严重呼吸综合征患儿及密切接触者血清SARS相关冠状病毒抗体的检测分析

目的　了解严重急性呼吸综合征(severeacuterespiratorysyndrome ,SARS)患儿SARS相关冠状病毒(SARS CoV)特异性抗体水平和与SARS患儿密切接触的成人有无隐性感染。方法　采用间接免疫荧光(IFA)和ELISA两种方法检测北京市2 4例恢复期儿童SARS患者和2 6名与其密切接触的家长血清SARS CoV特异抗体,其中IFA法检测IgM和IgG抗体,ELISA检测IgM和混合抗体;同时通过入户问卷收集流行病学资料。结果　( 1 )IFA法测定血清SARS CoV IgG的阳性者1 0例( 4 2 % ) ,SARS CoV IgM阳性2例( 8% ) ;经ELISA法测定SARS CoV混合抗体的阳性者9例( 3 8% )。( 2 )流行病学资料显示抗体阳性的1 0例患儿中有明确SARS接触史的患儿8例,而在抗体阴性的1 3例中仅1例阳性(P <0 . 0 5)。( 3 ) 1位受检家长(患儿的祖母)IFA法检测SARS CoV IgG和ELISA法检测混合抗体均为阳性,约占4% ( 1 / 2 6) ,该患儿的祖父亦为SARS患者。结论　( 1 )有SARS接触史的患儿在抗体阳性组的比例较之在抗体阴性组的比例明显增高,提示流行病学史在儿科SARS临床诊断中具有重要价值。( 2 )未能证实与儿童SARS患者接触的成人中存在隐性感染。

Detection and analysis of specific antibodies against severe acute respiratory syndrome-associated coronavirus in serum from pediatric SARS patients and their paterfamilias

Objective To primarily examine the presence of serum specific antibodies against severe acute respiratory syndrome(SARS) associated coronavirus virus (SARS-CoV) in pediatric SARS patients and explore the possibility of subclinical infection in adults in close association with these pediatric cases. Methods Specific antibodies against SARS-CoV in serum specimens from 24 clinically confirmed pediatric SARS cases in convalescence and their 26 paterfamilias were assayed with two methods, including indirect immunnofluorescence assay (IFA) for detecting the antibodies of IgG and IgM and enzyme linked immunosorbent assay(ELISA) for IgM and mixed antibodies. General and epidemiological information about the subjects were collected using a standard questionnaire. Results (1) The positive rate of specific IgG and IgM detected by IFA were 42% and 8% ; the positive rates of mixed antibodies assayed with ELISA was 38%(9/24).(2) The ratio of patients having close contacts to SARS patients in cases with positive reaction was 8/10; wherase it was 1/13 among those with negative results(P<0.05). (3) The antibody of IgG detected by IFA and the mixed antibodies measured by ELISA emerged in one adult who had been in close contact with her infected husband and grandson. Conclusions (1) SARS-CoV infection was confirmed by serological method in 42% of 24 clinically diagnosed pediatric SARS,leading to the assumption that it is necessary to develop accurate and efficient way for screening for antigen or gene of SARS-CoV in diagnosis of pediatric SARS. (2) Epidemiological information has important value in diagnosis of pediatric SARS . (3) Our data don't confirm that there is subclinical SARS-CoV infection taking place through having close contacts with pediatric SARS cases.