communicable disease rabies

1. Communicable disease
RABIES
Done by: Hassenine Ali Kareem

2. Infectious agent
Rabies virus, a rhabdovirus of the genus
Lyssavirus.
All members of the genus are antigenically
related, but use of monoclonal antibodies and
nucleotide sequencing shows differences
according to animal species or geographical
location of origin.
-
Control Of Communicable Diseases Manual 18th Edition (2004
David L. Heymann, M.D.

3. Symptoms
Initial symptoms of rabies include a fever with
pain and unusual or unexplained tingling,
pricking, or burning sensation (paraesthesia) at
the wound site. As the virus spreads to the
central nervous system, progressive and fatal
inflammation of the brain and spinal cord
develops.
https://www.who.int/news-room/fact-sheets/detail/rabies

4. There are two forms of the disease
• Furious rabies results in signs of hyperactivity, excitable
behaviour, hydrophobia (fear of water) and sometimes
aerophobia (fear of drafts or of fresh air). Death occurs
after a few days due to cardio-respiratory arrest.
• Paralytic rabies accounts for about 20% of the total
number of human cases. This form of rabies runs a less
dramatic and usually longer course than the furious
form. Muscles gradually become paralyzed, starting at
the site of the bite or scratch. A coma slowly develops,
and eventually death occurs. The paralytic form of rabies
is often misdiagnosed, contributing to the under-
reporting of the disease.
https://www.who.int/news-room/fact-sheets/detail/rabies

5. https://www.quora.com/Why-does-an-individual-infected-with-rabies-starts-fearing-bright-light-and-water

6. Reservoir
Wild and domestic Canidae, including dogs, foxes,
coyotes, wolves and jackals; also skunks, racoons,
mongooses and otherbiting mammals. In
developing countries, dogs remain the principal
reservoir. Infected populations of vampire,
frugivorous and insectivorous bats occur in Mexico,
Central and South America; infected insectivorous
bats in Canada, the USA and Europe. Rabbits,
opossums, squirrels , chipmunks, rats and mice are
rarely infected

8. Post-exposure prophylaxis (PEP)
• Post-exposure prophylaxis (PEP) is the immediate
treatment of a bite victim after rabies exposure. This
prevents virus entry into the central nervous system,
which results in imminent death. PEP consists of:
• Extensive washing and local treatment of the bite
wound or scratch as soon as possible after a suspected
exposure;
• a course of potent and effective rabies vaccine that
meets WHO standards; and
• the administration of rabies immunoglobulin (RIG), if
indicated.
• Starting the treatment soon after an exposure to rabies
virus can effectively prevent the onset of symptoms
and death.
https://www.who.int/news-room/fact-sheets/detail/rabies

9. Extensive wound washing
This first-aid measure
includes immediate and
thorough flushing and
washing of the wound for
a minimum of 15 minutes
with soap and water,
detergent, povidone
iodine or other substances
that remove and kill the
rabies virus.

10. Categories of contact with suspect rabid animal
1. Category I - touching or feeding
animals, animal licks on intact
skin (no exposure)
2. Category II - nibbling of
uncovered skin, minor scratches
or abrasions without bleeding
(exposure)
3. Category III - single or multiple
transdermal bites or scratches,
contamination of mucous
membrane or broken skin with
saliva from animal licks,
exposures due to direct contact
with bats (severe exposure)
 Washing of exposed
skin surfaces, no PEP
 Wound washing and
immediate vaccination
 Wound washing,
immediate vaccination
and administration of
rabies immunoglobulin

11. Occurrence
• Worldwide, with an estimated 65 000–87 000
deaths
• a year, almost all in developing countries,
particularly Asia (an estimated38 000 to 60
000 deaths) and Africa (estimated 27 000
deaths). Most
• human deaths follow dog bites for which
adequate post-exposure prophylaxis was not
or could not be provided
-
Control Of Communicable Diseases Manual 18th Edition (2004
David L. Heymann, M.D.

12. In the above table, two cases were diagnosed with a dog from
the collection of cases that were exposed to the animal.one
cases died
sectores
august
september
october
First Hilla Sector
36
45
54
Second Hilla Sector
21
32
25
Almahaweel of
sector
50
45
42
Musayyib of sector
17
24
24
Hashemite of sector
66
59
79
In Babylonian Governorate

13. Dogs and Rabies Transmission
Worldwide >90% of rabies exposures are from
dogs
Worldwide >99% of human rabies deaths are
via dogs
 Rabies control and elimination is possible in
dogs
CDC-Rupprecht CE, et al. Devel Biol (Basel). 2008;131:95-121 14

14. Incubation period
Usually 3–8 weeks, rarely as short as 9 days or
as long as 7 years; depends on wound severity,
wound site in relation to nerve supply and
distance from the brain, amount and strain of
virus,
-
Control Of Communicable Diseases Manual 18th Edition (2004
David L. Heymann, M.D.

15. Period of communicability
In dogs and cats, usually for 3–7 days
before onset of clinical signs (rarely over 4 days)
and throughout the course of the disease. Longer
periods of excretion before onset of clinical signs
(14 days) have been observed with Ethiopian dog
rabies strains. In
one study, bats shed virus for 12 days before
evidence of illness; in another, skunks shed virus for
at least 8 days before onset of clinical signs. Skunks
may shed virus for up to 18 days before death
.
-
Control Of Communicable Diseases Manual 18th Edition (2004
David L. Heymann, M.D.

16. Susceptibility
All mammals are susceptible to varying
degrees,which may be influenced by the virus
strain. Humans are more resistant to
infection than several animal species; a study in
the Islamic Republic of Iran showed that, of
those bitten by proven rabid animals and not
treated,about 40% developed the disease
-
Control Of Communicable Diseases Manual 18th Edition (2004
David L. Heymann, M.D.

17. Rabies: Foundations of Prevention
and Control
1. Vaccination of dogs
2. Minimization of human exposures to
infected animals
3. Prompt wound care and prophylaxis with
vaccine and rabies immune globulin after
exposure
CDC-Rupprecht CE, et al. Devel Biol (Basel). 2008;131:95-121 14

18.  Education (Avoid bites but report them)
 Regulations (vaccination/importation laws)
 Quarantine
 Dog Vaccination Campaigns
 Oral Rabies Vaccination (ORV) in wildlife
 Spay/neuter/Contraception to control dog
populations
Effective and efficient diagnostics Effective
Control of Dog Rabies Integration of Tools