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Prevention and Hygiene: Immunize with licensed yellow fever vaccine. Booster doses are recommended
every 10 years for travel to yellow fever-endemic regions. Avoid suspected foci of yellow fever or other
hemorrhagic fevers. Practice personal protective measures against mosquitoes (see Preventive Medicine).
Follow-up Actions
Return Evaluation: Assess for onset of hemorrhagic signs, and evacuate if necessary.
Evacuation/Consultation Criteria: Urgently evacuate all suspected hemorrhagic cases (hematologic abnor-
malities, profound bleeding, or vascular instability). Consult infectious disease specialists for all cases of
hemorrhagic yellow fever, and for any cases in team members.
NOTE: Serology may be performed to confirm diagnosis and for epidemiologic case definition.
ID: Hepatitis A
LTC Duane Hospenthal, MC, USAIntroduction: Hepatitis A virus (HAV) infection is spread by fecal contamination of food or water, or by person-
to-person contact. Infection occurs worldwide with increased incidence in developing nations. Incubation
period averages 28 days. Virus is excreted into the stool of infected individuals prior to the development of
symptoms. Peak infectivity occurs two weeks prior to the development of jaundice. Most individuals recover
spontaneously and completely. No “carrier state” exists. Children can have unrecognized infection and may
shed virus for several months, making them a major source of infection to others. US service members should
be protected from infection with pre-deployment immunization.
Subjective: Symptoms
Abrupt onset fever, nausea, anorexia and malaise, often following several days of nonspecific upper
respiratory tract symptoms. Jaundice usually develops days later along with right upper quadrant abdominal
pain, dark urine, light-colored stool and pruritus.
Focused History: When did you notice you were turning yellow? (Jaundice develops several days after other
symptoms. In chronic liver disease, jaundice may develop more slowly, usually without fever or other acute
symptoms.) Is your urine darker than usual? Are your stools lighter than usual? (typical symptoms) Is anyone
else ill? (contamination from a common source) Have you injected drugs or had unprotected sex with a new
partner? (Hepatitis B, C risk factors)
Objective: Signs
Using Basic Tools: Vital signs: Low grade fever
Inspection: Jaundice of skin, sclerae, and mucous membranes under tongue
Palpation: Smooth, tender, enlarged liver edge beyond costal margin
Using Advanced Tools: Lab: Urinalysis reveals positive urobilinogen
Assessment:
Differential Diagnosis
Hepatitis B, D, and C - usually will have parenteral or sexual exposure
Hepatitis E - may not be distinguishable
Mononucleosis (Epstein-Barr virus or cytomegalovirus) - usually associated with sore throat, more severe
fever, malaise, and anorexia. May have positive Monospot
Leptospirosis - fresh water exposure, conjunctival suffusion, myalgias, more severe fever
Yellow fever - myalgia, more severe fever and malaise
Malaria - more severe, cyclic fever
Chemicals (including drugs and alcohol) - history of toxic ingestion, heavy alcohol use, no fever