To date, severe acute respiratory syndrome (SARS) has sickened at least 8,400 individuals and killed more than 820 worldwide. Before public health officials in China recognized the significance of the initial outbreak of this new disease, infected travelers had sparked secondary outbreaks in several Asian nations and in Toronto, Ontario, Canada. The severity of the ensuing illness and its ready transmissibility severely challenged the medical care systems of affected countries.1, 2, 3, 4 Although much has been learned about SARS since the disease was first identified, many questions are unanswered. It is not yet known, for example, if the disease is seasonal, how it may be transmitted, and why certain individuals are “superspreaders” of infection.5, 6
SARS is characterized by a high degree of infectivity among close personal contacts, including treating health care workers.7, 8 To date, SARS infection has not produced a random pattern of contagious spread.1, 2, 3, 9, 10 The virus can contaminate buildings, fixtures, and patient care areas, but details of how contamination takes place and the persistence of infectious material are unknown.4 As yet, no antimicrobial agent (alone or in combination with other drugs such as corticosteroids) has been established as effective.
Worse yet, the disease is highly virulent. Despite widespread provision of intensive care, including endotracheal intubation and mechanical ventilation, the disease produced a case-fatality rate among hospitalized patients of 10% to 15%.11, 12, 13 Aggressive respiratory care increased the risk of disease transmission to treating health care workers.7, 8, 14, 15 The combination of ready transmissibility and virulence makes SARS a particularly dangerous disease, one that resembles the Class A bioterrorism agents (Table).
Table.
Characteristic | SARS | Bioterrorism Agent |
---|---|---|
The ability to cause serious illness or death | Yes | Yes |
Person-to-person transmission | Yes | Yes |
Prevented or treated with antibiotics, vaccines, or toxin antagonists if promptly diagnosed | Not as yet | Yes |
A rapid or unusual increase (hours to days) in the number of previously healthy persons with similar symptoms (eg, fever, respiratory, gastrointestinal, rash complaint) seeking care | Not as yet | Yes |
A cluster of previously healthy persons with similar symptoms who live, work, or recreate in a common geographic area | Yes | Yes |
Lower incident rates in those persons who are protected (eg, confined to home, no exposure to large crowds) | Yes | Yes |
High infectivity rate | Yes | Some agents |
Any patient arriving with known bioterrorism agent not present by natural dissemination (eg, smallpox, anthrax) | No | Yes |
An increase in reports of dead animals | Not as yet | Some agents |
Ease of cultivation, storage, and dissemination | No | Some agents |
An increased number of patients who die within 72 hours after admission to the hospital | Yes | Yes |
Because the first outbreaks of SARS and deaths occurred outside the United States, public concern in this country was intense, but short-lived. When the worldwide incidence of SARS declined this past spring, officials quickly declared victory. The June 18, 2003 edition of USA Today announced, “Experts: SARS Is Stopped.”5
This statement may be regretfully premature. It is extremely difficult to predict the course of a new epidemic disease, particularly one that is still being characterized. Anthony Fauci, head of the National Institute of Allergy and Infectious Diseases at the National Institutes of Health, offered a cautionary note. “We still have the same conditions in China that led to the emergence of this epidemic, so there's no reason to believe it's not going to happen again,” he observed. “We're just one case from the disease reappearing.”5
There are also historical reasons to worry. The influenza pandemic of 1918 to 1919 was a global disaster. First identified in Spain in February 1918, the disease was named “Spanish flu” or “La Grippe.” The initial outbreak in the United States occurred at a Kansas army camp in March 1918. Like many viral respiratory diseases, Spanish flu subsided with the onset of summer. Only isolated cases were identified over the next few months.
The disease reemerged with explosive force in the autumn of 1918. The first major outbreaks in the United States occurred in Boston, MA, and Philadelphia, PA. By the time the Spanish flu ran its course, more than 25% of the US population had fallen ill, and 675,000 Americans had died. Worldwide, Spanish flu killed at least 20 million people, making it the most deadly global pandemic in history.16, 17
With an estimated case-fatality rate of 2.5%, Spanish flu was 25 times more deadly than a typical outbreak of influenza, which kills only one tenth of 1% of infected individuals.11 SARS is less contagious than influenza, but it is readily transmitted to close contacts, including health care workers wearing personal protective equipment.18 More disturbingly, SARS is more virulent than any known strain of influenza, including the Spanish flu of 1918.
