The sudden global emergence of Severe Acute Respiratory Syndrome (SARS) has sickened over 8,000 individuals, crippled health care delivery, and has had a devastating impact on the economy. The causative agent, a novel Coronavirus, is not previously known to cause disease in humans. Thus far, no specific treatment, vaccination or reliable and readily available diagnostic tests are available. Exactly where we are in the course of this epidemic is not yet clear.
Most infections have been acquired by close contact with a symptomatic individual. The virus has been cultured from nasopharyngeal secretions and stool, and has been shown to remain viable for several hours outside the body on plastic and other surfaces. It appears that respiratory droplets are the primary source of transmission. However, large clusters have been documented to result from nebulizer-generated aerosols and fecal-oral transmission (traced to damaged sewage system in an apartment complex).
The incubation period ranges from two to 16 days; the average is six days. Common symptoms include fever (100%), chills, rigors, myalgias, cough (>50%) and sputum, sore throat, coryza, nausea, vomiting, diarrhea (20-30%). Seventy percent of patients have moderate lymphopenia, and 45% have mild thrombocytopenia.
At the time of initial presentation, 70-80% of patients demonstrate varying patterns of air-space consolidation on CXR. Hypoxemia requiring ICU care develops in 20-30% of cases. The mortality rate appears to be dependent upon age, with an overall death rate of 14-15% and as high as 55% in those over 60 years of age.
The initial diagnosis of SARS relies on suspicion based on a patient's history. Specifically asking patients about their history of travel to affected areas, visits to an affected health care facility, or history of casual social contact with a suspected or probable case is critical.
Relying on initial symptoms alone, it is hard to differentiate SARS from any other flu-like illness. Since a reliable, rapid diagnostic test is not presently available, clinicians must rely on symptoms, signs, and exposure/travel history. Many patients develop an ARDS-like clinical picture. Suspect cases should receive a chest x-ray, pulse oximetry, and blood cultures. Gram stain of sputum and testing for other respiratory viruses such as influenza should be performed.
RT-PCR can rapidly document the presence of coronavirus RNA. Antibody response is now known to develop over time in serum; however, the sensitivity and specificity of these tests has not yet been established. Specimens from suspect cases should be saved for further testing, and acute and convalescent serum samples should be obtained from individuals who meet the SARS case definition (see Table 1).
|Table 1: SARS Case Definition|
Severe Respiratory Illness
- Temperature of >100.4° F (>38° C), and
- One or more clinical findings of respiratory illness (e.g., cough, shortness of breath, difficulty breathing, or hypoxia), and
- radiographic evidence of pneumonia, or
- respiratory distress syndrome, or
- autopsy findings consistent with pneumonia or respiratory distress syndrome without an identifiable cause.
* Close contact is defined as having cared for or lived with a person known to have SARS or having a high likelihood of direct contact with respiratory secretions and/or body fluids of a patient known to have SARS. Examples of close contact include kissing or embracing, sharing eating or drinking utensils, close conversation (<3 feet), physical examination, and any other direct physical contact between persons. Close contact does not include activities such as walking by a person or sitting across a waiting room or office for a brief period of time.
- Travel (including transit in an airport) within 10 days of onset of symptoms to an area with current or previously documented or suspected community transmission of SARS, or
- Close contact* within 10 days of onset of symptoms with a person known or suspected to have SARS.
Appropriate precautions need to be taken while evaluating suspected patients, starting from the point of triage. Patients with suspicious symptoms should be provided with a surgical mask upon arrival. When possible, suspect cases should be evaluated in a designated area.
Control of the epidemic relies on quarantining exposed individuals and tracing their contacts. Institutionalized individuals who may have been exposed, and their caretakers, should have their temperature checked regularly.
Clinicians and others who work in health care settings need to adhere to strict respiratory and contact precautions. All individuals should undergo mask fit testing. Staff need to learn the proper methods for putting on, removing, and disposing of personal protection gear. Those evaluating suspect cases should use standard precautions (hand washing), airborne precautions (N-95 respirator), and contact precautions (gowns and gloves). Hospital disinfectants including those based on quaternary ammonium, phenol and alcohol, are highly active against coronaviruses.
During an outbreak, patients and caretakers should remain separated from others in order to minimize the chance of spread to other patients and health care workers. Also, the number of social visitors into the facility needs to be restricted, elective procedures should be delayed, and the number of staff caring for SARS patients should be limited.
SARS in the United States
In the United States SARS has occurred in people with a history of travel to countries with SARS. In the U.S., casual contact with SARS patients has not resulted in transmission of the causative virus. Efforts to prevent SARS in this country have focused primarily on screening for illness in those arriving from areas with high rates of SARS. At this time, the Centers for Disease Control and Prevention (CDC) does not recommend quarantine of persons arriving from areas with SARS.
Currently, those of us working in correctional facilities might feel somewhat protected from the SARS epidemic. However, many believe that this virus will continue to circulate, and that the number of cases (including those in the U.S.) will increase. Respiratory viruses such as influenza tend to wane in the warmer months and return with the colder weather. The Directors of the National Institutes of Allergy and Infectious Diseases (NIAID) and the CDC have stated that they believe that SARS will persist and amplify in the years to come.
If this scenario unfolds, management of patients presenting with what appears to be a routine viral syndrome or community-acquired pneumonia will become much more problematic. Even now, the staff and visitors of correctional facilities are a potential source for the introduction of SARS into a jail or prison. One can easily imagine how rapidly this illness might overwhelm a vulnerable population crowded together in a congregate living environment.
Implementing a Plan
The worldwide experience with SARS has allowed us to strategize for the likely eventuality of SARS in our practice settings. The following questions should be kept in mind while preparing a plan to manage SARS in the correctional setting.
- Can you obtain enough masks for all patients and staff who may need them?
- Do you have the ability to do fit testing?
- Can you isolate (or at a minimum cohort) all suspect cases?
- Is custodial staff prepared to control inmate movement?
- Do you have adequate contracts with outside agencies to provide appropriate medical services?
- Will you be able to feed inmates and continue other necessary programs in the event of controlled movement?
- Do you have enough health care staff to ensure the provision of necessary services in the event of an outbreak?
Bhupinder Mann, M.D., is a Mayo Clinic-trained hematologist/oncologist who spent several years working in correctional health at the California Medical Facility in Vacaville, CA. Dr. Mann is currently a Senior Consultant in Medical Oncology at the National Cancer Centre of Singapore, and has firsthand experience with the SARS epidemic. They have nothing to disclose.
Back to the HEPP Report June 2003 contents page.