AuthorWrite something about yourself. No need to be fancy, just an overview. ArchivesCategories |
Back to Blog
Mono symptoms in adults12/28/2023 As for the one case of MS in someone who remained negative for Epstein-Barr, it is possible that person was infected after the sample was taken, but it is also true that, in diseases that are clinically defined by their symptoms, such as MS, it is highly unlikely that 100 percent of cases derive from the same cause, even if most do, Ascherio says. The risk of developing MS was 32 times greater for those who seroconverted by the third sample, compared with those who did not. Only one of the 801 people with MS had not been infected with Epstein-Barr before the disease’s onset. Thirty-five of the people who developed MS and 107 controls tested negative for EBV initially. Out of the 955 cases of MS, they were able to assemble appropriate samples for 801 individuals with the disease and 1,566 controls. Each person with MS was also matched with two randomly selected controls without MS, who were of the same age, sex, race or ethnicity, and branch of the military. The team was looking for seroconversion, or the appearance of antibodies in the blood as evidence of infection. In the new study, which is a much larger expansion of a 2010 investigation, the researchers analyzed up to three blood samples for each individual with MS: the first taken when most of the military personnel were under the age of 20, the last taken years later, before the onset of the disease, and one in between. ![]() After infection, Epstein-Barr lives on in some B cells of the immune system and the antibodies developed to fight it remain in the blood. Everyone else is infected in adolescence and young adulthood, when Epstein-Barr usually leads to infectious mononucleosis, also called “kissing disease” because it is transmitted via saliva. Much of the world’s population, especially in developing countries, is infected with Epstein-Barr very early in life without much ill effect, although the virus can lead to several rare cancers. “When the original studies were done with cigarette smoking and lung cancer, they found a 25-fold risk factor for people who smoked more than 25 cigarettes a day,” Cohen says. Cohen, who heads the Laboratory of Infectious Diseases at the National Institute of Allergy and Infectious Diseases (NIAID) at the National Institutes of Health and was not involved in the research, is cautious about claiming “cause.” He argues that it still must be shown that preventing Epstein-Barr prevents MS but agrees the results are dramatic. It’s rare to get such black-and-white results.” Robinson and Lawrence Steinman, both at Stanford University, wrote, “These findings provide compelling data that implicate EBV as the trigger for the development of MS.” Epidemiologist Alberto Ascherio, senior author of the new study, says, “The bottom line is almost: if you’re not infected with EBV, you don’t get MS. In an accompanying commentary, immunologists William H. “These findings cannot be explained by any known risk factor for MS and suggest EBV as the leading cause of MS,” the researchers wrote. The results, published on September 13 in Science, show that the risk of multiple sclerosis increased 32-fold after infection with Epstein-Barr but not after infection with other viruses. The researchers were able to compare the outcomes of those who were subsequently infected and those who were not. About 5 percent of those individuals (several hundred thousand people) were negative for Epstein-Barr when they started military service, and 955 eventually developed MS. military (the samples were taken for routine HIV testing). Chan School of Public Health and Harvard Medical School turned to what they call “an experiment of nature.” They used two decades of blood samples from more than 10 million young adults on active duty in the U.S. A randomized trial to test such a hypothesis by purposely infecting thousands of people would of course be unethical. ![]() To prove that infection with Epstein-Barr causes MS, however, a research study would have to show that people would not develop the disease if they were not first infected with the virus. In the disease, inflammation damages the myelin sheath that insulates nerve cells, ultimately disrupting signals to and from the brain and causing a variety of symptoms, from numbness and pain to paralysis. But people who contract infectious mononucleosis are at slightly increased risk of developing MS. ![]() Unlike Epstein-Barr, MS, a devastating demyelinating disease of the central nervous system, is relatively rare. Epstein-Barr virus (EBV) is the primary cause of mononucleosis and is so common that 95 percent of adults carry it. A connection between the human herpesvirus Epstein-Barr and multiple sclerosis (MS) has long been suspected but has been difficult to prove.
0 Comments
Read More
Leave a Reply. |