If SARS returns this winter, or at any time in the future, it could pose an enormous threat to the US public. If past experience is any predictor of future events, the disease will strike with particular force at health care workers who provide “first contact” care to acutely ill patients, namely, providers of emergency medical services (EMS) and hospital emergency department (ED) staff. For various reasons, these individuals are already stretched to their operating limits.19, 20
When SARS was first identified, US hospitals were able to screen ED patients by asking those with acute respiratory symptoms and fever if they had a history of recent travel to a SARS-endemic area or contact with someone from an endemic area. This strategy worked because SARS was entering the United States from a relatively small number of Asian countries and the city of Toronto. If SARS ever becomes established in the United States, these questions will lose their specificity. Once that happens, it will be extremely difficult to differentiate early cases of SARS from the broad variety of respiratory illnesses that cause fever, cough, and myalgias.21, 22 In a normal fall or winter, millions of Americans experience these symptoms.
If and when SARS returns, protecting our nation's health care workers should be a top priority. EMS and hospital employees were heavily represented among the early victims of the first SARS outbreaks. Several became “superspreaders” of infection to other patients, fellow health care workers, and close family contacts. Once news of these cases surfaced, many health care workers, including those who were neither infected nor placed in quarantine, reported that other members of the community avoided them.18, 23 As fellow staff members fell ill or were quarantined, those that remained were forced to work long hours in uncomfortable personal protective equipment. Changing directives over use of protective gear heightened fears of occupational infection. These factors placed health care workers in affected cities under tremendous physical and emotional stress.18, 23
To avoid a replay of problems encountered around the globe, immediate steps should be taken to enhance the nation's capacity to control this highly lethal disease. There are many reasons to do so above and beyond betting on whether SARS will ever return. SARS resulted from a confluence of natural events,24, 25 but it shares many characteristics with bioterrorism agents (Table). Therefore, rapid adoption of processes and procedures to safely identify and control SARS will not only safeguard public health, they will enhance national security.26, 27
Ironically, despite ongoing fear of bioterrorism, it can be argued that key elements of our health care system today are less capable today of containing a biologic threat than they were before September 11, 2001.19, 20, 27 There are many explanations for this paradox. As a result of progressive cuts in third-party reimbursement and a shortage of trained staff, US hospitals shed 103,000 staffed hospital beds and 7,800 medical/surgical ICU beds during the decade of the 1990s.28 Fewer beds mean longer waits before unscheduled admissions from the EDs can reach an inpatient unit.19, 20 Boarding of admitted patients in the ED is the factor most commonly associated with crowded conditions and subsequent diversion of inbound ambulances—practices that heighten the risk of disease transmission. These are more than theoretical concerns. When the second victim of SARS in Toronto presented to a hospital for treatment of what was thought at the time to be “community acquired pneumonia,” he was held in the ED for a protracted period of time until an inpatient bed became available.29 During his lengthy ED stay, he infected several patients and members of the hospital staff, some of whom subsequently died. The Toronto outbreak ultimately cost the Canadian economy more than $1.3 billion dollars.
This is why the articles in this issue of Annals are so important.30, 31, 32, 33, 34 Observations gleaned from the initial outbreaks of SARS may offer important insights into what we can do to effectively contain a future outbreak of this deadly disease. Although this information will be helpful, it will do little good unless policymakers recognize the need to take immediate steps to provide our nation's EMS systems, EDs, and hospitals with the protective equipment, training, and facilities they need to safeguard the public's health. Most of the funds that were publicly pledged to strengthening the nation's defenses against bioterrorism have not yet reached their target groups. As a result, we are woefully unprepared for a reemergence of SARS this winter.
Considering the nationwide shortage of nurses and other skilled health care workers, protecting our health care workforce must be a top priority. This entails immediate provision of training and decision support systems, rapid distribution of personal protective equipment, and rigorous oversight of infection control measures. Failure to adopt these measures may result in the widespread occupational exposure and subsequent quarantine of large numbers of health care workers. This would devastate the staffing plans of hospitals and EMS services at the outset of an epidemic, precisely when these personnel are most needed.
