Impact of meningococcal C conjugate vaccination four years after introduction of routine childhood immunization in Brazil.
Routine infant immunization with meningococcal C conjugate (MCC) vaccination started in Brazil in November 2010, scheduled at three and five months plus a booster at 12-15months of age. No catch-up was implemented. We assessed the impact of vaccination on meningococcal C disease (MenC) four years after vaccination start in the National Immunization Program.



We performed an ecological quasi-experimental design from 2008 to 2014 using a deterministic linkage between the National Notification and the National Reference Laboratory databases for meningitis. We conducted an interrupted time-series analysis considering Brazil except for Salvador municipality, because an epidemic of serogroup C disease occurred in this city, which prompted a mass vaccination campaign with catch-up for adolescents in 2010. Observed MenC rates in the post-vaccination period were compared to expected rates calculated from the pre-vaccination years. Results for Salvador were presented as descriptive data. An additional time-series analysis was performed for the state of São Paulo.



A total of 18,136 MenC cases were analyzed. The highest incidence rates were observed for infants aged <12months and no second incident peak was observed for adolescents. For Brazil, MenC rates were reduced by 67.2% (95%CI 43.0-91.4%) for infants <12months of age, 92.0% (77.3-106.8%) for the age-group 12-23months, and 64.6% (24.6-104.5%) for children aged 2-4years. For children 5-9years old, MenC rates reduced 19.2% (9.5-28.9%). Overall, 955 MenC cases were averted in Brazil in individuals aged <40years after MCC vaccination. Results from São Paulo State, mirror the patterns seen in Brazil.



After four years of infants and toddlers vaccination start, MenC invasive disease reduced in the target population. This investigation provide a robust baseline to ascertain how much the upcoming catch-up dose in 12-13years of age will accelerate the decrease in MenC incidence rates among youths in Brazil.
Institute of Tropical Pathology and Public Health, Federal University of Goiás, Rua 235, s/n, Setor Universitário, Goiânia, Goiás CEP 74605-050, Brazil. Electronic address: alssandrade@gmail.com.
Ana Lucia
AL
Andrade
School of Nursing, Federal University of Goiás, Rua 227, s/n, Setor Leste Universitário, Goiânia, Goiás CEP 74605-080, Brazil.
Ruth
R
Minamisava
Institute of Tropical Pathology and Public Health, Federal University of Goiás, Rua 235, s/n, Setor Universitário, Goiânia, Goiás CEP 74605-050, Brazil.
Lisia Moura
LM
Tomich
Laboratory for Meningitis, Pneumonia and Pneumococcal Infection, Center of Bacteriology, Adolfo Lutz Institute, Secretary of Health of State of São Paulo, Avenida Dr. Arnaldo, 355, Cerqueira Cesar, São Paulo, São Paulo CEP 01246-902, Brazil.
Ana Paula
AP
Lemos
Laboratory for Meningitis, Pneumonia and Pneumococcal Infection, Center of Bacteriology, Adolfo Lutz Institute, Secretary of Health of State of São Paulo, Avenida Dr. Arnaldo, 355, Cerqueira Cesar, São Paulo, São Paulo CEP 01246-902, Brazil.
Maria Cecilia
MC
Gorla
Laboratory for Meningitis, Pneumonia and Pneumococcal Infection, Center of Bacteriology, Adolfo Lutz Institute, Secretary of Health of State of São Paulo, Avenida Dr. Arnaldo, 355, Cerqueira Cesar, São Paulo, São Paulo CEP 01246-902, Brazil.
Maria Cristina
MC
de Cunto Brandileone
National Immunization Program, Secretariat for Health Surveillance, Ministry of Health, Esplanada dos Ministérios, Bloco G, Brasília, Federal District CEP 70058-900, Brazil.
Carla Madga S
CMS
Domingues
National Immunization Program, Secretariat for Health Surveillance, Ministry of Health, Esplanada dos Ministérios, Bloco G, Brasília, Federal District CEP 70058-900, Brazil.
Camile
C
de Moraes
Institute of Tropical Pathology and Public Health, Federal University of Goiás, Rua 235, s/n, Setor Universitário, Goiânia, Goiás CEP 74605-050, Brazil.
Gabriela
G
Policena
Institute of Tropical Pathology and Public Health, Federal University of Goiás, Rua 235, s/n, Setor Universitário, Goiânia, Goiás CEP 74605-050, Brazil; Research and Education Institute (IEP), Hospital Sírio-Libanês, São Paulo, Brazil.
Ana Luiza
AL
Bierrenbach
D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001938:Brazil / Q000453:epidemiology; D002648:Child; D002675:Child, Preschool; D005260:Female; D006801:Humans; D015994:Incidence; D007223:Infant; D008297:Male; D008585:Meningitis, Meningococcal / Q000453:epidemiology* / Q000517:prevention & control*; D022401:Meningococcal Vaccines / Q000008:administration & dosage* / Q000276:immunology*; D008875:Middle Aged; D038542:Neisseria meningitidis, Serogroup C / Q000276:immunology* / Q000302:isolation & purification; D065228:Non-Randomized Controlled Trials as Topic; D055815:Young Adult
D022401:Meningococcal Vaccines
Data linkage; Interrupted time-series analysis; Invasive meningococcal disease; Meningococcal vaccines; Neisseria meningitidis; Serogroup C meningococcal disease; Surveillance; Vaccination impact