Vaccinations 101: Everything You Need to Know

Dr. T. Jann Caison-Sorey

| 4 min read

Dr. T. Jann Caison-Sorey is a pediatrician, adolescent medicine physician...

Mature man receiving a vaccine from his doctor
During the first six years of life, children can receive up to 14 vaccines to prevent serious illnesses such as polio, tetanus and hepatitis B, among other vaccines. People of all ages need to be vaccinated to protect their personal health and the health of those around them.
How do vaccines work in the body?
Vaccines are created from a weakened or dead form of a specific virus or bacteria that causes a disease. Administered through an injection or nasal spray, the vaccine stimulates the immune system to produce antibodies by mimicking natural exposure and allowing the body to fight off the intended infection. For example, the influenza vaccine can contain a dead viral strain, a live viral strain or a non-viral strain and must be updated each year since the viruses that cause the flu constantly evolve.
How do vaccines protect people from illness?
There are several ways vaccines reduce the spread of infectious diseases:
  • Booster shots: After a person receives their first vaccine against an illness – whether as a child or an adult – booster shots may be used to increase their immunity by reintroducing the antigen into the system. Since every illness is different, some diseases may require a booster shot, while others do not. However, if a person has been exposed to a communicable disease (diseases that spread easily), they should contact a physician to explore the best treatment option.
  • Herd immunity: Herd immunity, also known as community immunity, is an indirect way of protecting vulnerable citizens. When most of a population is immunized, there are less viable carriers of disease. This makes it difficult for viruses and bacteria to spread from person-to-person. Vaccinated individuals are the last line of defense for those who opt-out of immunizations or have compromised immune systems.
  • Protecting children: Young children are vulnerable to infectious diseases because their immunity isn’t fully established. Initially, babies carry antibodies that are transferred from their mother during pregnancy. Over time, the effect wanes as the child begins to produce antibodies of their own.
  • Protecting seniors: Along with small children, seniors are also vulnerable to diseases. Older adults may have suppressed or weaker immune systems caused by previously contracted diseases and the ongoing use of certain medications. For example, seniors are more likely than most to have a flu-related risk for hospitalization or death.
How do I know if I need a vaccine?
The U.S. Centers for Disease Control and Prevention have established a routine vaccination schedule for children and adults that dictates when a person should receive vaccines in order to first establish and then maintain their immunity. Regularly scheduling annual appointments with a primary care provider can help individuals stay up to date on their vaccinations, which keep them healthy all year. Some vaccines, like for the seasonal flu, are administered annually, while others, such as tetanus, diphtheria and pertussis are recommended every 10 years as a booster shot. Additionally, individuals planning international trips should check government regulations for the recommendation or requirement of specific vaccines before traveling. For example, certain countries require travelers to show proof they have had a yellow fever vaccine. Those with health coverage typically have access to free routine vaccinations. Blue Cross Blue Shield of Michigan members can receive vaccinations through their primary care doctor or local pharmacy. Blue Care Network members can receive free treatment at participating locations.
The role of vaccines during the pandemic
As the COVID-19 pandemic strains health care resources in the fight against this new virus, individuals need to take every precaution to protect themselves from illness – including against older, more established diseases. Regularly receiving vaccines and booster shots builds up the general population’s herd immunity against established illnesses and will lessen the burden on hospitals as they tend to COVID-19 patients. While clinical trials are in development, there is no vaccine for COVID-19 at this time. Infectious diseases are constantly evolving, but so are effective medical treatments. The unpredictable nature of these illnesses is one of the many reasons why vaccines are a vital part of health care management and the first line of defense against biological threats, both seen and unseen. Dr. T. Jann Caison-Sorey, M.D., is a senior medical director with Senior Health Services, Emergent Holdings. Emergent Holdings is a separate entity contracted by Blue Cross Blue Shield of Michigan to perform administrative services for Blue Cross’ Medicare Advantage program. More from
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