目的 确定临床诊断为严重急性呼吸综合征(SAILS)患儿感染的病原是否为SAILS相关冠状病毒(SAILS-CoV);同时探讨儿童sARS患者的传播能力。方法2003年6-8月收集到的SAILS患者及其接触者血清标本177例,同时期的来源于非疫区择期手术儿童血清标本49例,以及无SAILS接触史的北京健康儿童血清标本93例,SAILS流行前儿童血清标本90例,总计409例。应用不同方法(包括酶联免疫吸附实验、间接免疫荧光、Western-blot等)、不同单位生产的试剂盒测定抗SAILS-CoV抗体。结果不同检测方法中,SAILS.CoV特异性IgG抗体阳性率在SAILS患儿中为39.1%-43.5%。成人SAILS患者中为57.1%-71.4%;与SAILS患儿接触的儿童中均为阴性。与SAILS患儿接触的成人中为6.0%-9.0%;与成人SAILS接触的儿童中为0-9.7%;与成人SAILS接触的成人中为4.4%-7.1%;同时期的正常儿童与非疫区择期手术儿童以及SAILS流行前的正常儿童血清标本用不同方法和试剂检测结果不尽相同。结论临床诊断为SAILS的患儿SAILS-CoV特异性IgG抗体阳性率(40%左右)明显低于临床诊断为SAILS的成人患者。提示在流行期间有相当一部分儿童sARS实际上是由其他的呼吸道病毒感染所致。与成人sARS接触的儿童和成人中,有一部分SAILS抗体为阳性,提示可能存在SAILS-CoV的隐性感染。目前已推广使用的SAILS诊断试剂对于儿童SAILS诊断的正确性还需要进一步的验证。
Objective To identify the etiologic agents from children who had been chnically diagnosed as severe acute respiratory syndrome (SAILS) during the epidemic in Beijing and to characterize the transmissibihty of SAILS from those children to others. Methods One hundred and seventy-seven serum specimens were collected during the period of June to August, 2003 from children and adults who had been clinically diagnosed as SAILS and who closely contacted with those diagnosed as SAILS during SAILS epidemic in Beijing. Serum specimens were also collected from 49 children from Anhui province which was non- epidemic region and 93 healthy kindergarten children without history of contacting with SAILS patients in Beijing during SAILS epidemic. Serum specimens collected from 90 healthy kindergarten children in Beijing in September 2002 were included in the study. All the 409 serum specimens were tested for specific antibodies against SAILS-associated coronavirus (SARS-CoV) by different methods including ELISA for specific IgM and IgG, whole antibodies against SARS-CoV, IFA for specific IgM and IgG against SARS- CoV, and Western-blot for IgG to expressed N protein from SARS-CoV. Results The positive rates of specific IgG and whole antibodies against SARS-CoV ranged from 39. 1% to 43.5% in the children who had been clinically diagnosed as SAILS,zero in children and 6. 0% to 9.0% in adults who had closely contacted with the clinically diagnosed SAILS children. Among those clinically diagnosed SAILS adult patients, the positive rates of specific IgG and whole antibodies against SARS-CoV were 57. 1% to 71.4%. In children and adults who closely contacted with these clinically diagnosed SARS adult patients, the positive rates of specific IgG and whole antibodies against SARS-CoV were 0 to 9. 7% and 4. 4% to 7. 1%, respectively. None of the serum specimens collected from healthy children before and during epidemic in Beijing and children from non-epidemic region was positive when IFA methods and ELISA with Beier kits were used