
Viruses and MS
Viruses are tiny microbes that can make us ill. Some viruses might be involved in MS. One virus linked to MS is Epstein-Barr virus (EBV).
About viruses
Viruses are the smallest of all microbes. They enter a cell and hijack it to make copies of themselves. Then, the copies burst out of the cell to repeat the process. The infected cells usually break down.
The immune system is our main defence against viruses.
Some types of immune cells can produce antibodies, which stick to viruses. This stops viruses from entering new cells. And makes it easier for immune cells to surround and destroy the viruses.
Other types of immune cells can recognise those infected with the virus. These are programmed to destroy the infected cells.
After we’ve had an infection with a virus, our immune cells can remember it. So they’re ready to fight it again. This is also how vaccines work.
Some viral infections are quite minor and our bodies fight them off in a few days, like the common cold. But some are more harmful and difficult for our bodies to fight.
Viruses are hard to kill with drugs because they're mainly hiding inside the body’s cells. Antiviral treatments can catch viruses when they burst out of cells. But each antiviral only works against a specific virus. Antibiotics won’t affect viruses.
We supported a project showing EBV is linked to MS through T cells. The researchers took T cells from people with MS and people without MS, and grew the cells in a dish. They found T cells which responded to EBV also responded to myelin. This supports the idea the immune system is mistaking myelin for EBV. So, we better understand what’s happening in MS.
Now we’ve committed to raise funds for a new project focusing on EBV. The research will use blood samples to investigate whether EBV infects cells other than T cells and B cells.
Viruses other than EBV are linked to MS, though the link isn't as clear. And, they're less common than EBV.
- Epstein-Barr virus (EBV) is a very common type of herpes virus that has been linked to MS. Read more about EBV
- Human Herpes Virus 6 (HHV-6) is another type of herpes virus which may trigger MS. People with MS are more likely than people without MS to have had an infection with one version of the virus, HHV-6A. And, one study showed infection by HHV-6A more than doubled a person’s risk of developing MS.
- Cytomegalovirus (CMV) is another herpes virus. Some research shows that people who were infected with CMV had a reduced risk of developing MS. This might be because CMV interacts with other viruses, like EBV or HHV-6A. But we don’t fully understand how this works. There’s a vaccine against CMV in Phase III trials by a pharmaceutical company called Moderna.
- COVID-19 doesn’t increase your risk of getting MS. But some people with MS could be at greater risk of getting coronavirus, or of complications if they catch it.