Rabies
• Rabies is an infectious viral disease that is almost always fatal
following the onset of clinical symptoms.
• Rabies can affect both domestic and wild animals. It is spread to
people through bites or scratches, usually via saliva.
• Rabies is present on all continents, except Antarctica, with over 95%
of human deaths occurring in the Asia and Africa regions.
• Rabies is one of the neglected tropical diseases that predominantly
affects poor and vulnerable populations who live in remote rural
locations.
• RNA virus of rhabdovirus family.
• Although effective human vaccines and immunoglobulins exist for rabies, they are
not readily available or accessible to those in need.
• Treating a rabies exposure, where the average cost of rabies post-exposure
prophylaxis (PEP) is US$ 40 in Africa, and US$ 49 in Asia, can be a catastrophic
financial burden on affected families whose average daily income is around US$
1–2 per person.
• Every year, more than 29 million people worldwide receive a post-bite
vaccination. This is estimated to prevent hundreds of thousands of rabies deaths
annually
• Each year, it kills nearly 60,000 people worldwide, mostly children in developing
countries. (OIE)
• World Organization for Animal Health (OIE)
The rabies virus is a neurotropic
RNA lyssavirus (lyssa=rage), a group
of viruses responsible for causing
encephalitis
Family - Rhabdoviridae, Order
- Mononegavirales
currently 7 known genotypes of
Lyssavirus. Lyssavirus type-1 is
the classic rabies virus.
Rhabdo in Greek identifies the
characteristic bullet or rod-shape
of the viruses.
The RNA of RABV encodes 5
proteins, including the G
glycoprotein that carries the main
antigenic sites. Source: MSD Veterinary Manual
Key facts
• Rabies is a vaccine-preventable viral disease which occurs in more
than 150 countries and territories.
• Dogs are the main source of human rabies deaths, contributing up
to 99% of all rabies transmissions to humans.
• Interrupting transmission is feasible through vaccination of dogs and
prevention of dog bites.
• Infection causes tens of thousands of deaths every year, mainly in
Asia and Africa.
• 40% of people bitten by suspect rabid animals are children under 15
years of age.
• Immediate, thorough wound washing with soap and water after
contact with a suspect rabid animal is crucial and can save lives.
• WHO leads the collective “United Against Rabies” to drive progress
towards "Zero human rabies deaths by 2030".
WHO response to rabies in
Pakistan
• WHO, in collaboration with provincial health authorities, is working to
develop dog bite treatment centres to strengthen post-exposure
prophylaxis. Plans are being developed to involve other sectors, such as
livestock authorities and veterinary research centres, in rabies control.
• Main features of WHO's strategy for rabies control are:
• -mass awareness on rabies transmission, prevention and self-protection
using cost-effective methods such as local government and community
communication structures
• establishment of rabies treatment centres at each district headquarters
hospital where health-care providers will be trained on management and
treatment of dog bites with anti-rabies vaccine
• ensuring the most cost-effective and efficacious anti-rabies vaccines in
designated rabies treatment centres in all districts
• enactment and enforcement of laws relating to vaccination of pet
animals, such as dogs and cats, in order to decrease rabies incidence
among them
• creation of a mechanism to decrease the stray dog population in districts
through the use of modern methods such as bait vaccination and dog
elimination.
• development of a surveillance system to monitor dog bites, dog rabies
and human rabies through the use of the existing death reporting system
under local government structures
• close collaboration between the three government departments
involved in the control of rabies
• research on animal rabies and the development of animal and human
rabies vaccines by the University of Veterinary Sciences in Lahore.
• WHO will support all relevant authorities, and in particular the Punjab
Department of Health, in achieving the above interventions over the
next two years.
Pakistan
• Pakistan’s top research institution, Panjwani Center for Molecular
Medicine and Drug Research (PCMD) of ICCBS – University of Karachi
hosted the leading science conference:
• Every year between 2000 to 5000 Pakistanis die of rabies infection
caused by the bite of a rabid animal, usually dogs.
