I'll gather the latest evidence on how well vaccines prevent disease.
Yes, vaccines are an effective tool to prevent disease — this is supported by overwhelming scientific evidence and global health consensus.
•Vaccination is one of the most effective ways to prevent diseases
•Immunization is a global health success story, saving millions of lives every year. Vaccines reduce risks of getting a disease by working with your body's natural defenses to build protection. When you get a vaccine, your immune system responds
Scale of protection
•We now have vaccines to prevent more than 30 life-threatening diseases and infections
•Immunization currently prevents 3.5 million to 5 million deaths every year from diseases like diphtheria, tetanus, pertussis (whooping cough), influenza and measles
•Over the past 50 years, essential vaccines against just 14 diseases have saved at least 154 million lives
•Over the past 50 years, vaccines have saved more than 150 million lives, as ordinary people chose to protect themselves, their children and their communities from diseases like measles, diphtheria, pertussis, polio, and rotavirus
•The World Health Organization (WHO) estimates that 154 million lives have been saved by immunizations, that is an estimated 6 lives every minute of every year
•In the United States alone, Research shows that routine vaccinations for children born during 1994–2023 will have prevented about 508 million illnesses and 32 million hospitalizations and saved over 1.1 million lives
Historical evidence of effectiveness
•Vaccines have been a crucial tool in preventing and controlling infectious diseases for centuries
•The development and widespread use of vaccines have led to the eradication of smallpox and the near-elimination of diseases like polio and measles
•Nearly two centuries later, in 1980, the World Health Organization (WHO) declared smallpox eradicated worldwide. ... This was not achieved through a miracle cure or a breakthrough in medicine but through a vaccine administered systematically and in a coordinated manner on a global scale
•Through a global vaccination campaign led by the World Health Organization (WHO), smallpox became the first disease to be eradicated from the planet in 1980. This achievement serves as a testament to the effectiveness of vaccines in eliminating a highly contagious and deadly disease
•The introduction of a vaccine has, in many cases, led to a very large decrease in the incidence of the targeted disease — such as the 96% decrease in the incidence of polio that occurred within 7 years of the introduction of the Salk and Sabin polio vaccines
How effectiveness is measured
•Scientific evidence overwhelmingly supports the efficacy of vaccines in preventing the spread of infectious diseases and reducing the severity of illness
•Our results show that vaccines are effective in both limiting the spread of infection and containing a more severe course of disease in symptomatic patients
•COVID-19 vaccines approved by WHO are extremely effective in preventing death and severe disease
> Vaccines cannot always prevent infection, but they can substantially reduce the risk of serious disease
Effectiveness varies by vaccine, disease, and over time, and depends on high coverage to maintain community (herd) immunity, but the consensus among WHO, CDC, and peer-reviewed research is that vaccines are among the most cost-effective and proven public health interventions ever developed.