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Zoonotic Disease Considerations
Japanese encephalitis
Agent: Japanese encephalitis virus (flavivirus)
Principal Animal Hosts: Horses, swine, wild birds
Clinical Disease in Animals: Abortion in swine - teratogenic, hydrocephalus; stillbirth, mummification,
embryonic death, and infertility (SMEDI)
Probable Mode of Transmission: Bites of mosquitoes (Culex spp)
Known Distribution: Asia, Pacific islands from Japan to the Philippines
ID: Viral Gastroenteritis (intestinal flu) See Symptom: Diarrhea.
ID: Hantavirus
COL Naomi Aronson, MC, USAIntroduction: Hantaviruses infect rodents worldwide and aerosolization of rodent excreta (especially urine)
is responsible for transmitting infection. There are many hantaviruses, with the most important being the
Hantaan and Seoul viruses (found in Korea, China, and far eastern Russia) which cause hemorrhagic fever
with renal syndrome (HFRS). Dobrava virus ( found in the Balkans) also causes HFRS. Puumala virus
(found in Western Europe and Scandinavia) causes a milder form of HFRS. Sin Nombre virus, mainly found
in the western U.S. and Canada, causes Hantavirus Pulmonary syndrome (HPS). The incubation period is
generally 1 to 4 weeks.
Subjective: Symptoms
HFRS:
Constitutional: Acute (1-4 days): High fever, chills, myalgias, headache; Sub-acute (5-14 days): Low
grade fever, apprehension; Chronic (> 2 weeks): Fatigue and lethargy
Specific: Acute (1-4 days): Abdominal pain, flushed face; Sub acute (5-14 days): Low urine output, back
pain; Chronic (> 2 weeks): Diuresis, renal concentrating defect
HPS:
Constitutional: Same as above
Specific: Acute (1-4 days): Dizziness, abdominal pain, diarrhea; Sub-acute (5-14 days): Dyspnea, non-
productive cough, shock
Focused History: Have you recently seen evidence of mice/rats near or in where you live or sleep? (typical
exposure) Have others in your family, village or unit had similar symptoms? (outbreaks occur in others
similarly exposed)
Objective: Signs
HFRS:
Using Basic Tools: Acute (1-4 days): Toxic appearance, fever to 104°F, conjunctival injection, flushed
face/neck/ upper torso (blanches with pressure), dermatographism (drawing on skin leaves an exaggerated
mark); Sub-acute (5-14 days): Temperature up to 101°F, truncal and axillary fold petechiae, lowered blood
pressure, low urine output up to day 7, profound diuresis thereafter(up to liters/day)
HPS:
Using Basic Tools: Inspection: Acute (1-4 days): Increased respiratory rate, accessory muscle use for
breathing, Fever to 104° F
Auscultation: Acute (1-4 days): Lungs often normal, tachycardia, mild hypotension; Sub acute (5-14 days):
Diffuse “Velcro” rales
Using Advanced Tools:
HFRS: Urine is dilute (specific gravity 1.010) with proteinuria, hematuria, occasional red and white blood
cell casts; may see elevated white blood count, thrombocytopenia, increased hematocrit (up to 55-65% in
severe infection).