How effective are vaccines?

Hayden M. Pasco, MD
Family Medicine
Some people argue that there are very few deaths from vaccine-preventable diseases. However, globally, 1.5 million unvaccinated children under five years of age die each year from vaccine-preventable diseases. This is a much higher number than any of the risk factors for vaccine side effects, which occur at virtually undetectable rates. Unfortunately, while the United States has low rates of vaccine-preventable diseases, the global population does not fare as well. If the United States population begins to relax on vaccine standards, the risks for an outbreak of a dangerous disease increase, as these pathogens are just a plane ride away.
Julia Blank, M.D., a UCLA family medicine specialist, says that even some people who have received all of their vaccines may be at risk from exposure to unvaccinated disease carriers because most vaccines are not 100 percent effective. The measles vaccine, for example, has a 5 percent failure rate. Additionally, some children may be exposed before they are old enough to receive certain vaccines.
Dr. Michael Roizen, MD
Internal Medicine
Immunizations do not guarantee beyond a doubt that you won't get an illness. Although many immunizations ensure up to 90 percent resistance to a disease, flu shots, for example, are less reliable, offering only 45 to 80 percent benefit to predicted strains. Also, a person's resistance to disease often decreases as his or her RealAge (physiological age) increases, or if some other medical condition exists, meaning that an immunization may not be as effective. Nevertheless, when it comes to age-prevention, nothing is as quick and easy as keeping your immunizations current.
Dr. Mehmet Oz, MD
Cardiology (Cardiovascular Disease)
Vaccines prevent 20,500 infant deaths a year in the United States (compared to the prevaccine era) and innumerable other disorders such as brain dysfunction, paralysis, and even cancer in children and adults. Vaccines are credited with huge decreases in medical illnesses; the polio vaccine prevents polio and alone saves some $100 billion a year that would be spent in caring for polio victims, not to mention preventing suffering of the polio victims themselves. By reducing the prevalence of these infections in the population through vaccination, we can reduce the risk to those not able to be vaccinated or for whom vaccines may not work: to cite a few examples, those with immune deficiencies, those who are receiving treatments that hinder immunization, and those who are too young. If immunization rates were to decrease, the risk of infection would increase for all children, and especially for the most vulnerable members of society.

Continue Learning about Vaccines & Immunizations

Vaccines & Immunizations

Vaccines & Immunizations

Vaccines are commonly given to children in the form of a shot to help prevent serious diseases like measles and mumps. Vaccines are developed using either dead strains of a disease, weakened strains, or strains of a different dise...

ase. As adults, we receive flu vaccines or may need a booster of childhood vaccines to retain immunity. Travelers may receive vaccines either as a condition of entry to a country, or on recommendation of health officials. Generally there is little or no reaction to a vaccine, but in some cases the vaccine may cause an allergic reaction or a temporary, mild illness. Some vaccines are not safe for pregnant women, so it’s important to check with a healthcare professional.

Important: This content reflects information from various individuals and organizations and may offer alternative or opposing points of view. It should not be used for medical advice, diagnosis or treatment. As always, you should consult with your healthcare provider about your specific health needs.