Likewise, a major outbreak of SARS in the United States will disrupt the day-to-day care that consumes most hospitals. It could even incapacitate multiple hospital campuses. This occurred in Canada and China.8, 29 If even one hospital becomes contaminated with SARS, subsequent decontamination will be costly and time-consuming. Given evidence that the number of inpatient beds in many large metropolitan areas is inadequate to meet the needs of the community, the loss of even a single hospital would be a matter of grave concern.
If SARS has been stopped “dead in its tracks,” as some assert, these worries are moot.5 If, however, the world has been granted little more than a seasonal respite, we have scant time to prepare. The measures needed to promptly identify and control the next outbreak of SARS are the same ones needed to control the next pandemic strain of influenza or the intentional release of a bioterrorism agent. They should be adopted as quickly as possible.
Footnotes
Editor's note: This article was first published on Annals' Web site (www.mosby.com/AnnEmergMed) on December 2, 2003. Articles of particular interest are published on the Web site in advance of their appearance in the print journal. In the future, an increasing percentage of our content will be published first on the Web, predating the print publication as a service to our readers.
The authors report this study did not receive any outside funding or support.
References
References
- 1.Booth CM, Matukas LM, Tomlinson GA. Clinical features and short-term outcomes of 144 patients with SARS in the greater Toronto area. JAMA. 2003;289:2801–2809. doi: 10.1001/jama.289.21.JOC30885. [DOI] [PubMed] [Google Scholar]
- 2.Poutanen SM, Low DE, Henry B. Identification of severe acute respiratory syndrome in Canada. N Engl J Med. 2003;348:1995–2005. doi: 10.1056/NEJMoa030634. [DOI] [PubMed] [Google Scholar]
- 3.Lee N, Hui D, Wu A. A major outbreak of severe acute respiratory syndrome in Hong Kong. N Engl J Med. 2003;348:1986–1994. doi: 10.1056/NEJMoa030685. [DOI] [PubMed] [Google Scholar]
- 4.Gerberding JL. Fasterébut fast enough? Responding to the epidemic of severe acute respiratory syndrome. N Engl J Med. 2003;348:2030–2031. doi: 10.1056/NEJMe030067. [DOI] [PubMed] [Google Scholar]
- 5.Sternberg S. Experts: SARS Is stopped. USA Today. June 18, 2003:1A. [Google Scholar]
- 6.Connolly C. Doctor says worst of SARS to come. Atlanta Journal Constitution. May 22, 2003:B4. [Google Scholar]
- 7.Drazen JM. Case clusters of the severe acute respiratory syndrome. N Engl J Med. 2003;348:e6–e7. doi: 10.1056/NEJMe030062. [DOI] [PubMed] [Google Scholar]
- 8.Tsang KW, Ho PL, Ooi GC. A cluster of cases of severe acute respiratory syndrome in Hong Kong. N Engl J Med. 2003;348:1977–1985. doi: 10.1056/NEJMoa030666. [DOI] [PubMed] [Google Scholar]
- 9.Update: Outbreak of SARS—Worldwide, 2003MMWR Morb Mortal Wkly Rep. 2003;52:241. [PubMed] [Google Scholar]
- 10.Update: SARS—United StatesMMWR Morb Mortal Wkly Rep. 2003;52:525–526. [PubMed] [Google Scholar]
- 11.Beckley E. When SARS soars: CDC warns of larger outbreaks of the infection. Modern Physician. 2003;7:10. [Google Scholar]
- 12.Lew T, Tong-Kiat K, Tai D. Acute respiratory distress syndrome in critically ill patients with severe acute respiratory syndrome. JAMA. 2003;290:374–380. doi: 10.1001/jama.290.3.374. [DOI] [PubMed] [Google Scholar]
- 13.Fowler RA, Lapinsky SE, Halley D. Critically ill patients with severe acute respiratory syndrome. JAMA. 2003;290:367–373. doi: 10.1001/jama.290.3.367. [DOI] [PubMed] [Google Scholar]
- 14.Reilly B, Van Herp M, Sermand D. SARS and Carlo Urbani. N Engl J Med. 2003;348:1951–1952. doi: 10.1056/NEJMp030080. [DOI] [PubMed] [Google Scholar]
- 15.Rubenfield GD. Is SARS just ARDS? JAMA. 2003;290:397–399. doi: 10.1001/jama.290.3.397-a. [DOI] [PubMed] [Google Scholar]
- 16.Stanford University Web site. The influenza pandemic of 1918. Available at: http://www.stanford.edu/group/virus/uda. Accessed November 20, 2003.
