Anti-SARS-CoV immunoglobulin G in healthcare workers, Guangzhou, China

To determine the prevalence of inapparent infection with severe acute respiratory syndrome (SARS) among healthcare workers, we performed a serosurvey to test for immunoglobulin (Ig) G antibodies to the SARS coronavirus (SARS-CoV) among 1,147 healthcare workers in 3 hospitals that admitted SARS patients in mid-May 2003. Among them were 90 healthcare workers with SARS. As a reference group, 709 healthcare workers who worked in 2 hospitals that never admitted any SARS patients were similarly tested. The seroprevalence rate was 88.9% (80/90) for healthcare workers with SARS and 1.4% (15/1,057) for healthcare workers who were apparently healthy. The seroprevalence in the reference group was 0.4% (3/709). These findings suggest that inapparent infection is uncommon. Low level of immunity among unaffected healthcare workers reinforces the need for adequate personal protection and other infection control measures in hospitals to prevent future epidemics.     

广州市2003年冬季传染性非典型肺炎流行病学分析

目的分析传染性非典型肺炎(下称SARS)的流行特点,探讨SARS感染发病的特征,为制定SARS防制策略提供依据。方法用现场流行病学与血清流行病学调查方法,分析广州市2003年冬季SARS流行特征。结果广州市2003年12月16日至2004年1月7日共报告SARS病例4例,男性3例,女性1例,年龄20~40岁;患者病情较轻,无ARDS和死亡;3例患者在发病后5~6d就可检测出SARS-CoVIgG、IgM抗体;均属本地社区感染病例,其中3例患者与经营果子狸的T、S餐厅有流行病学联系,但病例间无直接的流行病传播关系。257名接触者无一例发病;T及S餐厅129名员工中血清SARS-CoVIgG阳性率为6.20%(8/129),8例SARS-CoVIgG阳性者中1例为报告病例,1例为近期感染轻型病例,1例为2003年初可疑SARS病例,5例为隐性感染者;两餐厅员工的SARS-CoVIgG阳性率明显高于健康对照人群(0.43%)和服务业从业人员(0.29%);T酒家存栏的6只果子狸咽拭子均检出SARS-CoVRNA。结论广州2003年冬季SARS流行强度低、病例病情轻,未显示出有传染性,存在有隐性感染者和轻型病例,SARS-CoV来源与动物(果子狸)密切相关。     

SARS-associated coronavirus transmission, United States

To better assess the risk for transmission of the severe acute respiratory syndrome-associated coronavirus (SARS-CoV), we obtained serial specimens and clinical and exposure data from seven confirmed U.S. SARS patients and their 10 household contacts. SARS-CoV was detected in a day-14 sputum specimen from one case-patient and in five stool specimens from two case-patients. In one case-patient, SARS-CoV persisted in stool for at least 26 days after symptom onset. The highest amounts of virus were in the day-14 sputum sample and a day-14 stool sample. Residual respiratory symptoms were still present in recovered SARS case-patients 2 months after illness onset. Possible transmission of SARS-CoV occurred in one household contact, but this person had also traveled to a SARS-affected area. The data suggest that SARS-CoV is not always transmitted efficiently. Routine collection and testing of stool and sputum specimens of probable SARS case-patients may help the early detection of SARS-CoV infection.     

我市医务人员严重急性呼吸综合征医院感染流行原因调查与对策

目的 调查某市医务人员感染严重急性呼吸综合征(severe acute respiratory syndrome，SARS)的途径及危险因素。方法 对直接参加过抢救和间接接触SARS患而被感染的医务人员采取统一填表、座谈、走访、电话采访等方式进行调查。结果 调查三所医院感染SARS的医务人员共88人，占全市发病医务人员总人数的87．13％。导致医务人员易感的原因是：对疾病缺乏认识，防范意识不强；管理网络不健全；患隐瞒流行病史；隔离环境及防护用品达不到要求等。结论 重视医院感染管理及对医务人员的医院感染知识培训，强化消毒隔离和自我保护意识，是控制医院感染流行及保护医务人员的有力措施。     

