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Misconceptions about Immunization

Misconception #4
Vaccines cause many harmful side effects, and even death --
and may cause long-term effects we don't even know about.

Vaccines are actually very safe, despite implications to the contrary in many anti-vaccine publications. These sometimes contain the number of reports received by the Vaccine Adverse Events Reporting System (VAERS) and suggest that all of them represent genuine vaccine side-effects. The mere number can be misleading because most vaccine adverse events are minor and temporary, such as a sore arm or mild fever. These can often be controlled by taking acetaminophen before or after vaccination. More serious adverse events occur rarely (on the order of one per thousands to one per millions of doses), and some are so rare that risk cannot be accurately assessed. As for vaccines causing death, again so few deaths can plausibly be attributed to vaccines that it is hard to assess the risk statistically. Of all deaths reported to VAERS between 1990 and 1992, only one is believed to be even possibly associated with a vaccine. Each death reported to VAERS is thoroughly examined to ensure that it is not related to a new vaccine-related problem, but little or no evidence suggests that vaccines have contributed to any of the reported deaths. The Institute of Medicine in its 1994 report states that the risk of death from vaccines is "extraordinarily low."

But looking at risk alone is not enough -- you must always look at both risks and benefits. Even one serious adverse effect in a million doses of vaccine cannot be justified if there is no benefit from the vaccination. If there were no vaccines, there would be many more cases of disease, and along with them, more serious side effects and more deaths. For example, according to an analysis of the benefit and risk of DTP immunization, if we had no immunization program in the United States, pertussis cases could increase 71-fold and deaths due to pertussis could increase 4-fold. Comparing the risk from disease with the risk from the vaccines can give us an idea of the benefits we get from vaccinating our children. The following table compares these risk for six diseases.

Disease-Related Risks Adverse Effects ofVaccination
Pneumonia: 1 in 20
Encephalitis: 1 in 2,000
Death: 1 in 3,000
Encephalitis: 1 in 300
Congenital Rubella Syndrome:
1 in 4, (if woman becomes infected
early in pregnancy)
MMR Vaccine
Encephalitis or severe allergic reaction:
1 in 1,000,000