Immunizations have been in the news a lot this year. It seems like everyone’s been interested in vaccines for one reason or another, from the measles outbreak and the seasonal flu to the Ebola virus. But while we talk a lot about these life-saving preventative medicines, only a few of us really know how they work and what sort of an impact they’ve had on us. In the spirit of Immunization Awareness Month, here’s some information on how vaccines work and why we all need them.
How Do Vaccines Work?
Vaccines were designed to get our body to do something it does naturally: recognize invaders, kill them off and store a memory for future infections. So if our body does this normally, why do we need vaccines? The body’s response to disease comes in two waves. When it’s first exposed, it takes time to recognize that there’s even a problem. Once that recognition happens, it also takes time to ramp up the attack. When the attack is eliminated, some of the cells that recognize the attacker get stored in the body so that the future attacks can be picked up and fought off more quickly.
Unfortunately, some people never get past this first stage. Their body doesn’t realize there’s an invader until it’s already too late. It might mount an attack, but the attack may be too feeble or unable to salvage a body that’s already shutting down. Vaccines are like a trial run that gets this first step done with. Pieces of an invader or a weak version of the invader that won’t cause illness are injected into the body. The body can attack these harmless versions of a more deadly attacker and hold that reaction in memory for the real thing.
What Other Things Come Along With Vaccines?
Much of the concern about vaccines has surrounded other components used in vaccines. There are two other main additives: adjuvants and preservatives. Adjuvants are a kind of chemical kick-start for the immune system. They help alert the immune system that an invader is present and get it to respond. Without these adjuvant chemicals, the body might never respond to the vaccine and a person might not be protected even if they were dosed with the inactivated invader.
Preservatives have also become an essential part of getting vaccines to everyone who needs them. Preservatives are chemicals that are used to stop bacteria from growing in the vaccine. If bacteria found their way into a vial and started to multiply, a person could be injected with a deadly pathogen on top of the harmless one in the vaccine. Without these preservatives, it would be impossible to vaccinate everyone who needs a shot because the vaccines would spoil too quickly and too easily.
Both adjuvants and preservatives that make it into vaccines are tested extensively to make sure they’re safe before they go into people. No studies have shown the chemicals used widely in today’s vaccines to be harmful to human health in the doses given in a typical vaccine.
What Impact Have Vaccines Had on Our Health?
Over the last 100 years, vaccines have helped reduce or eliminate disease in billions of people. Diseases like smallpox, polio, measles, whooping cough, diphtheria, and rubella used to kill millions of people at a time, and losing a child to disease was once a common experience among parents. These diseases have now become so rare that most people only know about them because of their scheduled immunizations. Vaccines have been one of the main reasons that life span has increased dramatically over the last 100 years and that the number of children dying early in life has dropped so dramatically. On top of that, many vaccines are under development that will address many more human diseases.
Why Don’t Vaccine-Preventable Diseases Disappear?
The success of vaccines is a fragile one. Many of these invaders can live in other animals as well as humans. They lie in wait for an unvaccinated person to appear and use them to jump into the human population. From there, they spread easily among people who aren’t protected. This is why we can’t just stop vaccinating against a disease once infections drop. The exceptions are diseases that infect only human beings, like smallpox. In those cases, once all infections are gone, no more virus exists and vaccination isn’t needed anymore.
Why Should I Get Vaccinated?
This is the biggest question I get from patients and friends. Vaccines have been and continue to be lifesaving. Chances are good that many of us wouldn’t be here if vaccines had never been discovered. But with infections from illnesses like measles so low, it can be easy to think we’re done with immunizations. Unfortunately, we can’t get rid of many pathogens for the reason I mentioned above, which means we’ll always be vulnerable without a vaccine.
On top of that, not everyone can get vaccinated. Babies and small children follow a schedule based on when their immune system is mature enough for a vaccine to take. Until they hit those ages, they’re vulnerable to diseases that unvaccinated adults might be carrying. Some diseases also depress or damage the immune system, making immunization impossible in those affected. Vaccinating most of the population protects the few who can’t be by forming a protective wall of immune people around them. This only works if enough people are vaccinated. If that number starts to dip, deadly invaders find their way into the population and wreak havoc on those without protection, which is what happened earlier this year with the measles outbreak.
Where Can I Get More Information?
Your doctor is a great place to start. She can directly address your questions and find resources for you if they don’t know all the answers. The Centers for Disease Control and Prevention, the National Institutes of Health, and the World Health Organization also have great resources.
Vaccines are one of the best tools we have for preventing disease. Talk to your doctor and make sure you and those you love are up to date and protected.