Arena Viruses
Hugh B Fackrell
Filename: Arena.ppt
4/13/2015
1
Arena Viruses
Structure
 Classification
 Multiplication
 Clinical manifestations
 Epidemiology
 Diagnosis
 Control

4/13/2015
Baron’s Web Site
2
EM of Arenavirus

Pleomorphic
– 120 nm

“Sandy”
– dense 20 nm
particles
4/13/2015
3
Structure of Arenavirus
Enveloped
 RNA

– linear or circular
– 2 strands
– negative strands
4/13/2015
4
Virus RNA transcriptase
- ss RNA
+ mRNA
+ ssRNA
Arena Virus Replication
4/13/2015
5
Reservoir
Pet hamsters
 Rodent breeding facilities
 Wild Rodents
 Virus spread from rodents by urine
and feces.

– contaminate food or water.

rodents do not acquire disease
4/13/2015
6
Arena in Humans
humans are an accidental host.
 aerosol transmission is suspected in human to
human.
 human transmission occurs because the
virulence of the virus has been increased due
to the multiplication in a human host.
 sudden eruption of the disease is due to the
lack of exposure.
 disease is acute in humans.

4/13/2015
7
Diseases
Lymphocytic choriomeningitis
 Argentinean Hemorrhagic
fever
 Bolivian Hemorrhagic fever
 Lassa Fever

4/13/2015
CDC Arenavirus factsheet
8
Lymphocytic
Choriomeningitis Virus
found in house mice - world wide.
 incubation 10-14 days.
 most asymptomatic or have mild “cold”
symptoms. More severe headache,
confusion, photophobia, listlessness,
apathy, may have more severe
neurological symptoms. In all cases the
disease is short lived and not fatal.

4/13/2015
9
Hemorrhagic Fevers
much more severe and often fatal.
 incubation 10-14 days.
 2-4 days increasing fever - progressive
malaise.

4/13/2015
10
Argentinian Hemorrhagic Fever
causes mild hepatitis
 farm workers at risk.
 death rate is 15-20%.

4/13/2015
11
Bolivian Hemorrhagic Fever
causes mild hepatitis
 farmworkers at risk.
 death rate is 15-20%.

4/13/2015
12
Lassa Fever
discovered in Nigeria, Africa.
 found in wild rodents in Nigeria, Liberia and
Sierra Leone.

4/13/2015
13
Lassa Fever Symptoms
the most serious of the four human
arenavirus infections.
 mild cases survive and may go
undetected.
 causes severe hepatitis
 Hemoconcentration and elevated SGOT
levels usually mean death.
 The death rate among severe cases is
30-60%.

4/13/2015
14
Index case
reported in a nurse.
 highly infectious. Two attending nurses
contracted the disease. One recovered,
the second was saved by the passive
transfer of the antibodies of the one
who recovered.

4/13/2015
15
DONE!!!
4/13/2015
16