High fever, coughing and runny nose, accompanied by inflammation in the nose and throat and the conjunctiva of the eyes, these are the typical symptoms in the first few days after a measles infection. Only then does the characteristic skin rash appear, which first begins on the face and behind the ears and then spreads over the entire body. Measles is highly contagious and can cause serious complications.
New findings on the development of encephalitis after measles infection
Researchers from the University of Kyushu in Japan have now examined the development of one of these complications in more detail and published their results in the journal “Science AdvancesIt is about SSPE (subacute sclerosing panencephalitis), an inflammatory, neurodegenerative disease of the brain after a measles infection. In the case of an infection, the measles virus spreads throughout the body of the person affected, including nerve cells in the brain momentous ability of the measles virus to carry: It can fuse brain cells together.
Death of nerve cells after measles infection
Annette Mankertz, head of the National Reference Center for Measles at the Robert Koch Institute in Berlin, explains the process in more detail: “You can imagine it like this: There is an infected cell in the middle of the brain, in the nerve cells Cells around it make contact. These cells fuse with each other, and then, depending on how many cells come together to form a large giant cell, you end up with a cell that has maybe 8, 10 or even 25 cell nuclei. Of course, that doesn’t work well. One such cell will die.”
The researchers from Japan examined this process in more detail in their study. Because this mechanism is suspected to be the cause of the emergence of SSPE. The researchers found that the measles viruses that remain in the brain after an acute infection change, explains virologist Annette Mankertz. Those affected then carry not only the wild virus, but many different variants of it.
Measles virus mutations influence development of encephalitis
These mutations in the measles virus, which converge in the brain, also in turn change the protein that affects fusion or fusing activity, called the F protein. This results in stronger or weaker activity, depending on which mutations meet and how they interact with each other. This could explain why brain cells become inflamed and die, as is typical of SSPE. These findings by the Japanese researchers could be a first step towards better understanding the mechanism of this late sequela of measles and to treating the disease with medication in the future.