Bale J F, Zimmerman B, Dawson J D, Souza I E, Petheram S J, Murph J R
Department of Pediatrics, University of Utah School of Medicine, Salt Lake City, USA.
Arch Pediatr Adolesc Med. 1999 Jan;153(1):75-9. doi: 10.1001/archpedi.153.1.75.
Children attending child care centers have high rates of cytomegalovirus (CMV) excretion. Women exposed to such children have an increased risk of acquiring CMV infection, and primary infection places the offspring of such women at risk of congenital CMV infection. We studied family child care homes to determine if this child care alternative might represent a safe haven from CMV.
One hundred thirty-two women providing care in their homes were studied using a latex agglutination method to determine the rate of CMV seropositivity at baseline. Women who were seronegative for CMV were then sampled prospectively at 6-month intervals between March 1991 and August 1994 to determine the annual rate of CMV acquisition. A point prevalence of CMV excretion in family homes was determined by sampling 106 children from 25 randomly selected homes. Cytomegalovirus isolates were compared by molecular analysis using polymerase chain reaction-based methods to identify transmission.
At baseline, 57.6% of the 132 providers were seropositive for CMV. Seropositive providers were more likely to be caring for toddlers (aged 1-2 years) (67% vs 46%; P=.02) and had worked in child care somewhat longer (median of 28.5 vs 21.5 months; P=.11). Using stepwise logistic regression, the strongest predictors of seropositivity at baseline were caring for children aged 1 to 2 years (odds ratio [OR] =2.37; P=.02) and number of months as a child care provider (OR= 1.17 for an increase of 24 months as provider; P=.08). Six or more years as a provider was highly associated with seropositivity (OR=3.27; P=.02). During follow-up, 5 of 51 seronegative providers seroconverted, yielding an annual infection rate of 6.8%. The point prevalence survey of children from the 25 homes (14 had seropositive providers) identified 8 CMV-excreting children. Three children in 1 home had indistinguishable isolates by polymerase chain reaction mapping. The provider seroconverted and excreted an isolate with a molecular profile indistinguishable from that of the children.
The prevalence of CMV excretion is low among children attending child care homes (8% vs 15% in prior studies of child care centers; P=.07), and only 1 (20%) in 5 of the homes had CMV-excreting children. However, the overall CMV seroconversion rate of home child care providers was comparable to the rate observed among providers in child care centers. Families who use family home child care as an alternative to large child care centers are exposed to a low and unpredictable risk of CMV infection.
在儿童保育中心的儿童巨细胞病毒（CMV）排泄率很高。接触这类儿童的女性感染CMV的风险增加，而初次感染会使这类女性的后代面临先天性CMV感染的风险。我们对家庭式儿童保育机构进行了研究，以确定这种儿童保育方式是否可能是一个远离CMV的安全场所。
对132名在家中提供保育服务的女性进行研究，使用乳胶凝集法确定基线时CMV血清阳性率。对CMV血清阴性的女性在1991年3月至1994年8月期间每隔6个月进行前瞻性采样，以确定CMV的年感染率。通过对25个随机选择家庭中的106名儿童进行采样，确定家庭中CMV排泄的点患病率。使用基于聚合酶链反应的方法通过分子分析比较CMV分离株以确定传播情况。
基线时，132名保育人员中有57.6%CMV血清阳性。血清阳性的保育人员更有可能照顾幼儿（1 - 2岁）（67%对46%；P = 0.02），并且从事儿童保育工作的时间稍长（中位数为28.5个月对21.5个月；P = 0.11）。使用逐步逻辑回归分析，基线时血清阳性的最强预测因素是照顾1至2岁的儿童（优势比[OR]=2.37；P = 0.02）以及作为儿童保育人员的月数（作为保育人员每增加24个月，OR = 1.17；P = 0.08）。作为保育人员6年或更长时间与血清阳性高度相关（OR = 3.27；P = 0.02）。在随访期间，51名血清阴性的保育人员中有5人血清转化，年感染率为6.8%。对25个家庭（14个家庭的保育人员血清阳性）的儿童进行的点患病率调查发现了8名排出CMV的儿童。1个家庭中的3名儿童通过聚合酶链反应图谱显示分离株无法区分。该家庭的保育人员血清转化并排出了一种分子特征与儿童无法区分的分离株。
在家庭式儿童保育机构中儿童CMV排泄的患病率较低（8%，而之前对儿童保育中心的研究为15%；P = 0.07），并且只有5个家庭中的1个（20%）有排出CMV的儿童。然而，家庭式儿童保育人员的总体CMV血清转化率与在儿童保育中心的保育人员中观察到的转化率相当。选择家庭式儿童保育而非大型儿童保育中心的家庭面临的CMV感染风险较低且不可预测。
