Measles: infection clears immune memory and makes you more susceptible to other diseases
According to experts, measles is one of the most contagious infectious diseases in humans and involves high rates of complications and complications. The infections can even be fatal. An international research team has now found that the dangerous viruses can partially wipe out the immune memory. Affected people become more susceptible to other pathogens.
Measles infections can cause serious illnesses that can also be fatal. Researchers from the Paul Ehrlich Institute (PEI), in collaboration with scientists from Great Britain and the Netherlands, have now found that measles viruses erase part of the immunological memory over the years. As it says in a message, affected people become more susceptible to infections with other pathogens even after the measles infection period. The research results are reported in the journal "Science Immunology".
Germany shares responsibility for the increase in measles diseases
Although measles should have been eradicated long ago since vaccination was introduced around 40 years ago, infections are even increasing again. According to the PEI, almost three times more cases were reported worldwide in the first six months of 2019 than in the same period last year. The European Center for Disease Prevention and Control (ECDC) speaks of a resurgence of measles in the European Union and in the European Economic Area (EEA). According to the information, five countries are primarily responsible for this, including Germany, in which transmissions are still endemic - i.e. within the population.
Measles virus weakens the immune system against other pathogens
It has long been known that measles infection can not only be very difficult and even fatal, but that measles virus also weakens the patient's immune system against other pathogens. A measles infection often leads to other infections such as bacterial pneumonia or middle ear infections. A recent measles cohort study conducted in the UK showed that ten to 15 percent of children had signs of significant immune system impairment five years after a measles infection, leading to an increased incidence of secondary (further) infections.
Composition and diversity of memory cells in vaccinated people stable
A research team led by Prof. Veronika von Messling, head of the veterinary medicine department of the PEI, Federal Institute for Vaccines and Biomedical Medicines until September 2018, has investigated which mechanisms within the German Center for Infection Research (DZIF) together with scientists from Great Britain and the Netherlands lead to this immunosuppression.
For this purpose, the researchers analyzed the receptor diversity of the immune cells and the development of an important group of immune cells for immune memory, B memory cells, in unvaccinated people with and without previous measles infection and in people vaccinated against measles. While the genetic composition and diversity of B memory cells was stable in people without measles infection and in vaccinated people, there was a significant increase in the frequency of mutations in these cells and a changed isotype (variation) profile in people after measles infections.
According to the information, the diversity of the immune cells was even very severely impaired in the study in around ten percent of people infected with measles. There was also a shift towards immunologically immature B cells, which indicates an impaired B cell maturation in the bone marrow.
Measles vaccination protects
As stated in the communication, the results confirm that the immune system virtually forgets after a measles infection which pathogens it had previously come into contact with. There is a so-called "immunamnesia". Scientists at the PEI confirmed these findings in the animal model (ferret). The animals were initially immunized against influenza (flu) and some animals were infected with a mutant canine distemper virus (CDV), which is related to the measles virus.
According to the researchers, the animals infected with CDV lost most of the antibodies against influenza and had a more severe course of the disease than animals not previously infected with CDV when they were later infected with the influenza virus. “Measles vaccination is not only important for protection against measles viruses, but also protects against the occurrence or severe course of other infectious diseases. It protects the immune memory, which can be severely impaired in measles infections, ”explains Prof. Klaus Cichutek, President of the Paul Ehrlich Institute.
In Germany, measles vaccination will become compulsory for some groups of people in the coming year. According to the Federal Ministry of Health (BMG), it is stipulated that “all children must have both measles vaccinations recommended by the Permanent Vaccination Commission when entering school or kindergarten. Proof of measles vaccination must also be provided when looking after a childminder. ”The same applies to people who work in community facilities or medical facilities such as educators, teachers, day care workers and medical staff (insofar as these people were born after 1970). Asylum seekers and refugees must also provide proof of vaccination protection four weeks after admission to community accommodation. (ad)
Author and source information
This text corresponds to the specifications of the medical literature, medical guidelines and current studies and has been checked by medical doctors.
- Paul Ehrlich Institute: Measles infection clears immune memory - measles vaccination protects, (accessed: November 2, 2019), Paul Ehrlich Institute
- Science Immunology: Incomplete genetic reconstitution of B cell pools contributes to prolonged immunosuppression after measles, (accessed: November 2, 2019), Science Immunology
- Federal Ministry of Health: Obligation to vaccinate should protect children from measles, (accessed: 02.11.2019), Federal Ministry of Health