Severe acute respiratory syndrome: lessons from Singapore

An outbreak of severe acute respiratory syndrome (SARS) occurred in Singapore in March 2003. To illustrate the problems in diagnosing and containing SARS in the hospital, we describe a case series and highlight changes in triage and infection control practices that resulted. By implementing these changes, we have stopped the nosocomial transmission of the virus.An outbreak of severe acute respiratory syndrome (SARS) was first recognized in Singapore on March 12, 2003. The index patient was hospitalized at Tan Tock Seng Hospital, which has since become the country’s designated SARS hospital. The patient infected 20 other people (including patients and healthcare workers), who subsequently became the sources for secondary spread of the infection (1). As of June 12, 2003, a total of 206 cases and 31 deaths attributed to SARS had been reported in Singapore.We describe the important lessons learned during the triage and containment of SARS at the National University Hospital, Singapore. Both involved expanding isolation criteria to include all patients with undifferentiated fever (even in the absence of respiratory symptoms or chest x-ray changes), improving contact-tracing methods, enforcing the use of fit-tested personal protective equipment in all patient-care areas, avoiding aerosol-generating procedures, and carefully monitoring all healthcare workers for fever or respiratory symptoms. We also highlight the impact of these measures on preventing the entry and nosocomial spread of infection.     

SARS流行时期医务人员防护及效果评价

目的了解广东省有急性传染性非典型肺炎(SARS)接触史的医务人员在防治SARS时期的个人防护状况,评价防护措施对预防SARS感染的效果. 方法对广东省9所诊治SARS的医院中所有有SARS接触史的工作人员进行调查. 结果1 645名调查对象中有 152例感染SARS,其中有79.61%的确诊时间在2003年2月,随时间推移而确诊病例数迅速减少;同时,所有调查对象在第1次接触SARS时对各项防护工具的使用率随时间推移而增加,趋势检验均有统计学意义;第1次接触SARS时使用各项防护工具的医务人员感染SARS的频率均低于没有使用者;9所医院医务人员对防护工具使用率和感染率也呈负相关关系,相关系数为-0.7386,P值为0.023. 结论对与SARS患者接触的医务人员,采取积极有效的防护措施能大大降低感染的风险,从而保护其身体健康.     

北京地区医务人员SARS感染的分析

目的　探讨医务人员SARS医院感染的危险因素。方法　对北京地区 2 0 0 3年 3月 2 0日～ 2 0 0 3年 5月 31日 6 6 6所医院进行医务人员SARS感染调查。结果　医务人员SARS感染的发病期较社会人群前移 ,综合门 (急 )诊医务人员SARS感染发病率占医务人员感染构成比 71 34% ,其中护士占 4 8 81% ,医生占 35 4 9% ;年龄 <4 0岁占 83 5 8% ;医务人员感染暴发为三级医院为主 6 9 2 8%。结论　由于信息封闭、指导诊断失误和控制措施不利导致SARS在北京地区暴发 ,医务人员是首批受感染者同时也是医院感染的传播链 ;必须在人类与疾病的斗争中加强医务人员的职业防护与保健。     

The 2003 SARS outbreak and its impact on infection control practices

Severe Acute Respiratory Syndrome (SARS) emerged recently as a new infectious disease that was transmitted efficiently in the healthcare setting and particularly affected healthcare workers (HCWs), patients and visitors. The efficiency of transmission within healthcare facilities was recognised following significant hospital outbreaks of SARS in Canada, China, Hong Kong, Singapore, Taiwan and Vietnam. The causative agent of SARS was identified as a novel coronavirus, the SARS coronavirus. This was largely spread by direct or indirect contact with large respiratory droplets, although airborne transmission has also been reported. High infection rates among HCWs led initially to the theory that SARS was highly contagious and the concept of 'super-spreading events'. Such events illustrated that lack of infection control (IC) measures or failure to comply with IC precautions could lead to large-scale hospital outbreaks. SARS was eventually contained by the stringent application of IC measures that limited exposure of HCWs to potentially infectious individuals. As the 'global village' becomes smaller and other microbial threats to health emerge, or re-emerge, there is an urgent need to develop a global strategy for infection control in hospitals. This paper provides an overview of the main IC practices employed during the 2003 SARS outbreak, including management measures, dedicated SARS hospitals, personal protective equipment, isolation, handwashing, environmental decontamination, education and training. The psychological and psychosocial impact on HCWs during the outbreak are also discussed. Requirements for IC programmes in the post-SARS period are proposed based on the major lessons learnt from the SARS outbreak.     

