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.     

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.     

Severe acute respiratory syndrome, Beijing, 2003

The largest outbreak of severe acute respiratory syndrome (SARS) struck Beijing in spring 2003. Multiple importations of SARS to Beijing initiated transmission in several healthcare facilities. Beijing's outbreak began March 5; by late April, daily hospital admissions for SARS exceeded 100 for several days; 2,521 cases of probable SARS occurred. Attack rates were highest in those 20-39 years of age; 1% of cases occurred in children <10 years. The case-fatality rate was highest among patients >65 years (27.7% vs. 4.8% for those 20-64 years, p < 0.001). Healthcare workers accounted for 16% of probable cases. The proportion of case-patients without known contact to a SARS patient increased significantly in May. Implementation of early detection, isolation, contact tracing, quarantine, triage of case-patients to designated SARS hospitals, and community mobilization ended the outbreak.     

SARS preparedness. Revisiting the procedures to protect staff and help prevent or contain an outbreak

Last year, more than 8,000 people worldwide contracted severe acute respiratory syndrome (SARS), leading to 774 deaths. Although transmission of the disease was quickly controlled, with the outbreak declared over by July, there is concern that SARS could in fact be a seasonal disease and that another outbreak could occur in 2004. In early January, Chinese health officials confirmed the first non-laboratory-related SARS case since the initial outbreak was contained. The threat of another outbreak underscores the importance of having a response plan in place to safeguard the health of your community and your staff. In this article, we discuss the latest information on the risks of acquiring SARS, review recent recommendations from the U.S. Centers for Disease Control and Prevention (CDC), discuss the role of hospital facility and clinical engineers in SARS preparations, and update ECRI's recommendations for infection control procedures during equipment servicing. (ECRI first addressed this issue in two June 2003 Health Devices Guidance Articles.) In two appendixes to the current article, we present CDC guidance on patient isolation in an airborne infection isolation room and offer a navigational guide to CDC's SARS Web site.     

Long-term psychological and occupational effects of providing hospital healthcare during SARS outbreak

Healthcare workers (HCWs) found the 2003 outbreak of severe acute respiratory syndrome (SARS) to be stressful, but the long-term impact is not known. From 13 to 26 months after the SARS outbreak, 769 HCWs at 9 Toronto hospitals that treated SARS patients and 4 Hamilton hospitals that did not treat SARS patients completed a survey of several adverse outcomes. Toronto HCWs reported significantly higher levels of burnout (p = 0.019), psychological distress (p<0.001), and posttraumatic stress (p<0.001). Toronto workers were more likely to have reduced patient contact and work hours and to report behavioral consequences of stress. Variance in adverse outcomes was explained by a protective effect of the perceived adequacy of training and support and by a provocative effect of maladaptive coping style and other individual factors. The results reinforce the value of effective staff support and training in preparation for future outbreaks.     

Atypical SARS in geriatric patient

We describe an atypical presentation of severe acute respiratory syndrome (SARS) in a geriatric patient with multiple coexisting conditions. Interpretation of radiographic changes was confounded by cardiac failure, with resolution of fever causing delayed diagnosis and a cluster of cases. SARS should be considered even if a contact history is unavailable, during an ongoing outbreak.     

SARS risk perception, knowledge, precautions, and information sources, the Netherlands

Severe acute respiratory syndrome (SARS)-related risk perceptions, knowledge, precautionary actions, and information sources were studied in the Netherlands during the 2003 SARS outbreak. Although respondents were highly aware of the SARS outbreak, the outbreak did not result in unnecessary precautionary actions or fears.     

Viral load distribution in SARS outbreak

An unprecedented community outbreak of severe acute respiratory syndrome (SARS) occurred in the Amoy Gardens, a high-rise residential complex in Hong Kong. Droplet, air, contaminated fomites, and rodent pests have been proposed to be mechanisms for transmitting SARS in a short period. We studied nasopharyngeal viral load of SARS patients on admission and their geographic distribution. Higher nasopharyngeal viral load was found in patients living in adjacent units of the same block inhabited by the index patient, while a lower but detectable nasopharyngeal viral load was found in patients living further away from the index patient. This pattern of nasopharyngeal viral load suggested that airborne transmission played an important part in this outbreak in Hong Kong. Contaminated fomites and rodent pests may have also played a role.     

