11:680:390 Lecture Notes - Lecture 25: Viral Hemorrhagic Fever, Lassa Virus, Zoonosis
27 Apr 2018
School
Department
Course
Professor
25: Soil and Vectorborne
I. Animal-transmitted Viral Disease
A. Zoonosis: animal disease transmissible to humans
1. Wild animals are a reservoir for disease (because they’re not treated by
vets or immunized)
2. Transmitted via direct contact, aerosols, bites
3. Examples: rabies, zika, malaria, lyme disease
B. Rabies Virus and Rabies
1. Occurs as an epizootic disease in animals, but can be spread as a
zoonotic disease to humans and can spread from wild animals → pets →
humans
2. Reservoirs: raccoons, skunks, coyotes, foxes, bats
3. Symptoms and Pathology
a) Rhabdovirus
(1) Negative-strand RNA virus
(2) Infects central nervous system of warm-blooded animals
(3) Enters the body through a wound or bite
(4) Leads to death if not treated
b) Virus proliferates in brain and leads to fever, excitation, dilation of
pupils, salivation, anxiety, fear of swallowing
c) Control: vaccines animal population by putting it in food
C. Hantavirus Syndrome
1. Can cause hantavirus pulmonary syndrome (HPS) and hemorrhagic fever
with renal syndrome (HFRS)
2. Caused by infected rodents
3. Transmission: inhalation of virus-contaminated rodent excreta
a) No virus-specific treatment because it’s rare/uncommon
4. Symptoms and Pathology
a) Hantavirus
(1) Enveloped, segmented, negative-strand RNA virus
(2) Related to hemorrhagic fever viruses such as Lassa virus
and Ebola virus
b) Characterized by sudden onset of fever, myalgia, and respiratory
issues
5. Epidemiology, Diagnosis, Prevention
a) Infect rodents including mice, rates, voles, lemmings
b) Up to 200,000 cases are recognized annually; this number can be
reduced by limiting mouse habitats and contact with mice and their
urine
D. Lyme Disease & Borrelia
- most prevalent tick borne disease in the US; affects
humans and other animals
1. Caused by the spirochete Borrelia burgdorferi
(deer tick)
2. Transmission: transmitted to humans while tick is obtaining blood meal
3. Pathology, Diagnosis, Treatment
