Multiple sclerosis is an autoimmune disease in humans that affects the myelin tissue, covering the nerve cells. The myelin sheath performs the protective function of nerve cells and contributes to signal transmission. Nerve cells receive sensory information and send signals to our muscles to take action. Multiple sclerosis causes scarring or sclerosis in the brainstem, cerebellum, optic nerve, and in many areas of the brain. It is caused by damage to the myelin sheath by immune cells. As a result, the body cannot perform its functions as it disrupts the signal transmission between nerve cells.
The signs and symptoms of MS vary widely and depend on the amount of nerve damage and the nerves affected. Some people with severe MS may lose the ability to walk independently, while others with mild illness may experience long periods of absence of illness without any new symptoms. Common symptoms are numbness or weakness in one or more limbs, lack of coordination or unsteady gait, partial or complete loss of vision usually in one eye at a time; slurred speech, difficulty concentrating or remembering, tiredness, dizziness, tingling or pain in parts of the body, electric shock sensations that occur with certain neck movements, problems with sexual function or passing stool and blood ‘urine.
The etiology of MS is still unclear. However, a person’s genetic predisposition and environmental conditions influence its onset. Treatment for this disorder includes medications, exercise, plasma exchange, immunoglobulins, occupational therapy, speech and swallowing therapy, and cognitive rehabilitation. There are many treatment options available, both by injection and by tablets, and patients should understand that treatment is long term and helps limit relapses and progression of the disease.
Vaccination guidelines for people with multiple sclerosis
Vaccines are biological products that elicit an immune response against pathogens and provide long-lasting protection. There are four types of vaccines: live attenuated vaccines (BCG, oral polio vaccine, measles, yellow fever), whole cell inactivated vaccines (hepatitis A, polio, typhoid, cholera), purified protein vaccines (toxoid) and genetically modified vaccines (hepatitis B vaccines, HPV).
These recommendations suggest that patients with MS should be screened for vaccine-preventable infections. In addition, the necessary vaccines should be given, including the annual influenza vaccine.
- All vaccines are generally considered safe for patients with MS who are not receiving any DMT (disease modifying therapies).
- Patients with MS receiving DMT should not receive live attenuated vaccine (LAV) such as BCG.
- Live attenuated vaccines can be given to patients with untreated MS.
- Attenuated vaccines do not cause relapse of MS and can therefore be given. This treatment is an exception for the vaccine against yellow fever because it is found that the vaccine against the 17D strain induces an exacerbation in patients with MS.
- Administration of vaccines with adjuvants is not encouraged as studies show that adjuvants such as aluminum salts have neurotoxic properties. People who relapse should delay vaccination until symptoms of relapse no longer worsen or resolve.
- Patients taking certain DMTs (Rituximab, Natalizumab, Mitoxantrone) will need to take their vaccines at specified intervals before or after their treatment.
- A complete vaccination history should be noted by the neurologist upon diagnosis of MS. In addition, booster injections should be given if necessary.
- Developing an EBV (Epstein-Barr virus) vaccine for use in infancy may reduce the risk of MS in the future.
-by RP Krishnan, Neurological Consultant, Fortis Hospital, Bannerghatta Road, Bangalore