SARS流行期间公众心理状况调查

目的 探讨SARS流行期间公众心理健康状况，为心理干预提供依据。方法采用SCL-90量表，对2844名学生及城市社区居民和农村居民进行SARS流行期间的心理健康状况问卷调查。结果（1）SARS流行期间公众心理健康状况较全国常模差。（2）不同类群公众在SARS流行期间心态变化不尽相同，产生的心理卫生问题也不同。结论（1）SARS流行期间公众的心理危机问题值得关注。（2）SARS及其它公共卫生事件发生期间的心理危机干预非常必要，但要有针对性。     

SARS in hospital emergency room

Thirty-one cases of severe acute respiratory syndrome (SARS) occurred after exposure in the emergency room at the National Taiwan University Hospital. The index patient was linked to an outbreak at a nearby municipal hospital. Three clusters were identified over a 3-week period. The first cluster (5 patients) and the second cluster (14 patients) occurred among patients, family members, and nursing aids. The third cluster (12 patients) occurred exclusively among healthcare workers. Six healthcare workers had close contact with SARS patients. Six others, with different working patterns, indicated that they did not have contact with a SARS patient. Environmental surveys found 9 of 119 samples of inanimate objects to be positive for SARS coronavirus RNA. These observations indicate that although transmission by direct contact with known SARS patients was responsible for most cases, environmental contamination with the SARS coronavirus may have lead to infection among healthcare workers without documented contact with known hospitalized SARS patients.     

Defining the new normal

Throughout the extended SARS outbreak, healthcare organizations across Ontario operated under directives that imposed significant changes to patient and operational practices. The outbreak dramatically illustrated the critical need to transform healthcare organizations to a "new normal" state of operation to respond to the ease by which contagious diseases can spread globally.     

一起传染性非典型肺炎爆发的“超级传播者”和传播链分析

目的：了解严重急性呼吸综合征(SARS)爆发案例的传播过程，分析SARS病例不同阶段的传染性和不同接触方式的危险性。方法：设计统一调查表，用查阅病历、面对面调查和电话调查相结合的方式进行，以指征病例为起点进行线索追踪和个案调查。用传播链示意图分析传播关系，用接触史分析示意图分析传染性。结果：共追查到与该案例传播链相关的接触者207人，发病36例，死亡1例，总罹患率为17％。其中指征病例和1名二代病例分别直接传播了12例和13例续发病例，其传播过程可以用清晰的传播链加以描述；所有36例病例均与前代病例的症状期有密切接触史，家族传播链中85％的病例都与前代病例症状期的第3—5天有过接触，发病前后均接触和仅发病后接触者罹患率分别为70％和67％，差异无显著性；仅与前代病例潜伏期接触的15名同柜台同事、29名同班同学无发病，38名与医护人员发病前或发病初期密切接触的家属无发病。结论：该案例所有的续发病例都有与症状期病例密切接触史；未观察到SARS患者在其潜伏期内存在传染性。     

Management of inpatients exposed to an outbreak of severe acute respiratory syndrome (SARS)

This is a prospective observational study of a cohort of inpatients exposed to a severe acute respiratory syndrome (SARS) outbreak. Strict infection control policies were instituted. The 70 patients exposed to the SARS outbreak were isolated from the rest of the hospital. They were triaged, quarantined and cohorted in three open plan wards. Selective isolation was carried out immediately when symptoms and signs suspicious of SARS manifested clinically. The patients' ages ranged from 21 to 90 years and 56% had surgery before the quarantine. Sixteen patients with unexplained fever during the period of quarantine were isolated, seven of whom were eventually diagnosed with probable SARS. The crude incidence of SARS in our cohort was 10%. The SARS case fatality was 14%. No secondary transmission of the SARS virus within the cohort was observed. Strict infection control, together with appropriate triaging, cohorting and selective isolation, is an effective and practical model of intervention in cohorts exposed to a SARS outbreak. Such a management strategy eases the logistic constraints imposed by demands for large numbers of isolation facilities in the face of a massive outbreak.     

Control of Severe Acute Respiratory Syndrome in Singapore

A Severe Acute Respiratory Syndrome (SARS) outbreak occurred in Singapore from February to May 2003. A high vigilance for the disease, frequent and regular temperature monitoring, early case identification and isolation of patients, as well as tracing and home quarantine of contacts, played major roles in controlling the outbreak. Hospitals were dedicated to the screening and treatment of SARS patients. Within and between hospitals, movement by healthcare workers, patients and visitors were restricted, as was the number of hospital visitors. Staff education and audits of infection control practices also featured prominently. To prevent cross-border transmission, incoming travellers from SARS affected areas had to complete health declaration cards. They, as well as all outgoing travellers from Singapore, were monitored for fever. In the meantime, the public was urged to refrain from travelling to SARS affected regions. Containment elements targeting the community included school closure, public education on good hygiene and readily accessible public information. In response to a laboratory acquired SARS infection, laboratories were audited, and directives issued on the mandatory use of biosafety level 3 laboratories for SARS virus culture, and compliance of laboratory workers to biosafety guidelines.     

