title: Intussusception risk and health benefits of rotavirus vaccination in Mexico and Brazil.
abstract: BACKGROUND
  Because postlicensure surveillance determined that a previous rotavirus vaccine, RotaShield, caused intussusception in 1 of every 10,000 recipients, we assessed the association of the new monovalent rotavirus vaccine (RV1) with intussusception after routine immunization of infants in Mexico and Brazil.
  
  
  METHODS
  We used case-series and case-control methods to assess the association between RV1 and intussusception. Infants with intussusception were identified through active surveillance at 69 hospitals (16 in Mexico and 53 in Brazil), and age-matched infants from the same neighborhood were enrolled as controls. Vaccination dates were verified by a review of vaccination cards or clinic records.
  
  
  RESULTS
  We enrolled 615 case patients (285 in Mexico and 330 in Brazil) and 2050 controls. An increased risk of intussusception 1 to 7 days after the first dose of RV1 was identified among infants in Mexico with the use of both the case-series method (incidence ratio, 5.3; 95% confidence interval [CI], 3.0 to 9.3) and the case-control method (odds ratio, 5.8; 95% CI, 2.6 to 13.0). No significant risk was found after the first dose among infants in Brazil, but an increased risk, albeit smaller than that seen after the first dose in Mexico--an increase by a factor of 1.9 to 2.6 - was seen 1 to 7 days after the second dose. A combined annual excess of 96 cases of intussusception in Mexico (approximately 1 per 51,000 infants) and in Brazil (approximately 1 per 68,000 infants) and of 5 deaths due to intussusception was attributable to RV1. However, RV1 prevented approximately 80,000 hospitalizations and 1300 deaths from diarrhea each year in these two countries.
  
  
  CONCLUSIONS
  RV1 was associated with a short-term risk of intussusception in approximately 1 of every 51,000 to 68,000 vaccinated infants. The absolute number of deaths and hospitalizations averted because of vaccination far exceeded the number of intussusception cases that may have been associated with vaccination. (Funded in part by the GAVI Alliance and the U.S. Department of Health and Human Services.).
authors.affiliation: Centers for Disease Control and Prevention, 1600 Clifton Rd., MS A-47, Atlanta, GA 30333, USA. mpatel@cdc.gov
authors.forename: Manish M
authors.initials: MM
authors.lastname: Patel
authors.forename: Vesta Richardson
authors.initials: VR
authors.lastname: López-Collada
authors.forename: Marília Mattos
authors.initials: MM
authors.lastname: Bulhões
authors.forename: Lucia Helena
authors.initials: LH
authors.lastname: De Oliveira
authors.forename: Aurora
authors.initials: A
authors.lastname: Bautista Márquez
authors.forename: Brendan
authors.initials: B
authors.lastname: Flannery
authors.forename: Marcelino
authors.initials: M
authors.lastname: Esparza-Aguilar
authors.forename: Ernesto Isaac
authors.initials: EI
authors.lastname: Montenegro Renoiner
authors.forename: María Edilia
authors.initials: ME
authors.lastname: Luna-Cruz
authors.forename: Helena Keico
authors.initials: HK
authors.lastname: Sato
authors.forename: Luz del Carmen
authors.initials: Ldel C
authors.lastname: Hernández-Hernández
authors.forename: Gerardo
authors.initials: G
authors.lastname: Toledo-Cortina
authors.forename: Magdalena
authors.initials: M
authors.lastname: Cerón-Rodríguez
authors.forename: Neydi
authors.initials: N
authors.lastname: Osnaya-Romero
authors.forename: Mario
authors.initials: M
authors.lastname: Martínez-Alcazar
authors.forename: Rocío Gabriela
authors.initials: RG
authors.lastname: Aguinaga-Villasenor
authors.forename: Arturo
authors.initials: A
authors.lastname: Plascencia-Hernández
authors.forename: Francisco
authors.initials: F
authors.lastname: Fojaco-González
authors.forename: Guillermo
authors.initials: G
authors.lastname: Hernández-Peredo Rezk
authors.forename: Sixto Fortino
authors.initials: SF
authors.lastname: Gutierrez-Ramírez
authors.forename: Roberto
authors.initials: R
authors.lastname: Dorame-Castillo
authors.forename: Rogelio
authors.initials: R
authors.lastname: Tinajero-Pizano
authors.forename: Bernice
authors.initials: B
authors.lastname: Mercado-Villegas
authors.forename: Marilia Reichelt
authors.initials: MR
authors.lastname: Barbosa
authors.forename: Eliane Mara Cesário
authors.initials: EM
authors.lastname: Maluf
authors.forename: Lucimar Bozza
authors.initials: LB
authors.lastname: Ferreira
authors.forename: Francisca Maria
authors.initials: FM
authors.lastname: de Carvalho
authors.forename: Ana Rosa
authors.initials: AR
authors.lastname: dos Santos
authors.forename: Eduardo Dolabella
authors.initials: ED
authors.lastname: Cesar
authors.forename: Maria Elisa Paula
authors.initials: ME
authors.lastname: de Oliveira
authors.forename: Carmem Lúcia Osterno
authors.initials: CL
authors.lastname: Silva
authors.forename: Maria
authors.initials: M
authors.lastname: de Los Angeles Cortes
authors.forename: Cuauhtemoc
authors.initials: C
authors.lastname: Ruiz Matus
authors.forename: Jacqueline
authors.initials: J
authors.lastname: Tate
authors.forename: Paul
authors.initials: P
authors.lastname: Gargiullo
authors.forename: Umesh D
authors.initials: UD
authors.lastname: Parashar
mesh_terms: D001938:Brazil / Q000453:epidemiology; D016022:Case-Control Studies; D005260:Female; D006760:Hospitalization / Q000706:statistics & numerical data; D006801:Humans; D015994:Incidence; D007223:Infant; D007231:Infant, Newborn; D007443:Intussusception / Q000453:epidemiology / Q000209:etiology* / Q000401:mortality; D016015:Logistic Models; D008297:Male; D008800:Mexico / Q000453:epidemiology; D012306:Risk; D012400:Rotavirus Infections / Q000517:prevention & control; D022243:Rotavirus Vaccines / Q000009:adverse effects*; D014613:Vaccines, Attenuated / Q000009:adverse effects
chemical_list: C492457:RIX4414 vaccine; D022243:Rotavirus Vaccines; D014613:Vaccines, Attenuated