Cited by 91Bacterial Infections and VaccinesVirology and Viral DiseasesInfectious Encephalopathies and Encephalitis

Encephalopathy After Whole-Cell Pertussis or Measles Vaccination: Lack of Evidence for a Causal Association in a Retrospective Case–Control Study

Ray, Paula, Hayward, Jean, Michelson, David, Lewis, Edwin, Schwalbe, Joan, Black, Steve, Shinefield, Henry, Marcy, Michael +5 more·2006·Pediatric Infectious Disease Journal

Abstract

BACKGROUND: Whole-cell pertussis (wP) and measles vaccines are effective in preventing disease but have also been suspected of increasing the risk of encephalopathy or encephalitis. Although many countries now use acellular pertussis vaccines, wP vaccine is still widely used in the developing world. It is therefore important to evaluate whether wP vaccine increases the risk of neurologic disorders. METHODS: A retrospective case-control study was performed at 4 health maintenance organizations. Records from January 1, 1981, through December 31, 1995, were examined to identify children aged 0 to 6 years old hospitalized with encephalopathy or related conditions. The cause of the encephalopathy was categorized as known, unknown or suspected but unconfirmed. Up to 3 controls were matched to each case. Conditional logistic regression was used to analyze the relative risk of encephalopathy after vaccination with diphtheria-tetanus-pertussis (DTP) or measles-mumps-rubella (MMR) vaccines in the 90 days before disease onset as defined by chart review compared with an equivalent period among controls indexed by matching on case onset date. RESULTS: Four-hundred fifty-two cases were identified. Cases were no more likely than controls to have received either vaccine during the 90 days before disease onset. When encephalopathies of known etiology were excluded, the odds ratio for case children having received DTP within 7 days before onset of disease was 1.22 (95% confidence interval [CI] = 0.45-3.31, P = 0.693) compared with control children. For MMR in the 90 days before onset of encephalopathy, the odds ratio was 1.23 (95% confidence interval = 0.51-2.98, P = 0.647). CONCLUSIONS: In this study of more than 2 million children, DTP and MMR vaccines were not associated with an increased risk of encephalopathy after vaccination.

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Crossref · 10.1097/01.inf.0000234067.84848.e1

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18 of 18 references verified0 citation errors · 0 not checkable

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  • In Ray 2006, the odds ratio for encephalopathy, Reyes syndrome or encephalitis at 7 to 14 days after MMR was 0.40 (95% CI 0.05 to 3.46).

    “OR 7 to 14 days 0.40 (95% CI from 0. 05 to 3.46)”

    From Vaccines for measles, mumps and rubella in children (2012) · cites this paper as Ray 2006

  • In Ray 2006, exposure to the MMR vaccine was not statistically different among cases and controls in any of the considered time intervals (7-14, 0-14, 0-30, 0-60, and 0-90 days).

    “In none of the considered time intervals was exposure to the MMR vaccine statistically different among the cases and controls.”

    From Vaccines for measles, mumps and rubella in children (2012) · cites this paper as Ray 2006

  • In Ray 2006, the odds ratio for encephalopathy, Reyes syndrome or encephalitis at 0 to 14 days after MMR was 0.35 (95% CI 0.04 to 2.95).

    “OR 0 to 14 days 0.35 (95% CI from 0. 04 to 2.95)”

    From Vaccines for measles, mumps and rubella in children (2012) · cites this paper as Ray 2006

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Authors
Ray, P., Hayward, J., Michelson, D., Lewis, E., Schwalbe, J., Black, S., Shinefield, H., Marcy, M., Huff, K., Ward, J., Mullooly, J., Chen, R., & Davis, R.
Affiliations
  • Kaiser Permanente (US)
  • Harbor–UCLA Medical Center (US)
  • Centers for Disease Control and Prevention (US)
Corresponding author
  • Ray, Paula
  • Hayward, Jean
  • Michelson, David
  • Lewis, Edwin
  • Schwalbe, Joan
  • Shinefield, Henry
Venue
Pediatric Infectious Disease Journal
Published
2006-09
Volume
25
Issue
9
Pages
768-773
ISSN
0891-3668 (ISSN-L)
OpenAlex
W2005334025
Cited by
91
References
18
Citations by year
2026: 2 · 2025: 3 · 2024: 2 · 2023: 2 · 2022: 2 · 2021: 7 · 2020: 5 · 2018: 3 · 2017: 5 · 2016: 5 · 2015: 6 · 2014: 5 · 2013: 9 · 2012: 5
FWCI
4.75
Type
journal article
Language
en
Open access
closed
Locations
  • The Pediatric Infectious Disease Journal (publishedVersion)
  • PubMed (publishedVersion)
Topics
  • Life Sciences › Immunology and Microbiology › Microbiology › Bacterial Infections and Vaccines
  • Health Sciences › Medicine › Epidemiology › Virology and Viral Diseases
  • Health Sciences › Medicine › Infectious Diseases › Infectious Encephalopathies and Encephalitis
Keywords
encephalopathy, whole-cell pertussis vaccine, measles vaccine, DTP vaccine, MMR vaccine, vaccine adverse events, encephalitis, acellular pertussis vaccine, children, vaccine safety
MeSH terms
Brain Diseases, Child, Child, Preschool, Encephalitis, Female, Humans, Infant, Infant, Newborn, Male, Retrospective Studies, Diphtheria-Tetanus-Pertussis Vaccine, Case-Control Studies, Measles-Mumps-Rubella Vaccine

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