Rotavirus infections, along with other febrile virus infections in childhood and adulthood, have long been linked to epilepsy in infants and children. A recently published study has shown that vaccination against rotavirus decreases seizures in children for at least the year following vaccination.
The risk of a seizure was decreased by 119 out of 100,000 person-years. Contrast this with a total increased risk of seizure after three pertussis immunizations of less than 32 out of 100,000. A series of 3 rotavirus immunizations was almost 4 times more effective at preventing seizures than a series of 3 pertussis immunizations was, perhaps, at inducing them.
Some parents may have been made cautious about allowing their children to be immunized, in general, against any infection, after media reports of seizures and brain disease following pertussis immunization. Now that we have a clear example of immunization protecting against seizures, will we see media hype about the benefit of vaccines?
That will probably not happen, of course. Don't hold your breath waiting for that outcome.
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Protective Association Between Rotavirus Vaccination and Childhood Seizures in the Year Following Vaccination in US Children
Daniel C. Payne1, James Baggs2, Danielle M. Zerr3,4, Nicola P. Klein5, Katherine Yih6, Jason Glanz7, Aaron T. Curns1, Eric Weintraub8, and Umesh D. Parashar1
+ Author Affiliations
1Epidemiology Branch, Division of Viral Diseases, National Center for Immunization and Respiratory Diseases 2Prevention and Response Branch, Division of Healthcare Quality Promotion, National Center for Zoonotic and Emerging Infectious Diseases, Centers for Disease Control and Prevention, Atlanta, Georgia 3Department of Pediatrics, University of Washington, Seattle 4Seattle Children's Research Institute, Washington 5Kaiser Permanente Vaccine Study Center, Kaiser Permanente, Oakland, California 6Department of Population Medicine, Harvard Medical School and Harvard Pilgrim Health Care Institute, Boston, Massachusetts 7Institute for Health Research, Kaiser Permanente Colorado, Denver 8Immunization Safety Office, Division of Healthcare Quality Promotion, National Center for Zoonotic and Emerging Infectious Diseases, Centers for Disease Control and Prevention, Atlanta, Georgia Correspondence: Daniel C. Payne, PhD, MSPH, Division of Viral Diseases, Epidemiology Branch, CDC, 1600 Clifton Rd NE, MS-A34, Atlanta, GA 30333 (dvp6@cdc.gov).
Abstract
Background. Rotavirus illness has been linked to childhood seizures. We investigated whether a protective association exists between receipt of rotavirus vaccine and being hospitalized or visiting the emergency department for seizures in the year after vaccination.
Methods. We retrospectively analyzed a cohort of children born after 28 February 2006 (when rotavirus vaccine was licensed in the United States) and enrolled in the Vaccine Safety Datalink (VSD) through November 2009. Seizure rates from 4 to 55 weeks following last rotavirus vaccination were compared by vaccine exposure status (fully vaccinated and unvaccinated). A time-to-event analysis using a Cox proportional hazards model was performed, accounting for time-varying covariates. We calculated the relative incidence of seizure compared by vaccine exposure status during the postexposure interval.
Results. Our cohort contained VSD data on 250 601 infants, including 186 502 children fully vaccinated (74.4%) and 64 099 (25.6%) not vaccinated with rotavirus vaccine. Rates of seizures were associated with rotavirus vaccination status. After adjusting for covariates (VSD site, age at last dose, sex, and calendar month of the index date), a statistically significant protective association was observed between a full course of rotavirus vaccination vs no vaccination for both first-ever seizures (risk ratio [RR] = 0.82; 95% confidence interval [CI], .73–.91) and all seizures (RR = 0.79; 95% CI, .71–.88).
Conclusions. A full course of rotavirus vaccination was statistically associated with an 18%–21% reduction in risk of seizure requiring hospitalization or emergency department care in the year following vaccination, compared with unvaccinated children. This reduction in childhood seizures complements the well-documented vaccine-related benefit of preventing US diarrhea hospitalizations.
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JAMA. 2012 Feb 22;307(8):823-31. doi: 10.1001/jama.2012.165.
Risk of febrile seizures and epilepsy after vaccination with diphtheria, tetanus, acellular pertussis, inactivated poliovirus, and Haemophilus influenzae type B.
Sun Y, Christensen J, Hviid A, Li J, Vedsted P, Olsen J, Vestergaard M.
Department of Public Health, Aarhus University, Bartholins Allé 2, DK-8000 Aarhus C, Denmark. ys@soci.au.dk
CONTEXT: Vaccination with whole-cell pertussis vaccine carries an increased risk of febrile seizures, but whether this risk applies to the acellular pertussis vaccine is not known. In Denmark, acellular pertussis vaccine has been included in the combined diphtheria-tetanus toxoids-acellular pertussis-inactivated poliovirus-Haemophilus influenzae type b (DTaP-IPV-Hib) vaccine since September 2002.
OBJECTIVE: To estimate the risk of febrile seizures and epilepsy after DTaP-IPV-Hib vaccination given at 3, 5, and 12 months.
DESIGN, SETTING, AND PARTICIPANTS: A population-based cohort study of 378,834 children who were born in Denmark between January 1, 2003, and December 31, 2008, and followed up through December 31, 2009; and a self-controlled case series (SCCS) study based on children with febrile seizures during follow-up of the cohort.
MAIN OUTCOME MEASURES: Hazard ratio (HR) of febrile seizures within 0 to 7 days (0, 1-3, and 4-7 days) after each vaccination and HR of epilepsy after first vaccination in the cohort study. Relative incidence of febrile seizures within 0 to 7 days (0, 1-3, and 4-7 days) after each vaccination in the SCCS study.
RESULTS: A total of 7811 children were diagnosed with febrile seizures before 18 months, of whom 17 were diagnosed within 0 to 7 days after the first (incidence rate, 0.8 per 100,000 person-days), 32 children after the second (1.3 per 100,000 person-days), and 201 children after the third (8.5 per 100,000 person-days) vaccinations. Overall, children did not have higher risks of febrile seizures during the 0 to 7 days after the 3 vaccinations vs a reference cohort of children who were not within 0 to 7 days of vaccination. However, a higher risk of febrile seizures was found on the day of the first (HR, 6.02; 95% CI, 2.86-12.65) and on the day of the second (HR, 3.94; 95% CI, 2.18-7.10), but not on the day of the third vaccination (HR, 1.07; 95% CI, 0.73-1.57) vs the reference cohort. On the day of vaccination, 9 children were diagnosed with febrile seizures after the first (5.5 per 100,000 person-days), 12 children after the second (5.7 per 100,000 person-days), and 27 children after the third (13.1 per 100,000 person-days) vaccinations. The relative incidences from the SCCS study design were similar to the cohort study design. Within 7 years of follow-up, 131 unvaccinated children and 2117 vaccinated children were diagnosed with epilepsy, 813 diagnosed between 3 and 15 months (2.4 per 1000 person-years) and 1304 diagnosed later in life (1.3 per 1000 person-years). After vaccination, children had a lower risk of epilepsy between 3 and 15 months (HR, 0.63; 95% CI, 0.50-0.79) and a similar risk for epilepsy later in life (HR, 1.01; 95% CI, 0.66-1.56) vs unvaccinated children.
CONCLUSIONS: DTaP-IPV-Hib vaccination was associated with an increased risk of febrile seizures on the day of the first 2 vaccinations given at 3 and 5 months, although the absolute risk was small. Vaccination with DTaP-IPV-Hib was not associated with an increased risk of epilepsy.
PMID: 22357833 [PubMed - indexed for MEDLINE]
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