深圳市龙华区托幼及小学儿童水痘发病与疫苗接种现况

  目的  了解水痘疫苗预防接种政策实施后，深圳市龙华区水痘高发人群的疫苗接种及水痘流行现状，为指导当地制定水痘免疫规划措施提供参考。  方法  采用随机分层整群抽样方法，选择深圳市龙华区6个街道30所托幼机构及小学23 706名儿童进行电子问卷调查，对获得的年龄、年级、最近疫苗接种年份、接种剂次、发病情况、发病时疫苗接种情况等基础数据进行分析。  结果  龙华区托幼及小学儿童水痘疫苗总接种率为86.01%，其中1剂次接种率为55.61%，2剂次为30.41%。托幼机构及小学的接种率差异有统计学意义(χ2=154.95，P < 0.05)。各街道未接种率、1剂次接种率、2剂次接种率、总接种率差异均有统计学意义(χ2值分别为146.09，103.93，127.31，146.09，P值均 < 0.05)。年级别罹患率与年级的高低呈正比(χ_趋势2=8.65，P < 0.01)，托幼机构与小学的罹患率差异有统计学意义(χ2=478.69，P < 0.05)。各街道未接种罹患率、1剂次罹患率、总罹患率差异均有统计学意义(χ2值分别为54.49，74.59，151.49，P值均 < 0.05)。随间隔年份增加小学儿童罹患率具有线性趋势(χ_趋势2=24.28，P < 0.05)，1剂次水痘疫苗接种后间隔时间越长罹患率越高，2剂次疫苗可保证较长时间的保护效果。疫苗的保护率与年级的高低呈反比，各年级不同剂次疫苗保护率及效果指数之间的相关性有统计学意义(r值分别为0.80，0.63，P值均 < 0.05)。接种1剂次疫苗及2剂次疫苗效果最好的分别为小班、大班。  结论  龙华区政策实施后2剂次疫苗接种率明显提升，但未起到持久效果。建议将水痘疫苗纳入免疫规划，以达到保障易感人群目的。

aricella incidence and vaccination of children in kindergarten and primary school of Longhua District in Shenzhen

  Objective  To understand the situation of varicella prevalence and vaccination of susceptible population in Longhua District, and to provide reference for the varicella immunization program.  Methods  A total of 23 706 children from 30 childcare facilities and primary schools in 6 streets were randomly selected throughout the Longhua District. Date on age, grade, recent year and dosage of vaccination, varicella incidence, the overview of vaccination were collected and analyzed.  Results  The rate of vaccination in childcare facilities and primary schools was 86.01%, including 55.61% of 1 dose and 30.41% of 2 doses of vaccine. The differences of rate vaccination rate between the childcare facilities and primary schools had statistical significance(χ2=154.95, P < 0.05).Rate of no-vaccination, 1 dose vaccination and 2 doses vaccination across 6 streets differed significantly(χ2=146.09, 103.93, 127.31, 146.09, P < 0.05). There was an increasing positive association between grades and attack rate(χ2=8.65, P < 0.05). The differences of attack rate between the childcare facilities and primary schools was of statistical significance(χ2=478.69, P < 0.05). The differences of attack rate in street of no vaccination, 1 dose vaccination and total attack rate showed statistical significance(χ2=54.49, 74.59, 151.49, P < 0.05). There was an increasing linear trend of attack rate of primary school childrenby each year(χ2=24.28, P < 0.05). The attack rate increased with time after 1 dose vaccination, immune protection was obtuined for a longer period time after additional doses of vaccine.Negative association was found between grades and protective efficacy rate of varicella. The protective rate and efficacy index of different doses of vaccine in different grades were correlated(r=0.80, 0.63, P < 0.05). It was most effective after 1 dose vaccination among children in junior grade in kindergarten and 2 dose vaccination in senior grade.  Conclusion  After the implementation of vaccination program in Longhua District, the vaccination rate of 2 doses significantly increased, but not for a long time. Varicella vaccine should be included in immunization programme to protect vulnerable populations.