Quarantine for SARS, Taiwan

During the 2003 outbreak of severe acute respiratory syndrome (SARS) in Taiwan, >150,000 persons were quarantined, 24 of whom were later found to have laboratory-confirmed SARS-coronavirus (SARS-CoV) infection. Since no evidence exists that SARS-CoV is infective before the onset of symptoms and the quarantined persons were exposed but not symptomatic, we thought the quarantine's effectiveness should be investigated. Using the Taiwan quarantine data, we found that the onset-to-diagnosis time of previously quarantined confirmed case-patients was significantly shortened compared to that for those who had not been quarantined. Thus, quarantine for SARS in Taiwan screened potentially infective persons for swift diagnosis and hospitalization after onset, thereby indirectly reducing infections. Full-scale quarantine measures implemented on April 28 led to a significant improvement in onset-to-diagnosis time of all SARS patients, regardless of previous quarantine status. We discuss the temporal effects of quarantine measures and other interventions on detection and isolation as well as the potential usefulness of quarantine in faster identification of persons with SARS and in improving isolation measures.     

SARS-CoV特异性抗体产生规律的初步研究

目的 研究严重急性呼吸综合征(SARS)患者感染后体内病毒特异性抗体产生规律。方法 收集临床确诊为SARS患者的血清和非SARS人群血清标本,用IgM捕获法、间接法和抗原夹心法三种不同方法检测抗SARS病毒特异性IgM、IgG和总抗体。结果 检测146份临床诊断为SARS的患者不同发病时间血清标本,三种抗体阳性率分别为61.64％、53.43％和69.86％;SARS病毒特异性IgM、IgG抗体的最早检出时间分别在发病第7天和第12天,特异性IgM抗体最短在发病后42天消失。三种方法检测70份甲型肝炎患者血清时,均有2份非特异阳性反应,检测127份其他病种血清均阴性,1例密切接触SARS患者的医务人员SARS特异性IgG抗体和总抗体均阳性,三种检测方法均不受类风湿因子影响。结论 与其他病毒感染相比,SARS病毒感染者的特异性IgM抗体检出时间较晚,且持续时间较短;三种检测方法均有较好的特异性和敏感性,可用于SARS的流行病学调查和临床诊断的确认和补充,但不适用于SARS的早期诊断。     

Lack of SARS transmission and U.S. SARS case-patient

In early April 2003, severe acute respiratory syndrome (SARS) was diagnosed in a Pennsylvania resident after his exposure to persons with SARS in Toronto, Canada. To identify contacts of the case-patient and evaluate the risk for SARS transmission, a detailed epidemiologic investigation was performed. On the basis of this investigation, 26 persons (17 healthcare workers, 4 household contacts, and 5 others) were identified as having had close contact with this case-patient before infection-control practices were implemented. Laboratory evaluation of clinical specimens showed no evidence of transmission of SARS-associated coronavirus (SARS-CoV) infection to any close contact of this patient. This investigation documents that, under certain circumstances, SARS-CoV is not readily transmitted to close contacts, despite ample unprotected exposures. Improving the understanding of risk factors for transmission will help focus public health control measures.     

SARS医院感染的流行病学和预防控制措施研究

目的 探讨严重急性呼吸综合征(SARS)医院感染的流行病学特点和预防控制措施。方法选择某综合性医院3～4月份收治和医院感染的SARS病例，进行个案调查和发病所在科室的流行病学侦查。结果 (1)流行病学特点：时间分布在3月中旬和下旬有两个发病高峰，地理分布：发病病例主要集中住院大楼西单元的5个楼层的4、5号病房，人群分布：住院患者多年龄较大且合并较严重的基础病，而受染的医护人员以工作在一线的中青年为主；(2)输人性病例是导致医院感染的第一代传染源，医院内继发传染的住院者和医护人员是进一步扩散蔓延的第2批传染源；(3)研究发现近距离空气传播和密切接触传播为本次SARS医院感染的主要传播途径，同时还提示：存在气溶胶经病房排风系统垂直长距离传播的可能性；(4)控制隔离传染源、加强病区通风换气和定时消毒、关闭空调新风系统、医护人员加强防护等各项措施采取后，医院感染得到有效控制。结论 医院感染是SARS流行初期的主要形式，该院医护人员的受染方式前期以医院内传染为主，后期以门急诊窗口岗位受染较为突出，通过采取针对性预防控制措施，SARS医院感染是可控可防的。     

