Effectiveness of 13-pneumococcal conjugate vaccine (PCV13) against invasive pneumococcal disease in children in the Dominican Republic

Abstract

BackgroundLimited data are available on the effectiveness of 13-valent pneumococcal conjugate vaccine (PCV13) in resource-poor settings and PCV naïve populations. The Dominican Republic introduced PCV13 in September 2013 using a 2 + 1 schedule (2, 4, and 12 months) without a catch-up campaign. We evaluated PCV13 effectiveness against vaccine-type (VT) invasive pneumococcal disease (IPD) among children in the Dominican Republic.MethodsWe conducted a matched case-control study. A case-patient was defined as VT-IPD identified by culture or polymerase chain reaction (PCR) from a normally sterile-site in a hospitalized child who was age-eligible to have received ≥1 PCV13 dose. Four age- and neighborhood-matched controls were enrolled for each case-patient. We collected demographic, vaccination history, and risk factor data. Conditional logistic regression was performed. Vaccine effectiveness was calculated as (1- adjusted matched odds ratio for vaccination) X 100%.ResultsWe enrolled 39 case-patients and 149 matched-controls. Most case-patients had pneumonia with pleural effusion (64%), followed by meningitis (28%) and septicemia (13%). The most common pneumococcal serotypes identified included 14 (18%), 3 (13%), 19A (10%), and 1 (8%). Fewer case-patients had ≥1 PCV13 dose as compared to controls (61.5% vs. 80.0%; p = 0.006). Adjusting for malnutrition and socioeconomic status, VE of ≥1 PCV13 dose compared to no doses was 67.2% (95% CI: 2.3% to 90.0%). Only 44% of controls were up-to-date for PCV13, suggesting low vaccine coverage in the population.ConclusionsWe found that PCV13 provided individual protection against VT-IPD in this resource-poor setting with a PCV-naïve population, despite low PCV13 coverage. Expanding vaccination coverage might increase PCV13 impact.

Impact of 13-Valent Pneumococcal Conjugate Vaccine on Nasopharyngeal Carriage Rates of Streptococcus pneumoniae in a Rural Community in the Dominican Republic

“…Despite its inclusion in the national immunization program 3 years prior to this study, PCV13 coverage was low in this rural study population, with 52% and 57% UTD for age at initial and follow-up visits, respectively. This is consistent with 2016 findings among an urban pediatric population in Santo Domingo, where 44% of hospitalized children age-eligible to have received ≥1 dose of PCV13 vaccine were UTD for age [ 12 ]. Series completion rates were also low: When restricting to children aged ≥12 months, only half of eligible subjects had received all 3 doses at either sample (40/80 [50%] at sample 1 and 48/95 [51%] at sample 2).…”

“…Community NP carriage rates have not previously been reported in the DR, and this is 1 of only 2 studies to examine pneumococcal serotype distribution after PCV13 introduction [ 12 ]. Despite its inclusion in the national immunization program 3 years prior to this study, PCV13 coverage was low in this rural study population, with 52% and 57% UTD for age at initial and follow-up visits, respectively.…”

“…In 1 pre-PCV13 study of IPD in hospitalized Dominican children, the most common serotypes identified were 14, 1, 3, and 6A/6B [ 11 ]. Post-PCV13, a case-control study of IPD in the same Dominican hospital most frequently identified serotypes 6A/6B, 14, 3, and 19A [ 12 ]. Similar serotype patterns both pre- and post-PCV13 introduction likely reflect the low vaccination coverage of PCV13 in this pediatric community.…”

“…A 2011 study by Feris-Iglesias et al in the DR described pre-PCV13 serotypes in hospitalized children (<18 years of age) with pneumonia and pleural effusion; results indicated that PCV13 would provide >90% coverage of cases if it was introduced [ 11 ]. From 2013–2016, at the same hospital in the DR, Tomczyk et al demonstrated PCV13 vaccine effectiveness for the prevention of invasive pneumococcal disease (IPD) of 67.2% among children age-eligible to have received ≥1 dose of PCV13 [ 12 ]; however, this study reported low (44%) coverage of the third booster dose of PCV13. A study in the US showed that toddlers are the main transmitters of pneumococci in the community [ 13 ], thus raising concerns about potential continued transmission of PCV13 serotypes by undervaccinated children in the DR.…”

Immunogenicity and safety of a 10-valent pneumococcal conjugate vaccine administered as a 2 + 1 schedule to healthy infants in The Gambia: a single-centre, double-blind, active-controlled, randomised, phase 3 trial

“…14 After at least one dose of PCV13, effectiveness against PCV13 vaccine-type invasive pneumococcal disease ranged from 66% (52-76) in children aged between 2 months and 9 years in the UK to 86% (62-95) in children aged 2-59 months in Canada. [15][16][17][18] Given the absence of consistent protection against serotype 3 generated by PCV13, effectiveness estimates consistently increase when invasive pneumococcal disease caused by this serotype is excluded. 16,18 After at least one dose of PHiD-CV, an effectiveness of 92% (58-100) against PHiD-CV vaccinetype invasive pneumococcal disease was reported in Finland.…”