四川省首起家庭内暴发传染性非典型肺炎调查

目的 对四川省首起可疑传染性非典型肺炎(SARS)的家庭暴发病例进行流行病学调查，病原学、血清学检测，明确诊断。方法 对发生于2003年2月12日的首起家庭暴发病例进行流行病学调查，病原学和血清学检测。结果该起暴发发生于四川省广元市某厂，1家3口皆发病，有密切接触史，符合传染性非典型肺炎的临床诊断标准。患者鼻和咽拭子，上呼吸道分泌物标本，均未分离到流感病毒，禽流感病毒和肺炎衣原体。患者A恢复期血冠状病毒IgM和IgG抗体阳性，患者B恢复期血冠状病毒IgG抗体阳性，患者C急性期血冠状病毒和肺炎衣原体IgM抗体阳性。结论 该起暴发的流行病学、临床特征、血清学等均符合传染性非典型肺炎的诊断。为四川省首起传染性非典型肺炎疫情。     

Ultrastructural characterization of SARS coronavirus

Severe acute respiratory syndrome (SARS) was first described during a 2002-2003 global outbreak of severe pneumonia associated with human deaths and person-to-person disease transmission. The etiologic agent was initially identified as a coronavirus by thin-section electron microscopic examination of a virus isolate. Virions were spherical, 78 nm in mean diameter, and composed of a helical nucleocapsid within an envelope with surface projections. We show that infection with the SARS-associated coronavirus resulted in distinct ultrastructural features: double-membrane vesicles, nucleocapsid inclusions, and large granular areas of cytoplasm. These three structures and the coronavirus particles were shown to be positive for viral proteins and RNA by using ultrastructural immunogold and in situ hybridization assays. In addition, ultrastructural examination of a bronchiolar lavage specimen from a SARS patient showed numerous coronavirus-infected cells with features similar to those in infected culture cells. Electron microscopic studies were critical in identifying the etiologic agent of the SARS outbreak and in guiding subsequent laboratory and epidemiologic investigations.     

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.     

Factors associated with critical-care healthcare workers' adherence to recommended barrier precautions during the Toronto severe acute respiratory syndrome outbreak.

OBJECTIVE: To assess factors associated with adherence to recommended barrier precautions among healthcare workers (HCWs) providing care to critically ill patients with severe acute respiratory syndrome (SARS). SETTING: Fifteen acute care hospitals in Ontario, Canada. DESIGN: Retrospective cohort study. PATIENTS: All patients with SARS who required intubation during the Toronto SARS outbreak in 2003. PARTICIPANTS: HCWs who provided care to or entered the room of a SARS patient during the period from 24 hours before intubation until 4 hours after intubation. METHODS: Standardized interviews were conducted with eligible HCWs to assess their interactions with the SARS patient, their use of barrier precautions, their practices for removing personal protective equipment, and the infection control training they received. RESULTS: Of 879 eligible HCWs, 795 (90%) participated. In multivariate analysis, the following predictors of consistent adherence to recommended barrier precautions were identified: recognition of the patient as a SARS case (odds ratio [OR], 2.5 [95% confidence interval {CI}, 1.5-4.5); recent infection control training (OR for interactive training, 2.7 [95% CI, 1.7-4.4]; OR for passive training, 1.7 [95% CI, 1.0-3.0]), and working in a SARS unit (OR, 4.0 [95% CI, 1.8-8.9]) or intensive care unit (OR, 4.3 [95% CI, 2.0-9.0]). Two factors were associated with significantly lower rates of consistent adherence: the provision of care for patients with higher Acute Physiology and Chronic Health Evaluation (APACHE) II scores (OR for score APACHE II of 20 or greater, 0.4 [95% CI, 0.28-0.68]) and work on shifts that required more frequent room entry (OR for 6 or more entries per shift, 0.5 [95% CI, 0.32-0.86]). CONCLUSIONS: There were significant deficits in knowledge about self-protection that were partially corrected by education programs during the SARS outbreak. HCWs' adherence to self-protection guidelines was most closely associated with whether they provided care to patients who had received a definite diagnosis of SARS.     

一起小学校内乙型流感暴发的调查

2004年9月下旬，浙江省江山市某乡镇中心小学发生了一起由乙型流感病毒引起流行性感冒暴发。经调查本次乙型流感共发现患者65例，罹患率15．26％。     

从抗击非典斗争反思卫生与政治的关系

本文从政治角度对非典的爆发流行和我国抗击非典的斗争进行反思，依次论述了：卫生与政治的关系的历史演变过程，非典爆发流行的政治因素和政治影响，抗击非典的斗争及其胜利的政治意义，从抗击非典斗争中汲取政治上的经验教训。人们从中不难看出，在新的形势下卫生与政治的关系的新变化。