- 17.Crosby A. America's Forgotten Pandemic: The Influenza of 1918. Cambridge University Press; Cambridge, United Kingdom: 1989. pp. 1–69. [Google Scholar]
- 18.Maunder R, Hunter J, Vincent L. The immediate psychological and occupational impact of the 2003 SARS outbreak in a teaching hospital. CMAJ. 2003;168:1245–1251. [PMC free article] [PubMed] [Google Scholar]
- 19.The Lewin Group . Emergency Department Overload: A Growing Crisis. Results of the AHA Survey of ED and Hospital Capacity. AHA Publications; Chicago, IL: 2003. [Google Scholar]
- 20.General Accounting Office . Hospital Emergency Departments: Crowding Conditions Vary Among Hospitals and Communities. GAO-03-460. General Accounting Office; Washington DC: March 2003. [Google Scholar]
- 21.Masur H, Emanuel E, Lane HC. Severe acute respiratory syndrome: providing care in the face of uncertainty. JAMA. 2003;289:2861–2863. doi: 10.1001/jama.289.21.JED30036. [DOI] [PubMed] [Google Scholar]
- 22.Wenzel RP, Edmond MB. Managing SARS amidst uncertainty. N Engl J Med. 2003;348:1947–1948. doi: 10.1056/NEJMp030072. [DOI] [PubMed] [Google Scholar]
- 23.Cameron PA, Rainer TH. Commentary: update: outbreak of severe acute respiratory syndrome—worldwide, 2003. Ann Emerg Med. 2003;42:110–116. doi: 10.1067/mem.2003.318. [DOI] [PMC free article] [PubMed] [Google Scholar]
- 24.Ksiazek TG, Erdman D, Goldsmith CS. A novel coronavirus associated with severe acute respiratory syndrome. N Engl J Med. 2003;348:1953–1966. doi: 10.1056/NEJMoa030781. [DOI] [PubMed] [Google Scholar]
- 25.Drosten C, Gÿnther S, Preiser W. Identification of a novel coronavirus in patients with severe acute respiratory syndrome. N Engl J Med. 2003;348:1967–1976. doi: 10.1056/NEJMoa030747. [DOI] [PubMed] [Google Scholar]
- 26.McNutt SD, Becher SM, Franz DR. Bioterrorism and the emergency physician: on the front lines. Emerg Med Practice. 2003;4:1–24. [Google Scholar]
- 27.Manning A. SARS: in crisis mode. USA Today. April 10, 2003:D1–D2. [Google Scholar]
- 28.Emergency departments: an essential access point to careAHA Trendwatch. 2001;3:1–8. [Google Scholar]
- 29.Donovan K. How world let virus spread. Toronto Star. April 19, 2003:1. [Google Scholar]
- 30.Chen S-Y, Su C-P, Ma MH-M. Predictive model of diagnosing probable cases of severe acute respiratory syndrome in febrile patients with exposure risk. Ann Emerg Med. 2004;43:1–5. doi: 10.1016/S0196-0644(03)00817-5. [DOI] [PMC free article] [PubMed] [Google Scholar]
- 31.Tham K-Y. An emergency department response to severe acute respiratory syndrome: a prototype response to bioterrorism. Ann Emerg Med. 2004;43:6–14. doi: 10.1016/j.annemergmed.2003.08.005. [DOI] [PMC free article] [PubMed] [Google Scholar]
- 32.Wang T-L, Jang T-N, Huang C-H. Establishing a clinical decision rule of severe acute respiratory syndrome at the emergency department. Ann Emerg Med. 2004;43:17–22. doi: 10.1016/j.annemergmed.2003.08.002. [DOI] [PMC free article] [PubMed] [Google Scholar]
- 33.Chen S-Y, Chiang W-C, Ma MH-M. Sequential symptomatic analysis in probably severe acute respiratory syndrome cases. Ann Emerg Med. 2004;43:27–33. doi: 10.1016/j.annemergmed.2003.10.010. [DOI] [PMC free article] [PubMed] [Google Scholar]
- 34.Su C-P, Chiang W-C, Ma MH-M. Validation of a novel severe acute respiratory syndrome scoring system. Ann Emerg Med. 2004;43:34–42. doi: 10.1016/j.annemergmed.2003.10.042. [DOI] [PMC free article] [PubMed] [Google Scholar]