北京市某医院传染性非典型肺炎医院内感染传播途径的初步调查

目的：探讨传染性非典型肺炎[严重急性呼吸综合征(SARS)]医院感染的传播途径。方法：选择北京市某综合性医院3月2～31日期间收治和医院感染的10例SARS病例，进行个案调查和发病所在科室的流行病学侦查。结果：(1)发病病例的地理分布主要集中在住院大楼西单元的5个楼层的4、5号病房，住院患者多数年龄较大且合并较严重的基础病；(2)输入性病例是导致医院感染的第一代传染源，医院内继发感染的住院者是进一步扩散蔓延的第二批传染源，同时不排除隐性带病毒者(曾密切接触SARS病例而未发病者)作为潜在传染源的可能；(3)资料分析结果支持近距离飞沫传播和密切接触传播为该次SARS医院感染的主要传播途径，同时还提示：存在气溶胶(飞沫核)经病房排风系统垂直长距离传播的可能性。结论：医院感染是SARS流行初期的主要形式。其传播途径除近距离飞沫传播和密切接触外，应进一步收集和积累是否存在气溶胶(或飞沫核)长距离传播的流行病学和实验科学证据。     

Epidemiologic study and containment of a nosocomial outbreak of severe acute respiratory syndrome in a medical center in Kaohsiung, Taiwan.

OBJECTIVE: We conducted an epidemiologic investigation at the beginning of a nosocomial outbreak of severe acute respiratory syndrome (SARS) to clarify the dynamics of SARS transmission, the magnitude of the SARS outbreak, and the impact of the outbreak on the community. METHODS: We identified all potential cases of nosocomially acquired SARS, linked them to the most likely infection source, and described the hospital containment measures. SETTING: A 2,300-bed medical center in Kaohsiung, Taiwan. RESULTS: A total of 55 cases of SARS were identified, and 227 hospital workers were quarantined. The index patient and neighboring patients were isolated. A chest physician team reviewed medical charts and chest radiographs and monitored the development of SARS in patients staying in the ward. The presence of underlying lung disease and immunocompromise in some patients made the diagnosis of SARS difficult. Some cases of SARS were diagnosed after the patients had died. Medical personnel were infected only if they cared for patients with unrecognized SARS, and caretakers played important roles in transmission of SARS to family members. As the number of cases of nosocomial SARS increased, the hospital closed the affected ward and expedited construction of negative-pressure rooms on other vacated floors for patient cohorting, and the last case in the hospital was identified 1 week later. CONCLUSIONS: Timely recognition of SARS is extremely important. However, given the limitations of SARS testing, possible loss of epidemic links, and the nonspecific clinical presentations in hospitalized patients, it is very important to establish cohorts of persons with low, medium, and high likelihoods of SARS acquisition. Rapid closure of affected wards may minimize the impact on hospital operations. Establishment of hospitals dedicated to appropriate treatment of patients with SARS might minimize the impact of the disease in future epidemics.     

天津市传染性非典型肺炎流行特点及主要控制措施效果评价

目的：分析天津市传染性非典型肺炎[严重急性呼吸综合征(SARS)]流行病学特征，对主要控制措施的效果进行初步评价。方法：采用自行设计的病例报告表，全市统一的流行病学个案调查表及病例接触者、密切接触者树状分布图，深入病房、家庭、社区、团体等对病例及接触者进行调查。结果：以发病时间计算，自2003年4月13日至5月8日，包括输入病例在内发病175例，发病率为1．9／10万，其中死亡14例，病死率达8．O％。整个流行过程不足1个月，流行特点：1例“超级传播者”直接或间接传染了全市94．3％的病例；呈现以A、B、C 3家医院聚集发病为特点的爆发性流行，占全市病例的68．6％，3家医院外的家庭聚集发病占全市病例的14．3％，同事间传播为2．3％，散发者为9．1％，这些散发者未造成接触者感染；早期医务人员发病较多，占总病例数的38．2％，流行全过程参加SARS救治工作的1975名医护人员的总感染率为3．4％；全部流行过程传染源明确，传染链清晰，全市仅3例患者未找到传染源，占病例总数的2％；在10例源头病例中仅“超级传播者”和另一病例传染了其接触者，其他传染源由于及时隔离未造成任何传播。结论：SARS是严重急性呼吸系统传染病，如能及时准确地掌握传染链并进行范围适当、及时有效的封闭及隔离措施，以科学的方法提高全民的警觉度，传染链可能在较短时间内被切断，从而控制传播。     

