Immunity is the body’s way of developing protection from viruses or other illnesses. Being immune can depend on certain factors like your nutritional status, genetics, level of stress, prior exposure to disease, or your vaccination status.
There are two types of immunity:
- Active immunity: Immunity that is produced when a person is exposed to a disease causing agent either from the environment or through a vaccine. This type of immunity is usually long lasting, if not permanent.
- Passive immunity: Immunity that is given to a person either through the placenta or breastmilk from a mother to a baby, or by injection like immunoglobulin.
Passive immunity received through the placenta does not typically last as long as active immunity, and may disappear within weeks to months.
When active immunity is not permanent, a booster may be required to ensure protection. This is why many vaccines require multiple doses and booster shots every couple of years. For example, the MMR vaccine is meant to provide immunity for a lifetime. However, immunity is not always achieved until they receive a booster, and for some, not at all.
Some parents choose to have their child’s “titers” checked before the booster is administered to determine immune status. A titer is a simple blood test that can let you and your doctor know if your child has enough antibodies against a disease (like measles or chickenpox) to be protected the next time they come in contact with that disease.
Boosters happen naturally as well. The first time a person has symptoms of chicken pox, they manifest as the classical childhood illness. Any time after that, they almost exclusively present as shingles. Before the vaccine for chicken pox was introduced, children who got the chicken pox actually acted as a natural booster for their parents and grandparents by stimulating their immune systems to ‘remember’ that virus. The fact that adults are no longer getting their natural boosters from young family members may be contributing to the increasing incidence of shingles in adults.
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The Focus for Health Foundation is dedicated to ensuring that every individual has access to the information necessary to make optimal health decisions for themselves and their families.
The mission of the Focus for Health Foundation (FFH) is to promote advocacy, education, and research to combat the rise of chronic illness occurring around the world. We support efforts that increase public awareness of the connection between hazardous environmental exposures and the immune system, and address how social determinants of health and inequality within populations creates vulnerability to disease.