• neglected tropical diseases : Leishmaniasis, scabies, rabies, leprosy,
filariasis, trypsonamiasis, schistosomiasis, dengue, Chagas disease,
Zika, etc.
• Wild animals like bats, raccoons, skunks, and foxes, although any
mammal can get rabies.
Dogs - principle reservoirs in
most of the developing
countries including India and
Pakistan.
About 96% of the mortality
and morbidity associated with
dog bites.
Bats - major source of human
rabies deaths in the
Americas.
Bat rabies - an emerging
public health threat in
Australia and Western
Europe.
Other important reservoirs - Cats,
wolves, jackals, skunks,
raccoons, mongooses and
monkeys.
Man is dead end of the infection -
1) Bite transmission
Human infection by rabies virus usually occurs as a result of a
transdermal bite from an infected wild or domestic animal
more than 95% of human cases are due to bites by infected
dogs
2) Non-bite transmission
Scratches from a rabid animal
Saliva from a rabid animal comes into contact with a victim’s
mucous membranes or fresh skin lesions
3) Rare cases have been reported via:
Inhalation of virus-containing aerosols
Human-to-human transmission through transplantation
Contracting rabies through consumption of milk, raw meat
or animal-derived tissue has never been confirmed in
humans.
Ranges between 2 weeks and 6 years. Average -
between 30-90 days.
length influenced by:
i. site of bite,
ii. depth of bite,
iii. the amount of virus in saliva of the
biting animal, and
iv. the age and immune status of the victim.
INCUBATION PERIOD: Range
from 10 days to 1 year (avg. is 3-
8 weeks)
CLINICAL FEATURES: manifest
in two forms:
1) Furious rabies - the classic
“mad-dog syndrome’’,
restlessness, wandering,
howling, polypnea, drooling,
attacks on other animals,
people or inanimate objects
& swallow foreign objects.
2) Dumb or Paralytic rabies -
manifest by ataxia and
paralysis of the throat and
masseter muscles. Dropping
of the lower jaw is common.
Laryngeal paralysis - ‘hoarse
howling’.
How rabies is
diagnosed
•Rabies can be difficult to diagnose, at least in the early stages. People suspected to be hosts
of the virus usually undergo one of the following tests:
•Direct fluorescent antibody test (DFA) – a tissue sample is taken of the suspected area of
infection and notices if the rabies protein is present; this test is the fastest
•Polymerase chain reaction assay (PCR) – finds the specific DNA of the rabies protein if
present; this is the most accurate
•Animals that do the biting are also tested. They can be diagnosed most easily through
abnormal behavior: an unnaturally increase in drooling, mindless aggression, and nocturnal
animals wandering about during daylight hours all indicate something is very wrong.
Once acquired
virtually 100% fatal
No established
treatment
A palliative approach
may be appropriate for
some patients
Management is focused on
confirming the diagnosis,
preventing transmission to
in-hospital staff and
relatives and supportive
treatment and comfort
and care to the patient
A three-pronged approach -
All carry equal importance
and should be done
simultaneously as per the
category of exposure:
1. Management of animal
bite wound(s)
2. Passive immunization
with Rabies
Immunoglobulin (RIG)
3. Active immunization with
Anti-Rabies Vaccines (ARV)
Categorization of Animal Bites (WHO):.
Cleansing with soap
and water (minimum
10min)
Chemical treatment-
virucidal agents - 70%
alcohol, povidine iodine,
tincture iodine, etc
Local infiltration of
rabies antiserum
Antibiotics
Tetanus toxoid
Wound not to be dressed or
bandaged
Suturing – if inevitable -
done with antiserum
infiltration locally
For Category III bites, combined with vaccine.
provides passive immunity in the form of ready-made
anti-
rabies antibodies.
Two types of RIGs are available:
Equine Rabies Immunoglobulin (ERIG): dose is 40
IU per kg of body weight.
Human Rabies Immunoglobulin (HRIG): dose of 20
IU
per kg of body weight.
RIG should be infiltrated into the depth of the wound
and around the wound as much as anatomically feasible.
