Getting vaccinated against infection not only protects against the virus, but prevents the body’s shield from losing its defenses for three years

Three years exposed to any infection, even the slightest leave a huge mark on the body, and even jeopardize its functioning. This is one of the conclusions reached by two new studies published in the journal “Science” on the benefits of measles vaccination. “It has always been suspected that immunizing against the infection had benefits beyond it. Because it was observed that there was less incidence of other viral and bacterial pathologies”, explains Ruth Figueroa belonging to the OSI Bilbao-Basurto Microbiology and Infection Control Service of the Basque Country and president of theVaccine Working Group of the Spanish Society of Infectious Diseases and Clinical Microbiology (Seimc).

Measles erases the memory of the immune system

The article summarizes that during the last decade enough evidence has accumulated that the measles vaccine protects not in one way, but two ways: it not only prevents the known acute disease with spots and fever that often sends children to the hospital – because it is lethal in one in every thousand cases–, it also seems to help against other long-term infections.

As Federico Martinón-Torres, head of the Pediatrics Service and director of Pediatric Clinical, Infectological and Translational Research at the University Clinical Hospital of Santiago de Compostela , says, “some research, such as this one, has pointed out that immunization strengthens the system in general immune. In addition, they have hypothesized that the extended protective effects of it come from the prevention of measles infection. According to this theory, the virus can damage the body’s immune memory, causing the so-called immune amnesia. By protecting against the pathogen, the vaccine prevents the body from losing or “forgetting” its immune memoryand preserves its resistance to other infections. Some previous work has already been hinting at the existence of effects of the absence of memories, showing that immune suppression after measles infection could last up to two or three years.

Why is it altered?

This last work belongs to a group of the Harvard University School of Medicine (USA) . Researchers show that measles virus eliminates 11 to 73% of the different antibodies that protect against viral and bacterial strains that a person with a complete immune system, from influenza to herpes viruses and bacteria that cause pneumonia and infections of the skin. So, if a person had 100 different antibodies against chickenpox before contracting measles, it could be reduced to only 50 after its passage, halving its protection against chickenpox. That protection would decrease further if some of the lost organisms are potent defenses known as neutralizing antibodies.

Michael Mina, research assistant professor of epidemiology at Harvard TH Chan School of Public Health, stresses that “so far this is the best evidence that there is an immune amnesia that impacts the memory of the immune system in the long term.” Or as Martinón-Torres explains: «This shows that one who learns to run a marathon can suddenly travel shorter distances. He does it because he knows. The same happens with the vaccine, which is why it is so important. Because when the measles virus attacks the organism, it defends itself against it, but ends up exhausted and even if the person is well – without spots and without fever – what he does not know is that he has stayed for a period of almost three years without defenses for the next infection. Hence we sometimes hear “measles passed and died of the flu.”

Since measles figures have experienced a rebound in recent years due to the decline in vaccination – when both doses protect 99% against infection -, and the World Health Organization (WHO) has warned of a new The epidemic wave in countries such as the United Kingdom, Greece, Albania and the Czech Republic, this work is especially relevant. “The threat posed by infectious pathology to people is much greater than we previously imagined,” said lead author Stephen Elledge, Professor of Genetics and Medicine at the Blavatnik Institute at Harvard Medical School and Brigham and Women’s Hospital. “We now understand that the mechanism is a prolonged danger due to the elimination of immune memory, which shows that the measles vaccine is even more beneficial than we knew,” concludes Elledge.