With flu season affecting millions of people each year, ads for the flu shot are plastered on every possible media source every winter. These shots dramatically decrease a person’s chance of getting the flu, and yet over half of Americans did not get their flu shot in 2014-15, according to a study by the Centers for Disease Control and Prevention (CDC).

One reason why people may be opposed to vaccinations is because of unfounded myths that have spread in recent years. For instance, an unreliable study that has since been debunked from 1997 connected vaccinations with an increased rate of autism. Although this is false, the belief has scared many parents who, in turn, don’t vaccinate their children because they believe it will cause autism.

This can have many unintended consequences. Not only are unvaccinated children more susceptible to vaccine-preventable diseases themselves, but they also put those around them at risk to get these diseases. For example, after one unvaccinated teen brought the measles to New York City in 2013, 58 people in his community got the disease as well. This was the largest measles outbreak in NYC since 1992, and the city spent almost $395,000 to contain the outbreak, according to WebMD. Thus, it is vital that everyone receives key vaccines since being unvaccinated can unintentionally seriously affect others.

People may also refuse vaccinations for themselves or their children because they think vaccines are unnecessary since the infection rate is so low in America. In part, this is true. Diseases such as polio, diphtheria, and mumps have been nearly eradicated in the U.S. thanks, partially, to vaccines. If people stop getting vaccinated for these diseases, however, they can potentially reappear. This can occur if someone who is unvaccinated travels to a country where a certain disease is still present, as in the measles case mentioned above. Because of this, people must be vigilant in receiving vaccines on time and regularly. Cases for dangerous illnesses such as whooping cough have dramatically increased in recent years because of failure to do this, as reported by HealthLine.

Furthermore, many diseases that people receive vaccines for have not yet been cured. Refusing vaccination for these illnesses can have fatal consequences. In fact, about 40,000-50,000 adults in the U.S. die from vaccine-preventable diseases annually. It may seem as though skipping one flu shot will not cause any problems, but in some cases, it can have deadly repercussions.

All in all, vaccines have helped cure some of the most disastrous diseases in history, and continue to do so to this day. Without vaccinations, people would still suffer from debilitating illnesses such as tetanus, hepatitis B, and rubella. Those who don’t vaccinate, unfortunately, still run the risk of contracting these diseases. This is why it is so vital that everyone is vaccinated: so that society does not take a step backwards to a  time when devastating diseases ravaged entire communities.