protection should be worn and an impermeable gown, face shield, and gloves utilized. Patients
should be placed in a negative pressure room with 6 (old standard) to 12 (standard for new
construction) air exchanges per hour. Antiviral chemoprophylaxis should be made available to
caregivers and family members (54).
Clinical disease: There are no clinical or laboratory findings that distinguish avian
influenza from other influenza-like illnesses, severe CAP, or ARDS. In naturally occurring
disease, only epidemiology hints at the diagnosis (101).
Upon presentation, the mean temperature was 37.8 8 C (35.8 8 Cto40 8 C). Patients were
frequently hypotensive and tachypneic (average 35/min: range 15–60/min). Over 90% of
patients had either bronchopneumonia or lobar pneumonia. Approximately 15% of patients
had pleural effusions. Most patients were young adults. Mortality was approximately 60% to
80% (37,54,101,102). Patients succumb between 4 and 30 days after the onset of symptoms
(median: 8 to 23 days) (101). Aerosol-generating procedures should be minimized.
Postmortem examinations reveal disseminated intravascular coagulation (DIC), lym-
phoid necrosis and atrophy, and diffuse alveolar and multiorgan damage.
Diagnosis: Rapid diagnosis by antigen detection or reverse-transcription polymerase
chain reaction can be performed on throat swabs or nasopharyngeal aspirates in viral transport
media. Antigen detection is accomplished by indirect immunofluorescence, enzyme immuno-
assays, or rapid immunochromatographic assays. Sensitivity of kits appears to be 33.3% to
85.7% (54).
Differential diagnosis: Other forms of CAP.
Treatment: Oseltamivir is the drug of choice (75 mg PO b.i.d.) (37,101).
SARS and SARS-Associated Coronavirus (103–117)
SARS is caused by a coronavirus (a large enveloped positive-stranded RNA virus) that has
been isolated from live animal market Himalayan palm civets and raccoon dogs, bats, and
other animals (Chinese ferret bagger, domestic cats, and pigs). Rats have been experimentally
infected and may have been responsible for an outbreak in an apartment complex (103).
From November 1, 2002, through July 31, 2003, there were 8098 SARS cases reported
from 29 countries, with 774 deaths (9.6%). Of those cases, 1701 health care workers were
infected (21% of cases) (104).
Incubation period: Incubation periods have varied depending upon the site of the outbreak
(2–16 days, 2–11 days, 3–10 days) (105).
Contagious period: Historically, health care settings were important in the early spread of
SARS. The risk posed by individual patients is variable. Unrecognized SARS patients were the
primary source of contagion (106). Isolation (in a negative-pressure room) should be
maintained throughout the course of the patient’s illness. Infection control recommendations
are complex and outlined by Levy et al. (107). SARS coronavirus may be detected in stools for
as long as nine weeks (108).
Clinical disease: The severity of clinical disease appears to be related to age and genetic
factors (IL-12 RB1 variants, manose-binding lectin polymorphisms, OAS1, MxA gene,
interferon gamma gene, RANTES gene, and ICAAM3 gene) (109).
Fever of more than 38 8 C lasting more than 24 hours is the most frequently encountered
symptom. In general, the clinical presentation is varied and nonspecific. At presentation, of
five medical centers in Hong Kong and Canada, four reported chills and/or rigors (55–90% of
patients); all reported cough (46–100% of patients); four reported sputum production (10–20%);
two reported sore throat (20–30%); four reported dyspnea (10–80%); four reported gastroin-
testinal symptoms (15–50%—most commonly diarrhea); three reported headache (11–70%); all
reported myalgia (20–60.9%); and one reported pleurisy (30%) (105). Gastrointestinal
symptoms were prominent in U.S. cases (110).
Chest X rays may be normal early in the disease, but abnormal radiographs were present
in 78% to 100% of patients. These abnormalities consisted of unilateral disease (54.6%) or
multifocal or bilateral disease (45.4%). At one center, the 13% that had normal chest X rays, had
abnormal chest CT examinations (105).
Chest X rays in pediatric cases revealed nonspecific findings. In addition to the findings
above, peribronchial thickening, and (infrequently) pleural effusion were noted (111).
474 Cleri et al.