SARS transmission and hospital containment

An outbreak of severe acute respiratory syndrome (SARS) was detected in Singapore at the beginning of March 2003. The outbreak, initiated by a traveler to Hong Kong in late February 2003, led to sequential spread of SARS to three major acute care hospitals in Singapore. The critical factor in containing this outbreak was early detection and complete assessment of movements and follow-up of patients, healthcare workers, and visitors who were contacts. Visitor records were important in helping identify exposed persons who could carry the infection into the community. In the three hospital outbreaks, three different containment strategies were used to contain spread of infection: closing an entire hospital, removing all potentially infected persons to a dedicated SARS hospital, and managing exposed persons in place. On the basis of this experience, if a nosocomial outbreak is detected late, a hospital may need to be closed in order to contain spread of the disease. Outbreaks detected early can be managed by either removing all exposed persons to a designated location or isolating and managing them in place.     

Was WHO SARS-related travel advisory for Toronto ethical?

Freedom of movement is undoubtedly a fundamental international right. However, circumstances may arise where that right must be curtailed. Was the 2003 SARS outbreak in Toronto one such circumstance? Guéna?l R.M. Rodier thinks WHO's decision to impose a SARS-related travel advisory was justifiable, even reasonable, though it caused a loss of over $1.1 billion in the Greater Toronto Area. That travel to an infected area was the most common epidemiological link with SARS infections supports Rodier's position. However, as suggested in the Naylor report, issuing a travel advisory does not keep infected individuals from leaving Toronto and such individuals account for 5 of 6 cases where SARS was spread from Canada. That alone would discount Rodier's argument and the WHO decision on purely logistical grounds. But there is an ethical question as well. Was the travel advisory implemented fairly? This question is best judged using Nancy E. Kass's framework for public health. From that framework, two points are placed in immediate relief. First, the Toronto authorities were not given an opportunity to state their case to WHO before the travel advisory was implemented. Second, the framework requires that burdens be distributed fairly and the travel advisory did not do that, or even attempt to do so.     

Severe acute respiratory syndrome surveillance in Australia.

In March 2003, the World Health Organization (WHO) issued a global alert recommending active worldwide surveillance for severe acute respiratory syndrome (SARS). This paper describes the epidemiological features of cases reported by Australian states and territories to the Australian Government Department of Health and Ageing between 17 March and 31 July 2003. There were 138 people investigated for SARS: 111 as suspect and 27 as probable. Five probable cases were reported to WHO after review of other possible diagnoses and Australia-specific exclusion criteria had been applied. An additional probable case identified by laboratory testing overseas, but who was not under investigation when in Australia, was also reported to WHO. The method by which surveillance for SARS was rapidly established provided an opportunity to examine Australia's planning and preparedness for future respiratory disease epidemics such as influenza.     

Interferon-beta 1a and SARS coronavirus replication

A global outbreak of severe acute respiratory syndrome (SARS) caused by a novel coronavirus began in March 2003. The rapid emergence of SARS and the substantial illness and death it caused have made it a critical public health issue. Because no effective treatments are available, an intensive effort is under way to identify and test promising antiviral drugs. Here, we report that recombinant human interferon-beta 1a potently inhibits SARS coronavirus replication in vitro.     

Environmental transmission of SARS at Amoy Gardens

Recent investigations into the March 2003 outbreak of SARS in Hong Kong have concluded that environmental factors played an important role in the transmission of the disease. These studies have focused on a particular outbreak event, the rapid spread of SARS throughout Amoy Gardens, a large, private apartment complex. They have demonstrated that, unlike a typical viral outbreak that is spread through person-to-person contact, the SARS virus in this case was spread primarily through the air. High concentrations of viral aerosols in building plumbing were drawn into apartment bathrooms through floor drains. The initial exposures occurred in these bathrooms. The virus-laden air was then transported by prevailing winds to adjacent buildings at Amoy Gardens, where additional exposures occurred. This article reviews the results of the investigations and provides recommendations for maintenance and other measures that building owners can take to help prevent environmental transmission of SARS and other flulike viruses in their buildings.     

Understanding the spatial clustering of severe acute respiratory syndrome (SARS) in Hong Kong

We applied cartographic and geostatistical methods in analyzing the patterns of disease spread during the 2003 severe acute respiratory syndrome (SARS) outbreak in Hong Kong using geographic information system (GIS) technology. We analyzed an integrated database that contained clinical and personal details on all 1,755 patients confirmed to have SARS from 15 February to 22 June 2003. Elementary mapping of disease occurrences in space and time simultaneously revealed the geographic extent of spread throughout the territory. Statistical surfaces created by the kernel method confirmed that SARS cases were highly clustered and identified distinct disease "hot spots." Contextual analysis of mean and standard deviation of different density classes indicated that the period from day 1 (18 February) through day 16 (6 March) was the prodrome of the epidemic, whereas days 86 (15 May) to 106 (4 June) marked the declining phase of the outbreak. Origin-and-destination plots showed the directional bias and radius of spread of superspreading events. Integration of GIS technology into routine field epidemiologic surveillance can offer a real-time quantitative method for identifying and tracking the geospatial spread of infectious diseases, as our experience with SARS has demonstrated.     

