Are vaccines an effective tool to prevent disease?

Vaccines are a well-studied prevention tool — I'll gather current evidence on how effectively they prevent disease.

Yes, vaccines are considered one of the most effective tools to prevent disease.

Scientific and public health consensus is that vaccines are effective at preventing serious infectious diseases:

•Vaccines are "one of the most effective tools for preventing serious diseases" according to decades of scientific research.

•Vaccines are the "safest and most effective way to prevent the spread of infectious diseases, including measles, whooping cough and polio."

•Getting vaccinated is described as "the most effective way to prevent infectious diseases" - it provides immunity against a range of infectious diseases and makes it harder for disease to spread.

How they work:

•A vaccine acts as a rehearsal for your immune system. By introducing a harmless component of a virus or bacteria, vaccines "teach" your immune system to recognize and fight off specific pathogens without you ever having to get sick. Once primed, the immune system can stop a disease from spreading before it causes harm.

•Vaccines can also reduce the severity and duration of a disease and are effective on an individual scale to help people avoid getting sick, while societies as a whole benefit.

Extent of protection:

•We now have vaccines to prevent more than 30 life-threatening diseases and infections, such as diphtheria, tetanus, pertussis, influenza and measles.

•Immunization currently prevents 3.5 million to 5 million deaths every year from diseases like diphtheria, tetanus, pertussis (whooping cough), influenza and measles.

•Vaccines have saved an estimated 154 million lives globally over 50 years, eliminated smallpox from the planet, and reduced diseases like polio and measles by over 99% in the United States.

•A CDC study of 117 million children born from 1994-2023 found that nine routine childhood vaccines prevented 508 million lifetime illnesses, 32 million hospitalizations and 1.13 million deaths. Vaccines prevented more than 500 million illnesses and 1.13 million deaths among children born over the last three decades.

Like all medical interventions, vaccines are not 100% effective in every individual and protection can wane over time requiring boosters, and high vaccination rates are needed to protect everyone in the community, especially children. Vaccines undergo rigorous testing before approval and continuous monitoring to ensure safety and effectiveness.

Overall, major health organizations including the World Health Organization (WHO), the U.S. Centers for Disease Control and Prevention (CDC), and the American Academy of Pediatrics (AAP) conclude that vaccines are safe, rigorously tested, and highly effective at preventing disease, reducing complications, hospitalizations and deaths, and preventing larger outbreaks.

Citations (3)

1aap.orgNonprofits and think tanks
Fact Checked: Immunizations Are Essential for Public Health and Child Safety
Backs: “Yes, vaccines are considered one of the most effective tools to prevent disease. Scientific and public health consensus is that vaccines are effective at preventing serious infectious diseases: Vaccines are "one of the most effective tools for preventing serious diseases" according to decades of scientific research.”
2who.intGovernment
Know the facts
Backs: “Vaccines can also reduce the severity and duration of a disease and are effective on an individual scale to help people avoid getting sick, while societies as a whole benefit.”
3aap.orgNonprofits and think tanks
Study: Childhood vaccines prevented 1.13 million deaths, saved $2.7 trillion over 3 decades
Backs: “Vaccines have saved an estimated 154 million lives globally over 50 years, eliminated smallpox from the planet, and reduced diseases like polio and measles by over 99% in the United States. A CDC study of 117 million children born from 1994-2023 found that nine routine childhood vaccines prevented 508 million lifetime…”