Rabies is an acute viral infection of the Nervous system, caused by the virus Neurotropic Lyssavirus. The virus is commonly transmitted to man through the bite of a rabid animal. More than 3.3 billon people are at risk of rabies worldwide, with approximately 55,000 deaths estimated per year. Rabies epidermis occurs in Asia with an estimated 31,000 deaths and Africa with an estimated 24,000 deaths. Rabies virus, the agent of the disease is a member of the Rhabdoviridae family (Genus: Lyssavirus). The virus travels to the brain through the peripheral nerves causing acute encephalitis (inflammation of the brain) in warm-blooded animals (man). Early symptoms associated with the virus includes Malaise, headache and fever, progressing to acute pain, restlessness, hyperactivity, uncontrolled excitement, depression, hydrophobia, etc.

1. A PRESENTATION
ON
RABIES
BY
MARTINS NELSON OSAIGBOKAN UWAMOSE
CHIEF LIBRARIAN
DEPARTMENT OF ANIMAL AND ENVIRONMENTAL BIOLOGY
FACULTY OF SCIENCE,
DELTA STATE UNIVERSITY, ABRAKA
JANUARY , 2013
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2. INTRODUCTION
 Rabies is an acute viral infection of the Nervous system caused by
Rabies virus.
 The virus is often transmitted to humans through the bite or lick of
fresh skin wound by a rabid animal (mostly dogs).
 Rabies virus, the agent of the disease is a member of the
Rhabdoviridae family (Genus: Lyssavirus); it is a single stranded,
neurotropic, negative sense RNA virus (Albertini et al., 2006).
 Rabies virus travels to the brain through the peripheral nerves
causing acute encephalitis (inflammation of the brain) followed by
paralysis and death in warm-blooded animals (man).
 The incidence of Rabies virus infection per year in the world is
estimated at 3.3 billion to 3.6 billion with approximately 55,000
death.
 Rabies epidermis occurs in Asia, North and South America, and
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Africa.

3. Fig 1. Map of the world showing the presence / absence of Rabies as at 2010
Source: World Health Organization (WHO), 2010
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4. PROPERTIES OF RABIES VIRUS
Rabies virus is bullet shaped and has a
protein coat with a lipid envelope. It’s
outer surface is covered with thumblike glycoprotein projections that are
5-10 nm long and 3 nm in diameter.
The length of the virus averages
approximately 780 nm (Albertini et
al., 2006)
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5. Fig 2. Properties of Rabies virus
Source: Albertini et al., 2006
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6. PATHOGENESIS
Rabies infection is initiated in the victim on
acquisition of the virus through the bite or direct
saliva contact with infected animal. The virus then
incubates at the site of inoculation replicating within
muscle cells. After long incubation period, the virus
enters the peripheral nerves and travels by
retrograde axonal flow towards the Central Nervous
System, first to the spinal cord then to the brain.
Once in the brain, the virus travels by axonal flow
down the trigemmal nerve to the salivary glands. The
virus is found in the saliva (Drew WL, 2004, Beard
M, 2001, Takayama N, 2005)
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7. EPIDEMIOLOGY/MECHANISM
Rabies virus is zoonotic, meaning it can be
transmitted from one species to another
such as dogs to humans commonly by an
infected animal. The virus is found at the
saliva of infected animals which show
clinical signs; they excrete the virus
through the saliva. Humans become
infected through direct contact with
infected animal saliva or when bitten.
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8. Fig 3a.
Fig 3b.
Fig 3. Transmission of Rabies Virus
Fig 3. Transmission of Rabies Virus
Source: Google images
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9. SYMPTOMS
It usually starts off like minor break down with symptoms
of very high fever, headache, general weakness and
discomfort.
It progresses to acute pain, restlessness, depression,
agitation, hyper salivation, increased sexual activity and
hydrophobia.
Finally, the patients may develop convulsions, muscles
paralysis starting at the site of the bite or scratch, which
will eventually leads to coma. Deaths usually occurs due to
respiratory insufficiency 10 – 14 days after the onset of
symptoms (Awoyomi et al., 2007, Takayama N 2005, Drew
WL 2004).
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10. EFFECTS OF RABIES
Rabies disease is known to affect the spinal
cord and the brain. This infection travels to
the spinal cord and then to the brain through
the peripheral nerves. Undiagnosed delayed
or untreated Rabies causes acute
encephalitis (inflammation of the brain),
damage to the nervous system, muscles
paralysis, and death (Drew WL 2004).
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11. DIAGNOSIS
A concrete diagnosis is made after
laboratory test, that isolates the virus
from the patient’s saliva or throat or
corneal impression, skin biopsies and
post-mortem
tissue
samples
by
Fluorescent Antibody Test (FAT) or by the
Avidin-Biotin technique.
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12. Fig 2. Diagnosis of Rabies virus
Source: World Health Organization (WHO), 2005
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13. TREATMENT
Treatment is by means of injections of rabies
vaccines, antiserum and immunoglobulin
which may prevent the virus from infecting if
given with in 2 days. The incubation period for
rabies enables effective treatment to be given,
but if symptoms appear, they are treated with
sedative drugs and analgesic drugs (Jackson AC
2008, DeMaria et al., 2010, Suzuki et al., 2008,
Takayama, N., 2008, Adedeji et al., 2010).
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14. PREVENTION AND CONTROL
Preventive and control measures include exposure of
vaccinated animal, immediate vaccination. Others include:
Immunize all dogs and cats owned by an individual or by the
community,
Immunize any person with proven or probable exposure to
rabies and administer rabies immunoglobulin in case of severe
exposure (WHO 2005),
Pounding and killing of stray dogs,
Wild animals should not be kept as pets,
Killing of wildlife around during an epidemic,
Humans at high risk (e.g. laboratory personnel, professions at
high risk) must receive pre-exposure immunization,
People living or travelling to countries were rabies is endemic
should be vaccinated with three doses of human diploid cell
rabies vaccine (Adedeji et al., 2010),
Strict quarantine regulations,
Lastly, oral vaccines should be given to wild animals through
bait. (WHO, 1997)
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15. CONCLUSION
Rabies is a neglected disease of the poor and vulnerable
populations whose deaths are rarely reported. It occurs
mainly in rural communities where measure to prevent dog
to human transmission have not been implemented.
Eradication of rabies should be geared towards prevention,
control and treatment. This could be achieved through health
education, improvement of quarantine regulation and human
and animal vaccination. It can be wiped out across the world
if sufficient vaccinations are carried out on domestic dogs. If
prompt medical care is available, rabies is uncommon in
human beings but remains one of the most feared diseases.
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16. THANK YOU
FOR YOUR TIME
Slide Prepared By Uwamose Martins
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