不同时间间隔水痘疫苗应急接种有效性分析

Effectiveness of emergency vaccination with varicella vaccine at different time intervals after appearance of the first cases of varicella

目的分析首发水痘病例发病后不同时间间隔水痘疫苗应急接种的有效性,确定有效开展疫苗应急接种的时间。方法 2013年6月至2015年12月,将符合《上海市水痘疫苗应急接种实施方案》的上海市范围内幼托机构、小学、初中、高中、中等职业技术学校等集体机构中水痘疫苗接种的学生作为观察对象,在首发水痘病例发病后,不同时间间隔(0~3 d、4~7 d、8~14 d、15~21 d和22 d及以上)应急接种水痘疫苗,观察首发水痘病例发病后,不同时间间隔疫苗应急接种后水痘的继发情况。结果首发水痘病例发病后,间隔0~3 d开展应急接种组水痘续发率低于间隔4~7 d组,同时也低于间隔8~14和15~21 d组(P均<0.003);间隔4~7 d组低于间隔8~14和15~21 d组(P均<0.003);间隔8~14 d组高于15~21 d和22 d及以上组(P均<0.003)。首例水痘病例发病后间隔0~3 d开展应急接种组水痘罹患率低于间隔4~7 d、8~14 d、15~21 d和22 d及以上组(P均<0.003);间隔4~7 d组低于8~14 d、15~21 d和22 d及以上组(P均<0.003);间隔15~21 d组高于22 d及以上组(P<0.003)。结论在出现水痘疫情暴发后,最好在首例水痘病例发生后7 d内开展疫苗的应急接种,以有效降低水痘的续发率和罹患率。

Objective To analyze the effectiveness of emergency vaccination with varicella vaccine at different time intervals after occurrence of the first cases of varicella.Methods During the period of June 2013 to December 2015,the students from nursery,primary school,middle school,high schools and secondary vocational and technical school in Shanghai City,who met the requirements in Protocol for Emergency Varicella Vaccination in Shanghai City,were selected as the subjects,vaccinated with varicella vaccine at different time intervals（0-3 d,4-7 d,8-14 d,15-21 d and not less than 22 d）after occurrence of the first case of varicella,and observed for the secondary cases.Results The occurrence rate of secondary cases was higher in the subjects vaccinated at an interval of 0-3 d after the occurrence of the first case than in those at intervals of 4-7 d,8-14 d and 15-21 d（P〈0.003）,while in that at an interval of4-7 d than in those at 8-14 and 15-21 d（each P〈0.003）,and in that at 8-14 d than in those at 15-21 and not less than 22 d（each P〈0.003）.However,the attack rate of varicella was lower in the subjects with emergency inoculation at an interval of 0-3 d after occurrence of the first case than in those at 4-7,8-14,15-21 and not less than 22 d（each P〈0.003）,while in that at 4-7 d than in those at 8-14,15-21 and not less than 22 d（each P〈0.003,and in that at 15-21 d than in those at not less than 22 d（P〈0.003）.Conclusion When the varicella epidemic outbreaks,the emergency vaccination shall be carried out within 7 d after occurrence of the first case of varicella so as to effectively decrease the secondary occurrence rate and attack rate.