3. INTRODUCTION
It is one of the most significant disease of zoonotic importance.
Rabies is an acute, viral encephalomyelitis (inflammation of both
brain and spinal cord), which affects all warm-blooded animals,
including humans.
It is a highly fatal disease, mortality rate being close to 100%.
HISTORY OF RABIES :
Man described the rabies virus in 2300 BC
The origin “rabhas” meaning to violence , which is defined at
shanskrit dating 3000BC
7. PUBLIC HEALTH SIGNIFICANCE
Epidemiology :
87 countries contain Rabies, but more cases are reported in Asia.
In Indo-Pakistan rabies is a major public health problem mainly due
to presence of a large no: of stray dogs.
More than 30,000 people died of Rabies every year in Asia.
Every year 10 million people require treatment and protection from
Rabies which is
great Financial loss.
8. PUBLIC HEALTH SIGNIFICANCE
CONT.
According to recent studies in every 8 minutes a person dies
because of rabies .
According to a survey conducted by the World Health Organization in
1987, dogs were responsible for 91 % of all human rabies cases; cats
2%; other domestic animals 3%; bat 2%; foxes 1%; and all other wild
animals, Iess than 1 %.
The prime importance of rabies is its transmissibility to humans with
veterinarians being at special risk
9. PUBLIC HEALTH SIGNIFICANCE
CONT.
Rabies is the 10th biggest cause of death due to infectious diseases
worldwide [1].
It is estimated that 2.5 billion people across 100 countries are at risk
of contracting rabies .
The annual death toll is around 50 000–60 000, with 99% occurring in
tropical developing countries .
Around 36% of these rabies related deaths occur in India every year
with dog bites being responsible for 95-97% of these cases
Across Asia the annual expenditure due to rabies is estimated to be
reaching 563 million USD
10. ETIOLOGY
It is viral borne disease .
Rabies virus—a single-stranded, enveloped, bullet-shaped RNA virus; genus
Lyssavirus; family Rhabdoviridae.
Lyssavirus of rabies is truly neurotropic and causes lesions only in nervous
tissue.
It is one of the larger viruses (180 nm long and 80 nm wide), and
is relatively fragile. It is susceptible to most disinfectants, and dies in dried
saliva in a few hours.
11.
12.
13. SOURCE OF INFECTION
SOURCES OF INFECTION ARE:
Scratch from infected animal
Bites from infected animal
Bat saliva In air
14. MODE OF TRANSMISSION
The rabies virus is readily transmitted between mammals, whether they
are the same or different species.
This virus is usually spread in the saliva, when an infected
animal bites another.
Rarely , an animal or person is infected by contact with infectious saliva or
neurological tissues, through mucous membranes or breaks in the skin.
Aerosol transmission is documented in laboratories and bat caves where
there is high concentration of virus in air.
Cases of transmission from unpasteurized milk from rabid animal is also
seen.
15.
16. SIGNS AND SYMPTOMS
Signs in case of Dogs :
Three progressive stages of disease—
prodromal; furious; and paralytic form and in case of cats 90% is furious
form.
The paralytic (“dumb”) form of rabies is characterized by :
1. progressive paralysis. In this form, the throat and
masseter muscles become paralyzed; the animal may be
unable to swallow and it can salivate profusely.
2. There may be facial paralysis or the lower jaw may drop.
3. Ataxia, incoordination and ascending spinal paresis or paralysis are also
typical of
this form.
4. Death usually occurs within 2 to 6 days, as the result of respiratory
failure.
5. These animals are not vicious, and rarely attempt to bite .
17. FURIOUS FORM :
In the "furious form", the animal becomes irrational and viciously
aggressive. This form is the classical "mad-dog syndrome".
The animal goes into rages (violent anger), biting and slashing at any
moving object or even inanimate objects, such as sticks and trees.
The furious champing of the jaws (i.e., chewing noisely) is
accompanied by excessive salivation.
18.
19.
20. RABIES IN CATTLE
Clinical signs are variable and can include anorexia, pruritis , ataxia,
lameness, tenesmus, hypersalivation, and aggression.
Rabid cattle may appear to be choking which prompts owners, and
veterinarians, to insert a hand into the mouth in an attempt to
remove a foreign body.
Distinct vocalization, bellowing, that some veterinarians say is
specific to rabies is a common sign.
Rabies should be on the differential diagnosis list for cattle that
exhibit abnormal behavior, inability to swallow or choke, neurological
abnormalities, and lameness.
21. SYMPTOMS IN OTHER ANIMALS
Sheep and goat :
Typical symptoms include difficulty swallowing.
Excessive salivating.
Abnormal behavior.
Lethargy and lying down.
Tremors and other neurological symptoms
Finally paralysis.
22. In PIGS as follow :
Nervous twitching of the face muscles.
Fits and convulsions.
Rapid chewing.
Salivation.
The muscles may also go into spasm.
Posterior paralysis may occur.
