Get PolitiFact in your inbox.
If Your Time is short
Sudden infant death syndrome refers to the sudden and unexplained death of an apparently healthy baby. Its causes are unknown, although there are recommended ways to reduce an infant’s risk factors.
SIDS cases that follow a vaccination can be reported to the U.S. Vaccine Adverse Event Reporting System, but VAERS data cannot be used alone to show causality.
Studies show that receiving recommended immunizations can lower an infant’s risk of SIDS.
A popular Instagram post falsely links vaccines to the deaths of babies, saying "Sudden Infant Death Syndrome (SIDS) is ABSOLUTELY a side effect of vaccination."
The image shows the word "vaccination" crossed out in red. The accompanying caption repeats the claim in other words, using a V-like symbol in place of the word "vaccine." Such tactics are often used to evade detection by fact-checkers.
SIDS refers to the sudden and unexplained death of an apparently healthy baby. In the U.S., there were around 1,250 infant deaths attributed to SIDS in 2019, according to the U.S. Centers for Disease Control and Prevention.
People who are skeptical of vaccines claim that common childhood immunizations are responsible for SIDS and other health conditions, but scientists and public health experts have found no causal connection between routinely recommended vaccines and SIDS.
There’s no known way to prevent SIDS (also called cot death or crib death), since its cause is unknown. However, many doctors and medical researchers believe that SIDS is associated with a buildup of carbon dioxide in the blood and low levels of oxygen. Other research suggests that brain abnormalities may make some babies more vulnerable to SIDS.
The Boston Children's Hospital advises that the risk of SIDS can be "vastly" reduced by avoiding smoking during pregnancy, putting infants to sleep on their backs and adapting their sleep environment.
SIDS cases are most common during infants’ second and third months. That’s also a time when babies are getting many recommended vaccinations, which has led some people to associate the two and prompted researchers to look into possible connections.
The U.S. Vaccine Adverse Event Reporting System, or VAERS, collects reports of adverse events, or suspected side effects, that occur after vaccination. It was developed as an early-warning system to help researchers detect patterns that may warrant further study.
One analysis of VAERS data looked at 1,244 deaths of children reported from 1997 to 2013, including 1,165 under age 1. There were 544 deaths attributed to SIDS where an autopsy report or death certificate was available, making it the most common cause of death. Among the children who died, those reports say, 79.4% received at least one vaccine on the same day.
But VAERS data on their own cannot be used to establish whether an adverse event such as death is caused by a vaccine. VAERS is an open system, so anyone can file a report, and they don’t need to prove that the event was caused by the vaccine. The CDC, which runs the site along with the U.S. Food and Drug Administration, warns that VAERS reports can be incomplete, inaccurate or unverified.
Infant deaths reported to VAERS have decreased since the 1990s, when the federal government and other groups launched "Back to Sleep," a national campaign to educate caregivers and parents about reducing the risk of SIDS.
In general, it is extremely rare for death to follow a vaccination. Vaccines are some of the most highly regulated and tested medical products used. And many studies and reviews have corroborated their safety.
Multiple research studies have concluded that no concerning patterns exist among VAERS-reported deaths that would point to vaccines as a cause.
An analysis of SIDS cases reported to VAERS concluded that associations between infant vaccination and SIDS is "coincidental and not causal."
The CDC recommends that during their first six months, infants receive immunization against diphtheria, tetanus, and whooping cough, polio, pneumococcal infections, rotavirus, Hepatitis B and Haemophilus influenzae type b, or Hib. Studies looking at each of these vaccines have found no associations between these vaccines and SIDS. (COVID-19 vaccines are currently not authorized for children under age 12.)
Research shows that immunizations are actually associated with a lower risk of SIDS.
"There is ample and consistent evidence that vaccination following the CDC guidelines reduces the risk of SIDS by about 50%," said Dr. Guohua Li, a professor of epidemiology and anesthesiology at Columbia University, citing an analysis of nine vaccine studies. The DPT vaccine against diphtheria, tetanus and whooping cough alone can reduce the risk of SIDS by 10%, and the risk of SIDS has also been inversely correlated with immunization against polio.
"In addition to providing vital protection against infectious diseases," Li said, "infant immunization coverage contributes significantly to reducing SIDS."
An Instagram post claimed that SIDS "is ABSOLUTELY a side effect of vaccination."
The causes of SIDS aren’t known.
Scientific studies and analyses have consistently shown that there is no causal relationship between vaccines and SIDS, and that receiving recommended immunizations can lower an infant’s risk of SIDS.
We rate this claim False.
Instagram Post, June 29
Email Interview, Dr. Robert Klitzman, Professor of Clinical Psychiatry and the founder and director of the Masters of Bioethics Program at Columbia University, July 1, 2021
Email Interview, Dr. Guohua Li, Professor of Epidemiology and Anesthesiology at Columbia University Mailman School of Public Health and Vagelos College of Physicians and Surgeons, July 1, 2021
PolitiFact, No, the FDA didn't hide information linking vaccine to autism, December 19, 2017
PolitiFact, There’s no proof that COVID-19 vaccine has injured or killed more than 900 children, May 26, 2021
FullFact, No evidence for drop in US sudden infant death syndrome cases, February 25, 2021
Centers for Disease Control and Prevention, SIDS
CDC, Sudden Infant Death Syndrome (SIDS) and Vaccines, August 14, 2020
Boston Children's Hospital, Sudden Infant Death Syndrome (SIDS) | Symptoms & Causes
Children’s Hospital of Philadelphia, Vaccines and Sudden Infant Death Syndrome (SIDS), January 7, 2019
Immunization Safety Office, Centers for Disease Control and Prevention, Deaths Reported to the Vaccine Adverse Event Reporting System, United States, 1997-2013, May 28, 2015
National Institutes of Health, Safe to Sleep
U.S. Department of Health and Human Services, VAERS
UK National Health Services, Sudden Infant Death Syndrome
British Journal of Clinical Pharmacology, Sudden unexpected death in infants under 3 months of age and vaccination status – a case-control study, July 7 2008
BMC Pediatrics, Association between sudden infant death syndrome and diphtheria-tetanus-pertussis immunisation: an ecological study, January 28, 2015
The Clinician’s Vaccine Safety Resource Guide, Do Vaccines Cause Sudden Infant Death Syndrome (SIDS)?, October 28, 2018
Fundamental & Clinical Pharmacology, Sudden infant death syndrome and diphtheria-tetanus-pertussis-poliomyelitis vaccination status, 1995
Health Feedback, No causal association between the DTaP vaccine and sudden infant death syndrome (SIDS), February 7, 2020
Pharmacoepidemiology & Drug Safety, The epidemiology of fatalities reported to the Vaccine Adverse Event Reporting System 1990–1997, October 25, 2001
Vaccine, Deaths following vaccination: What does the evidence show?, 2015
Read About Our Process
In a world of wild talk and fake news, help us stand up for the facts.