Update: severe acute respiratory syndrome--Toronto,Canada, 2003

Severe acute respiratory syndrome (SARS) was first recognized in Toronto in a woman who returned from Hong Kong on February 23, 2003 (1). Transmission to other persons resulted subsequently in an outbreak among 257 persons in several Greater Toronto Area (GTA) hospitals. After implementation of provincewide public health measures that included strict infection-control practices, the number of recognized cases of SARS declined substantially, and no cases were detected after April 20. On April 30, the World Health Organization (WHO) lifted a travel advisory issued on April 22 that had recommended limiting travel to Toronto. This report describes a second wave of SARS cases among patients, visitors, and health-care workers (HCWs) that occurred at a Toronto hospital approximately 4 weeks after SARS transmission was thought to have been interrupted. The findings indicate that exposure to hospitalized patients with unrecognized SARS after a provincewide relaxation of strict SARS control measures probably contributed to transmission among HCWs. The investigation underscores the need for monitoring fever and respiratory symptoms in hospitalized patients and visitors, particularly after a decline in the number of reported SARS cases.     

The SARS outbreak in a general hospital in Tianjin, China -- the case of super-spreader

Severe acute respiratory syndrome (SARS) is a newly emerged infectious disease with a high case-fatality rate and devastating socio-economic impact. In this report we summarized the results from an epidemiological investigation of a SARS outbreak in a hospital in Tianjin, between April and May 2003. We collected epidemiological and clinical data on 111 suspect and probable cases of SARS associated with the outbreak. Transmission chain and outbreak clusters were investigated. The outbreak was single sourced and had eight clusters. All SARS cases in the hospital were traced to a single patient who directly infected 33 people. The patients ranged from 16 to 82 years of age (mean age 38.5 years); 38.7% were men. The overall case fatality in the SARS outbreak was 11.7% (13/111). The outbreak lasted around 4 weeks after the index case was identified. SARS is a highly contagious condition associated with substantial case fatality; an outbreak can result from one patient in a relatively short period. However, stringent public health measures seemed to be effective in breaking the disease transmission chain.     

广东省13家医院医护人员严重急性呼吸综合征医院内感染情况

目的　分析收治严重急性呼吸综合征 (SARS)患者重点医院医护人员发生SARS院内感染的因素 ,评价干预措施。方法　通过对 13家重点医院收治SARS患者的数量及病情、医护人员SARS的发病率、医院性质、病区 (科室 )环境及隔离措施调查 ,分析医护人员发生SARS院内感染的原因。结果　 13家医院共收治SARS患者 84 1例 ,参加诊治工作的 2 36 5名医护人员中 2 85人发病。综合性医院、收治危重患者较多的医院、医护人员个人防护不到位的医院医护人员发病率较高 (93/2 85 ,32 .6 3% ) ;独立病房收治SARS患者的医院、具有感染科或隔离病区 (包括临时开设的隔离病区 )的医院医护人员发病率较低。结论　收治SARS患者的病情、医院性质、病区 (科室 )环境、个人防护状况是医护人员感染SARS的危险因素     

The impact of community psychological responses on outbreak control for severe acute respiratory syndrome in Hong Kong

OBJECTIVE: To examine the public's knowledge and perception of SARS and the extent to which various precautionary measures have been adopted. DESIGN: Cross sectional survey. SETTING: General population of Hong Kong at the height of the SARS outbreak (29 March to 6 April 2003). PARTICIPANTS: 1115 ethnic Chinese adults. Main results: Forty per cent did not recognise fomites as a possible mode of transmission whereas 55.1% believed that the infection could be transmitted airborne. A large proportion (30.1%) believed they were very or somewhat likely to contract SARS while only one quarter believed they were very likely to survive if they contracted the disease, benchmarked against an actual case fatality ratio of 2.8% at the time of the survey and 15%-20% according to current best estimates. Precautionary measures directed against person to person droplet spread were generally adopted by most while the prevention of transmission through fomites was not practised as frequently. Respondents with higher risk perceptions and a moderate level of anxiety were most likely to take comprehensive precautionary measures against the infection, as were older, female, more educated people as well as those with a positive contact history and SARS-like symptoms. CONCLUSIONS: The findings demonstrate that the promotion of protective personal health practices to interrupt the self sustaining transmission of the SARS virus in the community must take into account background perceptions of risk and anxiety levels of the public at large. Continuing public education about preventive measures should be targeted at the identified groups with low current uptake of precautions.