Death usually takes place within 3 days
24. SIGN AND SYMPTOMS IN HUMAN
The early symptoms may include nonspecific:
prodromal signs such as
1. malaise,
2. fever or headache,
3. well as discomfort,
4. Pain
5. pruritus or sensory alterations at
the site of virus entry.
25. LATER STAGE
After several days:
1. Anxiety, confusion and agitation may appear, and progress to
insomnia
2. Abnormal behavior, hypersensitivity to light and sound
3. Delirium, hallucinations, slight or partial paralysis
4. Hypersalivation, difficulty swallowing, pharyngeal spasms
upon exposure to liquids, and convulsions.
5. Either an encephalitic (furious) form with hyperexcitability,
autonomic dysfunction and hydrophobia, or a paralytic
(dumb) form characterized by generalized paralysis, may
predominate.
6. Death usually occurs within 2 to 10 days; survival is extremely rare
26. TREATMENT FOR HUMANS
Postexposure prophylaxis consists of immediate wound cleansing and
disinfection, followed by rabies vaccination and the administration of
human rabies immunoglobulin.
The rabies vaccine is given as 5 doses and it is usually administered
intramuscularly in the arm.
Fewer doses and no rabies immunoglobulin are given if the person was
previously vaccinated.
There is no effective treatment once the symptoms develop.
27. WHAT TO DO WHEN UNIDENTIFIED
DOG BITE ?
Asymptomatic dogs or unidentified cats or ferrets that have
bitten
humans (with no history of exposure to rabies) are currently
observed for 10 days
If the animal develops the signs of rabies during this time, it is
euthanized and tested for rabies and treatment is done
accordingly
28. DIAGNOSIS
Diagnosis plays a major role in the process of disease treatment and
prevention .
Rabies could be diagnosed with the help of clinical signs and
symptoms as discussed like paralytic and furious form.
Different form of diagnosis are as :
1 )A fluorescent antibody test (FAT) on impression smears from the
brain,
preferably hippocampus, medulla 0 blongata, cerebellum 0 r
gasserian g anglion. The test can be completed in about 2 hours and
is highly accurate.
2) A histological search of Negri bodies in tissue sections with results
available in 48 hours. However, the Iimitation of t his technique is
that the
brains of as many as 30% of infected animals may not contain
demonstrable
Negri bodies.
29. DIAGNOSIS CONT.
Those specimens which are negative on F AT, and had contacts
with
humans, are inoculated into experimental mice.
Mice of all ages are susceptible to rabies virus, but newborn
mice less than 3 days of age are most sensitive.
Following intracerebral inoculation, newborn mice usually die
within
14 days, but should be examined daily for at least 4 weeks
before the test is
considered negative.
30. PREVENTION AND CONTROL
1. Rabies can be prevented in domesticated animals by vaccination and by
the avoidance of contact with rabid wild animals.
2. Rabies vaccines are available for dogs, cats, ferrets, cattle, sheep and
horses.
Both inactivated and modified live vaccines are effective, but rare cases
ofpost-vaccinal rabies have been reported with the modified live
vaccines in dogs and cats.
3. Wild animals can be immunized with oral vaccines distributed in bait.
4. Preventing animals from roaming will reduce the risk of exposure to
rabid wild animals. To protect pet rabbits and rodents, they should be
housed indoors, and watched closely
33. PREVENTION AND CONTROL CONT.
As much as possible, domesticated animals should be kept away from
contact with wildlife, especially those that behave unusually. Bats caught by
cats should be submitted for rabies testing.
To prevent the transmission of rabies to humans or other animals (as well
as to prevent unnecessary prophylaxis in people who have been exposed),
unvaccinated animals that have been exposed should be
euthanized and tested.
34. NEW APPROACHES ?
According to recent studies conducted in India they found that
Animal Birth Control programs which are conducted by different local
and international organization has significantly reduced the number
of cases of rabies in state of GOA .
Castration and Spaying along with vaccination and tagging of stray
and wild dog is being done in GOA state and it has given the positive
response towards the reducing the number of cases .
35. REFERENCES
Baxter J. M. (2012). One in a million, or one in thousand: What is the
morbidity of rabies in India?. Journal of global health, 2(1), 010303.
doi:10.7189/jogh.02.010303
Centers for Disease Control and Prevention (CDC)
http://www.cdc.gov/rabies/m
Compendium of Animal Rabies Prevention and Control
http://www.cdc.gov/mmwr/pdf/rr/rr5702.pdf
International Veterinary Information Service (IVIS) http://www.ivis.org
Medical Microbiology http://www.gsbs.utmb.edu/microbook
36. Public Health Agency of Canada. Material Safety Data Sheets
http://www.phac-aspc.gc.ca/msds-ftss/index.html
The Merck Manual http://www.merck.com/pubs/mmanual/
The Merck Veterinary Manual
http://www.merckvetmanual.com/mvm/index.jsp
