Claim that 79.4% of SIDS deaths occurred on same day as vaccination misinterprets CDC study

Key takeaway

Sudden infant death syndrome (SIDS) is described as the “sudden death of a baby younger than 1 year of age that doesn’t have a known cause”. SIDS risk factors identified by scientific studies include prone sleeping (sleeping on the stomach), smoking during pregnancy, and soft sleeping surfaces. Scientific evidence doesn’t support the claim of a causal relationship between SIDS and vaccination.

Reviewed content

Verdict:

Inaccurate

Claim:

“79.4% of babies who die of SIDS had a vaccine the same day”

Verdict detail

Factually inaccurate: The posts wrongly interpreted the study’s findings. The 79.4% figure cited referred to children who received more than one vaccine on the day of vaccination, not on the day of their death.
Misleading: If SIDS and childhood vaccination are causally linked, we would see a greater incidence of SIDS in vaccinated infants compared to unvaccinated infants. But published studies have found no increased incidence of SIDS in vaccinated infants relative to unvaccinated infants.

See our method of evaluation

Full Claim

“79.4% of babies who die of SIDS had a vaccine the same day”; “79.4% of babies who died from SIDS had a well visit that same day”

A slew of social media posts published early in December 2024 implied that sudden infant death syndrome (SIDS) was caused by vaccines. A similar claim was made by Jodie Meschuk, who describes herself as a “Autism-turnaround expert” and “Quantum Medicine specialist” on her website. Meschuk, who has more than 41,000 followers on Facebook, also falsely claimed that vaccines cause autism and promoted the unproven practice of drinking raw camel milk to reverse autism.

One example of such posts claimed that “79.4% of babies who die of SIDS had a vaccine the same day”. It referenced a study published in 2015 by researchers at the U.S. Centers for Disease Control and Prevention (CDC)^[1]. The 79.4% figure also appears in the other posts mentioned above.

SIDS is described as the “sudden death of a baby younger than 1 year of age that doesn’t have a known cause, even after a full investigation”. 90% of SIDS deaths occur before six months of age, with the number of these deaths peaking between one and four months of age.

SIDS is a common topic in vaccine misinformation, even though reputable studies haven’t found an association between SIDS and vaccines. In 2003, the U.S. Institute of Medicine (today the U.S. National Academy of Medicine) reviewed the evidence and concluded that “the evidence favors rejection of a causal relationship between exposure to multiple vaccines and SIDS”^[2]. Nevertheless, this baseless claim persists and some have sought to legitimize it using methodologically flawed studies, some of which Science Feedback addressed in previous reviews.

As with those earlier claims, the posts claiming that 79.4% of SIDS or child deaths are due to vaccination are incorrect and the result of misinterpreting the 2015 CDC study. We explain below.

No, study didn’t find 79.4% of SIDS cases occurred on same day as vaccination

The authors of the 2015 CDC study examined the U.S. Vaccine Adverse Event Reporting System (VAERS) for reports of deaths after vaccination between July 1997 and December 2013. They also examined medical records, autopsy reports, and death certificates to identify the cause of death. More than 2,100 reports were analyzed, with roughly 68% of the reports in children.

The study found that SIDS reports comprised about 28% of all death reports analyzed  (including adults) and “the most common vaccines temporally associated with deaths tended to be those typically recommended and given at the particular age”. The 79.4% figure appears in the study thrice, notably early on in the abstract (“For child death reports, 79.4% received >1 vaccine on the same day”).

In the study itself, the figure is reported with more detail (“Among the 1469 reports in children aged 0–17 years, 1166 (79.4%) received >1 vaccine on the day of vaccination”).

These additional details make it clear that the 79.4% figure referred to children who received more than one vaccine on the day of vaccination, not on the day of death.

From this, we might postulate that the social media posts’ understanding of the figure relied only on the briefer sentence in the abstract. And that brief sentence was misunderstood to mean that more than one vaccine was given on the “same day” that the death occurred. But as we pointed out earlier, an actual reading of the study shows this is incorrect.

A Reuters fact-check on similar claims from November 2021 also highlighted how this figure was misinterpreted. A CDC spokesperson clarified that this “meant that 79.4% of the babies who died had at some stage in their lives received more than one vaccination during a day visit to a clinic. They had received more than one vaccination on that one day. That was different from saying they had had the vaccination and died on the same day”.

Studies have found no association between SIDS and childhood vaccination

Claims that childhood vaccines cause SIDS commonly cite anecdotal accounts of unexplained infant deaths shortly after vaccination. While these stories may seem compelling, temporal associations alone are insufficient to demonstrate a causal relationship between the two.

One of the main reasons for this is because SIDS also occurs in unvaccinated infants. The peak of SIDS deaths in both vaccinated and unvaccinated children occurs around the age that infants receive vaccinations, meaning that SIDS occurring after vaccination can occur simply by chance^[3].

Thus, establishing causality requires more than temporal associations; we also need to determine whether SIDS is more frequent in vaccinated infants than in unvaccinated infants. If a causal association existed, we would expect to see a higher incidence of SIDS in vaccinated infants compared to unvaccinated infants.

But published studies on this subject didn’t find that vaccinated infants were more likely to have SIDS compared to unvaccinated infants^[4-7]. In fact, two found that SIDS was more likely to occur in unvaccinated infants compared to vaccinated infants^[6,7]. These findings contradict the claim that childhood vaccination increases the risk of SIDS.

In brief, scientific evidence shows that vaccination isn’t a risk factor for SIDS. On the contrary, SIDS risk factors identified by studies include prone sleeping (sleeping on the stomach), smoking during pregnancy, and soft sleeping surfaces^[8].

REFERENCES

• 1 – Moro et al. (2015) Deaths Reported to the Vaccine Adverse Event Reporting System, United States, 1997-2013. Clinical Infectious Diseases.
• 2 – Institute of Medicine (US) Immunization Safety Review Committee; Stratton K, Almario DA, Wizemann TM, et al., editors. Immunization Safety Review: Vaccinations and Sudden Unexpected Death in Infancy. Washington (DC): National Academies Press (US); 2003. Immunization Safety Review: Vaccinations and Sudden Unexpected Death in Infancy. Available from: https://www.ncbi.nlm.nih.gov/books/NBK221465/
• 3 –  Brotherton et al. (2005) Probability of coincident vaccination in the 24 or 48 hours preceding sudden infant death syndrome death in Australia. Pediatrics.
• 4 – Yang and Shaw. (2018) Sudden infant death syndrome, attention-deficit/hyperactivity disorder and vaccines: Longitudinal population analyses. Vaccine.
• 5 – Jonville-Béra et al. (2008) Sudden unexpected death in infants under 3 months of age and vaccination status – a case-control study. British Pharmaceutical Journal.
• 6 – Vennemann et al. (2007) Sudden infant death syndrome: No increased risk after immunisation. Vaccine.
• 7 – Fleming et al. (2001) The UK accelerated immunisation programme and sudden unexpected death in infancy: case-control study. BMJ.
• 8 – Moon et al. (2022) Sleep-Related Infant Deaths: Updated 2022 Recommendations for Reducing Infant Deaths in the Sleep Environment. Pediatrics.