Jones Veronnie Faye, Harrison Christopher, Stout Gordon G, Hopkins Jennifer
Division of General Pediatrics, University of Louisville School of Medicine, 571 South Floyd Street, Louisville, KY 40202, USA.
Pediatr Infect Dis J. 2005 Nov;24(11):969-73. doi: 10.1097/01.inf.0000187030.83080.8a.
Universal infant heptavalent pneumococcal conjugate vaccine (PCV-7) immunization, dosed near to the originally recommended schedule of a 3-dose series in the first 6 months of life, then a booster between 12 and 15 months, should reduce nasopharyngeal (NP) carriage of Streptococcus pneumoniae (Spn) PCV-7 types. The reduced availability of PCV-7 altered immunization schedules, particularly for third and fourth PCV-7 doses. We evaluated NP colonization in relation to originally recommended intervals and numbers of PCV-7 doses.
Spn from NP cultures of a cohort of 106 normal children, obtained during 20 months of PCV-7 shortage, were identified and serotyped by standard methods.
Spn was detected in 153 of 418 cultures (37%). Age, >1 sibling, day-care attendance and prolonged PCV-7 dosing intervals were univariate risks for NP detection of PCV-7 types. PCV-7 strains comprised 7 of 15 (47%) of Spn before the first dose, 28 of 36 (78%) and 27 of 41 (66%), respectively, after the first and second dose and then 16 of 36 (44%) and 11 of 25 (44%) after the third and fourth doses. The risk of NP colonization with PCV-7 types was higher with intervals of >3 months between second and third doses and intervals of >8 months between the third and fourth doses. Multivariate analysis showed prolonged interval after the second and third PCV-7 doses and day-care attendance as risk factors for NP detection of PCV-7 strains.
Although PCV-7 serotypes were detected less after third and fourth PCV-7 doses, longer dosing intervals, particularly in day-care attendees, were associated with higher risk of PCV-7 detection in the NP.
通用型婴幼儿七价肺炎球菌结合疫苗（PCV-7）免疫接种，按照最初推荐的程序在出生后头6个月进行3剂次接种，然后在12至15个月时进行1剂次加强接种，应可减少肺炎链球菌（Spn）PCV-7血清型的鼻咽部（NP）携带。PCV-7供应减少改变了免疫程序，尤其是第三剂和第四剂PCV-7的接种。我们评估了与最初推荐的间隔时间和PCV-7接种剂次数相关的NP定植情况。
在PCV-7短缺的20个月期间，从106名正常儿童队列的NP培养物中获取Spn，采用标准方法进行鉴定和血清分型。
在418份培养物中的153份（37%）检测到Spn。年龄、有1个以上兄弟姐妹、参加日托以及PCV-7接种间隔延长是NP检测到PCV-7血清型的单因素风险因素。PCV-7菌株在第一剂接种前占Spn的15株中的7株（47%），在第一剂和第二剂接种后分别占36株中的28株（78%）和41株中的27株（66%），然后在第三剂和第四剂接种后分别占36株中的16株（44%）和25株中的11株（44%）。第二剂和第三剂之间间隔>3个月以及第三剂和第四剂之间间隔>8个月时，NP被PCV-7血清型定植的风险更高。多因素分析显示，第二剂和第三剂PCV-7接种后间隔延长以及参加日托是NP检测到PCV-7菌株的风险因素。
虽然在第三剂和第四剂PCV-7接种后检测到的PCV-7血清型较少，但较长的接种间隔，尤其是在日托儿童中，与NP中检测到PCV-7的较高风险相关。
