome Sanger Institute Department of Human Genetics and team explained that the immunological consequences of measles can persist up to several years after infection and leads to an increased rate of mortality. They added that the virus wipes out the memory of the immune cells that are supposed to make antibodies.

In the second study titled "Measles virus infection diminishes preexisting antibodies that offer protection from other pathogens," another group of researchers said that the virus can remove up to 73 percent of the child’s preexisting antibodies. When the previously acquired immune system memory is diminished, it can leave the child at risk of infection because of other pathogens, Michael J. Mina from the Howard Hughes Medical Institute Division of Genetics and his group highlighted.

 

The virus wipes out the memory of the immune cells that are supposed to make antibodies. / Photo by Nadezhda Prokudina via 123rf

 

Highlighting the significance of measles vaccination

Together, both studies show the significance of measles vaccination not only to protect the body against the measles virus but for immunity to other pathogens that may be comprised after the body is exposed to real measles infection.

In the second study, Mina and the group cited the recent measles outbreak that happened in the Netherlands that has low vaccination levels. Dutch health authorities said in June via Telegraph UK that the protestant fishing village of Urk was affected. The community there believe that life and death are in God’s hands. Hence, vaccinations are not allowed. Although they refuse vaccinations for religious reasons, they allowed the researchers to take blood samples from school-aged kids. Plasma was likewise collected before and after the confirmed MV infection. Out of the 77 kids, 34 of them had had mild measles and 43 had had severe measles. They then measured the magnitude and diversity of the antibodies in these children and their study controls.

 

Loss of preexisting antibodies

They used the VirScan, a phage-display immunoprecipitation and sequencing technology. It is the technology often used by scientists to determine viral infection history from a single drop of blood. The researchers found that there are certain antibodies in the blood samples that disappeared after they caught measles. In conclusion, the measles virus causes the body to forget the immunity that it has already developed to other diseases in the past. 

In the first study conducted by Petrova and the team, they focused more on the B cells, which are immune cells that pump out the antibodies. They said that after infected by measles, the children already had different B memory cells.

 

 

Child vaccination rates

Intergovernmental economic organization Organisation for Economic Co-operation and Development shared the childhood vaccination rates of certain countries. The data reflects the percentage of kids that receive the vaccination within the recommended time frame of their country.

In the Netherlands, 93.0 percent of children received measles vaccination in 2018. Other countries with high child vaccination rates include Portugal (99 percent), Luxembourg (99 percent), Japan (97 percent), Hungary (99 percent), Greece (97 percent), Finland (96 percent), China (99 percent), Korea (98 percent), Israel (98 percent), Belgium (96 percent), and Switzerland (95 percent).

On the other hand, countries with low child vaccinate rates are Indonesia (78 percent),  South Africa (81.0 percent), Brazil (84 percent), India (84 percent) and Estonia (84 percent).

According to the World Health Organization, even though a cost-effective and safe vaccine is already available, there were still 110,000 measles deaths globally recorded in 2017. Most of the said deaths were among kids under five years old. Measles vaccination between 2000 to 2017 resulted in an 80 percent drop in measles death. Most measles-related deaths are caused by the complications associated with measles, such as an infection that causes brain swelling, dehydration and diarrhea, severe respiratory infections, and ear infections.