Border screening for SARS

With the rapid international spread of severe acute respiratory syndrome (SARS) from March through May 2003, Canada introduced various measures to screen airplane passengers at selected airports for symptoms and signs of SARS. The World Health Organization requested that all affected areas screen departing passengers for SARS symptoms. In spite of intensive screening, no SARS cases were detected. SARS has an extremely low prevalence, and the positive predictive value of screening is essentially zero. Canadian screening results raise questions about the effectiveness of available screening measures for SARS at international borders.     

Influenza and SARS: the impact of viral pandemics on maritime health

Global travel and transport play a critical role in the spread of infections. We see this clearly in the first two pandemics of the 21st century: SARS and influenza H1N1-2009. Although air travel contributed to dissemination in these two pandemics, the travel restrictions, quarantines, and heightened vigilance which resulted had an impact on maritime health. Seasonal, pandemic, and avian influenza have some important differences with regards to exposure risks, infectivity, and severity. Most of the data for maritime influenza outbreaks focus on seasonal influenza on cruise ships, but influenza among crew members occurs due to close working conditions and is potentially preventable with staff vaccination programs. To date, avian influenza has low human-to-human transmission; infection typically requires close contact with poultry, but presents with severe disease and a high fatality rate. Pandemic (swine) influenza was readily transmitted between people, including young adults, and caused severe illness in high-risk groups including pregnant women, children, and those with co-morbidities and obesity. In contrast, SARS had lower infectivity compared to influenza, and a longer incubation period. These characteristics slowed its propagation enough that outbreak control measures, such as isolation of infected cases and quarantine of exposed but well persons, were effective in terminating this pandemic. No effective vaccine exists for SARS at this time, whereas countries were able to deploy millions of doses of pandemic influenza vaccine within 7 months after the outbreak was first recognized in Mexico. The lack of a protective vaccine and the higher case fatality rate in SARS will mean that stringent quarantine measures may still be required for outbreak control if SARS ever occurs again. Compliance with international health regulations, and the ability to adapt these to maritime health needs, will be important in the shipping industry.     

How would schools step up public health measures to control spread of SARS?

The severe acute respiratory syndrome (SARS) is a rapidly progressive, and sometime fatal disease with more than 1800 patients in over a dozen countries in Asia, Europe, and North America (including the United States and Canada) within two months. On 12 March 2003, the World Health Organisation (WHO) issued a global alert about SARS so it became a global challenge. Strengthening the public health measures at schools would protect children as well as providing the students an opportunity to learn about infectious disease control through life event approach. The public health measures at schools include two important components: basic understanding of the disease so schools would put on high alert on caution cases, and the measures to improve environmental hygiene at schools and preventive measures to stop infectious disease transmission. This will help to empower the whole community the readiness to deal with other outbreaks in the future.     

Update: Severe acute respiratory syndrome--United States, 2003

CDC continues to work with state and local health departments, the World Health Organization (WHO), and other partners to investigate cases of severe acute respiratory syndrome (SARS). During November 1, 2002-April 30, 2003, a total of 5,663 SARS cases were reported to WHO from 26 countries, including the United States; 372 deaths (case-fatality proportion: 6.6%) have been reported. This report updates information on reported SARS cases among U.S. residents and provides an overview regarding CDC's issuance of travel alerts and advisories.     

SARS epidemic in the world, from March to July 2003: what lessons can be learned from press coverage?

In the period from March to July 2003, the French and international press published a great deal of information and news about the first occurrence of the global SARS epidemic, due to its threat on numerous developed or lesser developed countries. The author collected all of the available French daily newspapers, dating from March 17 to July 31, 2003, and in particular every edition of the five national papers relaying any information on the epidemic covered on the front page. The review and study of these papers' headlines highlight the intense media coverage given in the French press primarily from April to May 2003, accompanied by an evolution of the themes being tackled above all which concerned the world-wide alert from WHO which originally comprised the countries of the East (mainly China) as well as Canada, European countries (including France) and finally whose scale reached that of global proportions. Due to this situation, certain countries adopted more drastic protective measures.     

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.     

The evolving WHO: Implications for global health security

Abstract

The World Health Organization (WHO) is central to the international community's efforts to control infectious disease outbreaks. In recent years, however, the Organization's powers have undergone substantial revision following a series of interconnected global events including the 2003 severe acute respiratory syndrome outbreak, the revised International Health Regulations, the emergence and spread of avian influenza, and more recently, the 2009 H1N1 Swine Flu pandemic. This paper explores how the WHO's role, authority and autonomy have been shaped and re-shaped, and examines what this may mean for the future of global health security.     

