1. CHARACTERISTICS
• New World hantavirus
• Family: Bunyaviridae
• Negative RNA virus
• 3-segmented genome, approx. 12kb
• Rodent-borne & zoonotic
• Direct contact or breathing in airborne particles that
come from rodent excrement, urine, saliva
• Being bitten by an infected mouse (rare)
• No vectors required for transmission
• Non-rodent species are dead ends for transmission
MUTATION RATE
• 2 × 10−6 and 3 × 10−7 substitutions/site/yr compared to
10−3 to 10−4 substitutions/site/yr of other RNA viruses
TRANSMISSION
ANIMAL RESERVOIR
• Major animal reservoir: Deer mouse, Peromyscus
maniculatus
• P. maniculatus has one of the largest geographic ranges in
North America, in most rural habitats (5)
VACCINES
Currently there are no vaccines for SNV. However,
patients who survived HPS will have life-long
immunity against SNV. No long term complications or
chronic infection were found in survived patients.
Hantavirus Pulmonary Syndrome (HPS)
Early Symptoms
(2-3 weeks after viral
infection)
Fever, headaches
Stomach problems
Muscle aches
Late Symptoms
(hours after early
symptoms)
• Shortness of breath
• Coughing
• Pulmonary edema
MORTALITY RATE
About 35-40% infected people do not survive HPS due
to severe breathing problems.
WHAT IS HPS?
HPS is a severe cardiopulmonary illness with two distinct
phases, due to infection by Sin Nombre Virus.
• Prodromal phase: share initial symptoms with other
more common viral infections
• Cardiopulmonary phase: rapid, diffuse,
noncardiogenic pulmonary edema and hemodynamic
compromise
It is a kind of disease of poverty – rural housing areas not
mouse proof.
Diameter: 120nm
Heavy snows and
rainfall in early 1993
in The Four Corners
(an area shared by
Arizona, New
Mexico, Colorado
and Utah)
More frequent
contact with
humans
More food for
deer mice led to
increased
reproduction
rates
FIRST
OUtBREAKIN
1993
TREATMENT
No specific therapy for HPS at the moment. However
early diagnosis of HPS during prodromal phase can
initiate cardiopulmonary support earlier in intensive
care unit  possibly improved survival rates.
• Oxygenation (most crucial initial treatment)
• Intubation and mechanical ventilation
• Monitoring fluid and electrolyte balances
REFERENCES
OUTBREAKS
A total of 690 cases of HPS have been reported in the
US, from 1993 onwards to January 6, 2016 (~23 years).
More recent outbreak happened in Yosemite National
Park in 2012.
1. Centers for Disease Control and Prevention. (12 January 2016) Available from: http://www.cdc.gov/ [Accessed 13 March
2016].
2. Graziano, K. L. & Tempest, B. (2002) Hantavirus pulmonary syndrome: a zebra worth knowing. American Family Physician. 66
(6), 1015-1020.
3. Ramsden, C., Melo, F. L., Figueiredo, L. M., Holmes, E. C., Zanotto, P. M. & VGDN Consortium. (2008) High rates of molecular
evolution in hantaviruses. Molecular Biology and Evolution. 25 (7), 1488-1492.
Threat Level:
ELLY LAW 00938088
Department of Life Sciences, South Kensington Campus, Imperial College London