Invasive disease potential of Streptococcus pneumoniae serotypes before and after 10-valent pneumococcal conjugate vaccine introduction in a rural area, southern Mozambique.
Sérgio Massora, Fernanda C Lessa, Benild Moiane, Fabiana C Pimenta, Hélio Mucavele, Alberto Chaúque, Anélsio Cossa, Jennifer R Verani, Nelson Tembe, Maria da Gloria Carvalho, Carmen Muñoz-Almagro, Betuel Sigaúque
Author Information
Sérgio Massora: Fundação Manhiça, Centro de Investigação em Saúde da Manhiça (CISM), Maputo, Mozambique. Electronic address: sergio.massora@manhica.net.
Fernanda C Lessa: Respiratory Diseases Branch, Centers for Disease Control and Prevention, Atlanta, Georgia, United States of America. Electronic address: dta3@cdc.gov.
Benild Moiane: Fundação Manhiça, Centro de Investigação em Saúde da Manhiça (CISM), Maputo, Mozambique. Electronic address: benild.moiane@manhica.net.
Fabiana C Pimenta: Respiratory Diseases Branch, Centers for Disease Control and Prevention, Atlanta, Georgia, United States of America. Electronic address: gzy7@cdc.gov.
Hélio Mucavele: Fundação Manhiça, Centro de Investigação em Saúde da Manhiça (CISM), Maputo, Mozambique. Electronic address: helio.mucavele@manhica.net.
Alberto Chaúque: Fundação Manhiça, Centro de Investigação em Saúde da Manhiça (CISM), Maputo, Mozambique. Electronic address: alberto.chauque@mahica.net.
Anélsio Cossa: Fundação Manhiça, Centro de Investigação em Saúde da Manhiça (CISM), Maputo, Mozambique. Electronic address: anelsio.cossa@manhica.net.
Jennifer R Verani: Respiratory Diseases Branch, Centers for Disease Control and Prevention, Atlanta, Georgia, United States of America. Electronic address: qzr7@cdc.gov.
Nelson Tembe: Fundação Manhiça, Centro de Investigação em Saúde da Manhiça (CISM), Maputo, Mozambique. Electronic address: nelson.tembe@manhica.net.
Maria da Gloria Carvalho: Respiratory Diseases Branch, Centers for Disease Control and Prevention, Atlanta, Georgia, United States of America. Electronic address: msc8@cdc.gov.
Carmen Muñoz-Almagro: Molecular Microbiology Department, Instituto de Recerca Pediatrica, University Hospital Sant Joan de Deu, Barcelona, Spain; Ciber of Epidemiology and Public Health, CIBERESP, Instituto de Salud Carlos III, Madrid, Spain; Medicine Department, Universitat Internacional de Catalunya, Barcelona, Spain. Electronic address: cma@sjdhospitalbarcelona.org.
Betuel Sigaúque: Fundação Manhiça, Centro de Investigação em Saúde da Manhiça (CISM), Maputo, Mozambique. Electronic address: betuel.sigauque@manhica.net.
BACKGROUND: Invasive pneumococcal disease (IPD) is a significant cause of morbidity and mortality among children worldwide. In April 2013, Mozambique introduced 10-valent PCV (PCV10) into the National Expanded Program on immunization using a three-dose schedule at 2, 3, and 4 months of age. We aimed to evaluate the invasive disease potential of pneumococcal serotypes among children in our region before and after PCV10 introduction. METHODS: We used data from ongoing population-based surveillance for IPD and cross-sectional pneumococcal carriage surveys among children aged <5 years in Manhiҫa, Mozambique. To determine the invasive disease potential for each serotype pre- and post-PCV10 introduction, odds ratios (OR) and 95% confidence intervals (95% CI) were calculated comparing serotype-specific prevalence in IPD and in carriage. For each serotype, OR and 95% CI > 1 indicated high invasive disease potential and OR and 95% CI < 1 indicated low invasive disease potential. RESULTS: In the pre-PCV10 period, 524 pneumococcal isolates were obtained from 411 colonized children and IPD cases were detected in 40 children. In the post-PCV10 period, 540 pneumococcal isolates were obtained from 507 colonized children and IPD cases were detected in 30 children. The most prevalent serotypes causing IPD pre-PCV10 were 6A (17.5%), 6B (15.0%), 14 (12.5%), 23F (10.0%) and 19F (7.5%), and post-PCV10 were 6A (36.7%), 13 (10%), 1 (10.0%), 6B (6.7%) and 19A (6.7%). Serotypes associated with high invasive disease potential pre-PCV10 included 1 (OR:22.3 [95% CI 2.0; 251.2]), 6B (OR:3.1 [95% CI 1.2; 8.1]), 14 (OR: 3.4 [95% CI 1.2; 9.8]) and post-PCV10 included serotype 6A (OR:6.1[95% CI 2.7; 13.5]). CONCLUSION: The number of serotypes with high invasive disease potential decreased after PCV10 introduction. Serotype 6A, which is not included in PCV10, was the most common cause of IPD throughout the study and showed a high invasive potential in the post-PCV10 period.