Severe acute respiratory syndrome (SARS) and healthcare workers

The recent outbreak of severe acute respiratory synt drome (SARS) was spread by international air travel, a direct result of globalization. The disease is caused by a novel coronavirus, transmitted from human to human by droplets or by direct contact. Healthcare workers (HCWs) were at high risk and accounted for a fifth of all cases globally. Risk factors for infection in HCWs included lack of awareness and preparedness when the disease first struck, poor institutional infection control measures, lack of training in infection control procedures, poor compliance with the use of personal protection equipment (PPE), exposure to high-risk procedures such as intubation and nebulization, and exposure to unsuspected SARS patients. Measures to prevent nosocomial infection included establishing isolation wards for triage, SARS patients, and step-down; training and monitoring hospital staff in infection-control procedures; active and passive screening of HCWs; enforcement of droplet and contact precautions; and compliance with the use of PPE.     

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.     

Public health interventions and SARS spread, 2003

The 2003 outbreak of severe acute respiratory syndrome (SARS) was contained largely through traditional public health interventions, such as finding and isolating case-patients, quarantining close contacts, and enhanced infection control. The independent effectiveness of measures to "increase social distance" and wearing masks in public places requires further evaluation. Limited data exist on the effectiveness of providing health information to travelers. Entry screening of travelers through health declarations or thermal scanning at international borders had little documented effect on detecting SARS cases; exit screening appeared slightly more effective. The value of border screening in deterring travel by ill persons and in building public confidence remains unquantified. Interventions to control global epidemics should be based on expert advice from the World Health Organization and national authorities. In the case of SARS, interventions at a country's borders should not detract from efforts to identify and isolate infected persons within the country, monitor or quarantine their contacts, and strengthen infection control in healthcare settings.     

Update: outbreak of severe acute respiratory syndrome--worldwide, 2003

CDC and the World Health Qrganization (WHO) are continuing to investigate the multicountry outbreak of unexplained atypical pneumonia referred to as severe acute respiratory syndrome (SARS). Pending development of confirmatory laboratory testing capacity, CDC's interim suspected SARS case definition is based on clinical criteria and epidemiologic linkage to other SARS cases or areas with community transmission of SARS. This case definition will be updated periodically as new information becomes available. Epidemiologic and laboratory investigations of SARS are ongoing. As of April 2, 2003, a total of 2,223 suspected and/or probable SARS cases have been reported to WHO from 16 countries, including the United States. The reported SARS cases include 78 deaths (case-fatality proportion: 3.5%). This report summarizes SARS cases among U.S. residents and surveillance and prevention activities in the United States.     

A growing global network's role in outbreak response: AFHSC-GEIS 2008-2009

A cornerstone of effective disease surveillance programs comprises the early identification of infectious threats and the subsequent rapid response to prevent further spread. Effectively identifying, tracking and responding to these threats is often difficult and requires international cooperation due to the rapidity with which diseases cross national borders and spread throughout the global community as a result of travel and migration by humans and animals. From Oct.1, 2008 to Sept. 30, 2009, the United States Department of Defense's (DoD) Armed Forces Health Surveillance Center Global Emerging Infections Surveillance and Response System (AFHSC-GEIS) identified 76 outbreaks in 53 countries. Emerging infectious disease outbreaks were identified by the global network and included a wide spectrum of support activities in collaboration with host country partners, several of which were in direct support of the World Health Organization's (WHO) International Health Regulations (IHR) (2005). The network also supported military forces around the world affected by the novel influenza A/H1N1 pandemic of 2009. With IHR (2005) as the guiding framework for action, the AFHSC-GEIS network of international partners and overseas research laboratories continues to develop into a far-reaching system for identifying, analyzing and responding to emerging disease threats.     

Update: Severe acute respiratory syndrome--United States, 2003

CDC and the World Health Organization (WHO) are continuing to investigate the multicountry outbreak of severe acute respiratory syndrome (SARS). This report updates information on reported SARS cases among U.S. residents and summarizes information on patients with no recent travel outside the United States.     

Responding to global infectious disease outbreaks: lessons from SARS on the role of risk perception, communication and management

With increased globalisation comes the likelihood that infectious disease appearing in one country will spread rapidly to another, severe acute respiratory syndrome (SARS) being a recent example. However, although SARS infected some 10,000 individuals, killing around 1000, it did not lead to the devastating health impact that many feared, but a rather disproportionate economic impact. The disproportionate scale and nature of this impact has caused concern that outbreaks of more serious disease could cause catastrophic impacts on the global economy. Understanding factors that led to the impact of SARS might help to deal with the possible impact and management of such other infectious disease outbreaks. In this respect, the role of risk--its perception, communication and management--is critical. This paper looks at the role that risk, and especially the perception of risk, its communication and management, played in driving the economic impact of SARS. It considers the public and public health response to SARS, the role of the media and official organisations, and proposes policy and research priorities for establishing a system to better deal with the next global infectious disease outbreak. It is concluded that the potential for the rapid spread of infectious disease is not necessarily a greater threat than it has always been, but the effect that an outbreak can have on the economy is, which requires further research and policy development.