Measles Mumps-Rubella vaccine may help protect children from COVID-19

“What we think is happening is that it affects the front lines of your innate immune system,” Curtis said.

“This is called trained immunity. Cells after exposure to these vaccines are, if necessary, better prepared to cope with subsequent exposure to the virus, and in fact, these vaccines. Being trained by, there is a stronger immune response to fight the virus.

“Children infected with COVID-19 are often coinfected with other viruses. When the virus infection recurs, trained immunity improves and children are more effectively infected with COVID-19. May cause you to. “

The 100-year-old bacillus Calmette Guerlain vaccine, commonly known as BCG, used to prevent tuberculosis also has previously unrecognized effects on the immune system, actually strengthening the immune system and various Infectious disease.

In stark contrast to other respiratory viruses, Curtis said serious illness and death from COVID-19 is rare in children.

“It’s really unusual for us as an infectious disease doctor because this is a complete reversal, as things like the flu are usually worse for children,” he said.

“There is something very different about how this virus causes illness, which tells us that it has great implications for us to understand how to prevent and treat it. There are about 13 reasons we think this will happen. “

Robert Buoy, an infectious disease expert and professor of pediatrics at the University of Sydney, explains why other viruses such as influenza, measles, and chickenpox are far more likely to cause more serious illness in young children than coronaviruses. Said it wasn’t clear yet.

According to one theory, children have been exposed to various types of coronaviruses, such as the common cold, from an early age, which may unknowingly boost their immunity.

Another theory was the idea of ​​”evolutionary superiority”. The child’s immune system is most powerful in adolescence to ensure that the child grows and reproduces.

Curtis found that age-related damage to the thin layers of cells (endothelial cells) that line organs, especially blood vessels, heart, and lymph vessels, significantly increased the risk of serious coronavirus illness. He said he found impressive evidence.

“COVID-19 can infect these endothelial cells, causing inflammation of blood vessels, causing blood clots, and causing strokes and heart attacks,” he said.

“Children’s endothelium is much less damaged than adults, and the coagulation system is different, making children less prone to abnormal blood coagulation.”

Most children infected with SARS-CoV-2 are asymptomatic or have only mild symptoms such as fever, cough, and sore throat.

Whether children are infected with the coronavirus infrequently has been the subject of ongoing debate, but large epidemiological studies suggest that only 1-2 percent of all cases are children. I will.

Curtis said diseases associated with chronic inflammation that develop with age, such as diabetes, obesity, and high blood pressure, are also associated with more severe attacks and higher mortality of COVID-19.

Scientists also say that various levels of microflora (bacteria and other bacteria) in the throat, noise, lungs, and stomach also affect susceptibility to COVID-19, important for immunity, regulation of inflammation, and defense against disease. I believed that I played a role.

“Children are particularly likely to have viruses and bacteria in their nose, and these bugs can limit the growth of COVID-19,” Curtis said.

Vitamin D levels were higher in children who emphasized the theory that anti-inflammatory vitamins could also be pieces of the puzzle.

Curtis said understanding the underlying age-related differences in the severity of COVID-19 provides important insights and opportunities for the prevention and treatment of SARS-CoV-2 infection.

“Initially we were asking why our children were so protected, but then we realized that we were looking at it the wrong way. The children were protected. It’s not just that adults are more vulnerable, “he said.

Professor Curtis is leading a World Health Organization-approved study to test BCG’s ability to prevent coronavirus in healthcare professionals, and the MMR vaccine is being tested in front-line healthcare professionals in the United States. ..