Impacto de la vacuna neumocócica conjugada 13-valente en la incidencia de neumonía consolidante en menores de 5 años en el partido de Pilar, Buenos Aires: estudio de base poblacional

Abstract

Following the introduction of PCV13 in Argentina's immunization schedule, a fast and significant reduction in the incidence of CP was observed, mainly in infants younger than 1 year old in 2012 and in children younger than 2 years old in 2013.

Impact and Effectiveness of 10 and 13-Valent Pneumococcal Conjugate Vaccines on Hospitalization and Mortality in Children Aged Less than 5 Years in Latin American Countries: A Systematic Review

“…We observed higher VE when X-ray confirmed pneumonia was considered as opposed to clinical pneumonia, which considered generic clinical endpoints or diagnosis as coded by ICD-10 codes. Markedly high PCV-13 VE estimates were disclosed by two studies included in this review, in which bias and confounding had not been properly managed [18, 30]. This finding of our review is consistent with the literature where that specific end points and case definitions showed a more accurate VE on pneumonias due to pneumococcus.…”

“…Among those studies, 8 evaluated pneumonia hospitalizations only [17, 18, 21, 22, 25–28], 4 evaluated both hospitalized and outpatient pneumonia combined [24, 29–31] two evaluated both pneumonia hospitalizations and deaths [22, 24], and one evaluated only pneumonia deaths [23]. Among the 13 studies, there were 5 interrupted times series [21, 23–25, 32], 6 before-after [17, 27–30], 1 cohort [18] and 1 case-control study [22]. …”

“…But those study designs are inherently vulnerable to aggregation bias, and to confounding by epidemiological and health care setting changes concomitant to vaccination. Among ITS and before-after studies, two [28, 30] presented data on potential confounders. Five studies [21, 23, 25–27, 32] included other diseases without plausible association to PCV as a comparator, and in two of them estimates of effectiveness against a pneumococcal disease were “adjusted” for the change in the comparator.…”

“…Pre-vaccination periods ranged from 2 to 12 years (median: 4 years), although one study based its effectiveness assessment on rates of the year before PCV introduction [29]. Most studies [20, 21, 24, 25, 27, 30–32, 41, 42, 44, 45] considered a transition period (usually, the year of PCV introduction), which were excluded from analysis by some, or included either in pre-vaccination or post-vaccination by others.…”

“…Vaccination coverage was presented in ten studies [17, 19, 20, 24, 25, 27, 28, 30, 32, 44], for descriptive purposes only, except one [25] study in which discrepancies of effectiveness across cities were attributed to the proportion of vaccinated subjects.…”