Remainder should be injected at an intramuscular
site distant from that of vaccine inoculation.
For all Category II and III exposures irrespective of age
and body weight.
Provides active immunization.
The post-exposure schedule prescribes intra-
muscular doses of vaccine given as 0.5 or 1ml
depending on the vaccine type as four or five
doses over four weeks.
The “ESSEN” regimen administers five
intramuscular doses of rabies vaccine on days
0,3,7,14,28. The four dose regimen prescribes 2 doses
(one on each deltoid/thigh) on day 0 followed by
one dose each on days 7 and 21.
However, recent WHO guideline suggest that in
healthy, fully immunocompetent persons who have
received wound care, RIGs and WHO pre-
qualified rabies vaccine, an alternative PEP
vaccine regimen consisting of four doses
administered IM on days 0, 3, 7 and 14 can be
used as an alternative to the five dose regimen.
In other cases, including WHO category II
exposure, the use of the five-dose Essen regimen
on days 0, 3, 7, 14 and 28 should continue.
Abbreviated multi-site intramuscular regimen
(2-1-1, Zagreb regimen) : In this regimen, one dose
administered in the right and second dose in the
left deltoid on day 0 followed by one dose in the
upper arm on days 7 and 21. This saves two clinic
visits and one dose of vaccine.
The updated Thai Red
Cross Intradermal (ID)
Regimen
(2-2-2-0-2) consists of one dose
of vaccine (0.1ml) given
intradermally at two different
sites usually right and left arm on
days 0,3,7 and 28.
Another is the Oxford or eight
site ID regimen (8-0-4-0-1-1).
One dose of 0.1 ml is
administered intradermally at
eight different sites (upper arms,
lateral thighs, suprascapular
region, lower quadrant of
abdomen) on day 0. Four ID
injections on both upper arms
and lateral thighs on day 7
followed by one injection on
days 28 and 90.
For persons who are at a high risk (veterinarians, those
working in rabies research or diagnostic laboratories,
animal handlers, wildlife officers, people travelling to
high risk areas, children below 15 years ) - one full
dose of vaccine intramuscularly or 0.1ml
intradermally on days 0, 7 and 21 or 28 days.
Serological testing should be done every six months in
above said.
A booster is recommended if the titre falls below 0.5
IU/ml .
In countries where the disease is
endemic, measures include: (OIE)
public awareness and education campaigns (for
the general public, for dog owners and
children);
surveillance and reporting of suspected cases
in susceptible animals;
vaccination programmes for domestic
dogs;
vaccination programmes for wild animals (usually
by distributing oral vaccine baits in the natural
environment);
stray dog population control programmes,
and vaccination programmes where feasible.
research into disease dynamics, suitable vaccines
and vaccine delivery mechanisms for target
populations;
Preventive measures by occupational groups
regularly in contact with animals (such as
The plan –‘Zero
by 30: The
Strategic Plan’ –
centres on a One
Health approach
and addresses
the disease in a
holistic and cross-
sectoral manner
while highlighting
the important
role veterinary,
health and
educational
services play in
rabies prevention
and control.
Vaccine (Manufactured by National Institute of
Health, Islamabad): Purified and inactivated Rabies
virus
• Pre-exposure: Pre-exposure immunization schedule: A total of three
shots given on days 0,7 and 28
• Post-exposure: Days 0, 3, 7, 14, 28 ; Five doses in total.
Adverse reactions & contraindications
• After inoculation, mild local or systemic reactions may occur, which could be
relieved spontaneously. Occasionally rashes may appear. In case of some serious
adverse reactions, such as immediate anaphylactic reactions, angioneurotic
edema or urticaria, symptomatic treatment is recommended.
• Contra indications:
• Because rabies is a fatal disease, there are no contraindications for post-
exposure immunization.
• For pre-exposure immunization, it is not recommended to immunize eligible
individuals with fever, acute disease, serious chronic disease, and with a history
of allergic reaction to antibiotics and/or biological products. It is recommended
to postpone the administration of the vaccine for women in pregnancy or in
lactation, if feasible
