The Faculty of Health Sciences, Ben-Gurion University of the Negev, Beer-Sheva, Israel; The Pediatric Infectious Disease Unit, Soroka University Medical Center, Beer-Sheva, Israel.
The Faculty of Health Sciences, Ben-Gurion University of the Negev, Beer-Sheva, Israel.
Vaccine. 2022 Jan 28;40(4):568-573. doi: 10.1016/j.vaccine.2021.12.025. Epub 2021 Dec 29.
Preterm-born children are prone to respiratory infections and complications during infancy and early childhood. In Israel, pneumococcal conjugated vaccines (PCVs) were introduced in 2009-2010, with high vaccination coverage. We assessed the impact of PCV implementation on community-acquired alveolar pneumonia (CAAP) in children < 2 years old born prematurely, in comparison with term born infants.
We conducted a prospective, active, population-based surveillance of children < 2 years old with radiologically-proven CAAP, visiting the only regional medical center. CAAP incidence in the pre-PCV and post-PCV eras were compared in early premature (29-32 weeks gestational age [WGA]), late premature (33-36 WGA) and term-born infants (>36 WGA).
Of 214,947 births during the study period, 6'791 CAAP episodes were diagnosed; 211, 653 and 5,806 were in early premature, late premature and term infants, respectively. After PCV implementation, overall CAAP visits were reduced by 44% (95% CI 36-51): 60%, 21% and 45% among those born early preterm, late preterm and at term, respectively (statistically significant for children born early preterm and at term). For outpatients, the respective rate reductions were 79%, 40% and 65% (statistically significant for the children born at term). Importantly, the mean annual rates in the post-PCV period became similar in all 3 groups. The rate reductions among the hospitalized children were lower those that among the non-hospitalized children, with reductions of 56%, 16% and 33% for the three groups, respectively (statistically significant for early preterm and at term children).
CAAP reduction trends after PCV implementation for preterm-born infants were similar to those for term-born infants. Whether this was because of similar direct PCV- protection, because of indirect (herd) protection or both, is unclear. Post-PCV implementation, the gaps in CAAP rates between infants born prematurely and at term were reduced.
早产儿在婴儿期和幼儿期易患呼吸道感染和并发症。在以色列，肺炎球菌结合疫苗（PCV）于 2009-2010 年推出，接种率很高。我们评估了 PCV 实施对<2 岁早产儿社区获得性肺泡肺炎（CAAP）的影响，与足月出生的婴儿进行比较。
我们对<2 岁经放射学证实的 CAAP 患儿进行了前瞻性、主动、基于人群的监测，访问了唯一的区域医疗中心。比较了 PCV 实施前后早早产儿（29-32 周胎龄[WGA]）、晚早产儿（33-36 WGA）和足月出生婴儿（>36 WGA）的 CAAP 发生率。
在研究期间，有 214947 例出生，诊断出 6791 例 CAAP 发作；分别有 211、653 和 5806 例早早产儿、晚早产儿和足月出生婴儿发生 CAAP。PCV 实施后，整体 CAAP 就诊率下降了 44%（95%CI 36-51%）：分别出生的早早产儿、晚早产儿和足月出生婴儿的下降率分别为 60%、21%和 45%（早早产儿和足月出生婴儿的下降率有统计学意义）。对于门诊患者，相应的降幅分别为 79%、40%和 65%（足月出生婴儿的降幅有统计学意义）。重要的是，PCV 实施后，所有 3 组的平均年发生率变得相似。住院患儿的降幅低于非住院患儿，分别为早早产儿和足月出生婴儿的下降率分别为 56%、16%和 33%（早早产儿和足月出生婴儿的降幅有统计学意义）。
PCV 实施后，早产儿 CAAP 下降趋势与足月出生婴儿相似。这是由于直接的 PCV 保护，还是由于间接（群体）保护，或者两者兼而有之，尚不清楚。PCV 实施后，早产儿和足月出生婴儿之间 CAAP 发生率的差距缩小。
