WHO Standards For Rabies Control

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World Health Organization – Department of Neglected Tropical Diseases – Neglected Zoonotic Diseases team(revised 15 June 2010)

WHO Standards for Rabies Control(prevention of human infection, professional hazards)

F.X.Meslin, T. Hemachuda, H. Wilde and G.Gongal

At the occasion of the OIE Global Conference on Rabies Control : towards sustainable prevention at the source, Incheon (Republic of Korea 7-9 September 2011)

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WHO recommendations on

human rabies vaccine and

immunoglobulin production

and control

- National

Programme for the

control of rabies in

dog

- Control of rabies

in wildlife

- Rabies-free and

provisionally free

countries and areas

- International

transfer of animals

WHO recommendations on all

aspects of human and animal

rabies surveillance prevention

and control and elimination

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Latest WHO

recommendations on

rabies vaccines and

their use for rabies pre

and post-exposure

prophylaxis in WHO

position paper on

rabies vaccines WER,

2010, 85, pp 309-320

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2011

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Professional groups and rabies awareness, risks and prevention

Veterinary and medical practitioners, animal welfare personnel, zoologists and animal conservationists, laboratory staff are some of the groups which must absolutely be aware of the nature of the risk, modes of transmission and prevention of rabies.

Professionals, who are likely to be exposed to the live rabies virus through their work should receive pre-exposure vaccination. This include veterinarians, veterinary technicians working in rabies infected areas, particularly those directly involved in mass vaccination campaigns of dogs and wildlife and laboratory personnel handling suspect samples, animals and live rabies viruses.

Performing unprotected necropsies or autopsies involves a particularly high risk. The use of mask, gloves and a gown as well as glasses when examining and handling a rabies suspected (human or animal) patient and conducting necropsies/autopsies is mandatory. This should protect staff from droplet infection to face and eyes, sites at greatest if not only risk.

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Rabies Pre and Post-exposure Prophylaxis in Humansat www.who.int/rabies

WHO GUIDE

for

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Immediate washing/flushing and disinfection of the wound plus rapid

administration of purified immunoglobulin and vaccine

according to the modalities described in these guidelines assure

prevention of infection in almost all circumstances

General considerations in rabies PEP

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Post-exposure prophylaxis may be discontinued if the animal involved is a dog or cat that remains

healthy for an observation period of 10 days after the exposure occurred; or if the animal is humanely

killed and proven to be negative for rabies by a reliable diagnostic laboratory using a prescribed test.

If the animal at the origin of exposure is suspected of being rabid and is not apprehended, PEP should

be instituted immediately.

initiation of PEP should not await the results of veterinary laboratory diagnosis or be delayed by dog

observation when rabies is suspected,

In areas where canine or wildlife rabies is enzootic, adequate laboratory surveillance is in place, and

data from laboratory and field experience indicate that there is no infection in the species involved,

local health authorities may not recommend anti-rabies prophylaxis.

Discontinuing or deferring PEP: must be an exception in rabies endemic countries

or areas!

Animal-related considerations in PEP

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Category I : -touching, feeding of animals or licks on intact skin

no exposure therefore no prophylaxis if history reliable

Rabies PEP modalities

Category III: -single or multiple transdermal bites or scratches, licks on broken skin, contamination of mucous membrane with saliva (i.e. licks) and suspect contacts with bats:

use immunoglobulin plus vaccine

Category II: -minor scratches or abrasions without bleeding or and nibbling of uncovered skin

use vaccine alone

Definition of categories of contact and use of rabies biologicals:

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Infiltrate into the depth of the wound and around the wound

as much as anatomically feasible of the RIG should be infiltrated around the wound

remainder if any should be injected at an intramuscular site distant from that of vaccine inoculation e.g. into the anterior thigh

Quantities/volume of RIG: 20IU/ kg for Human RIG (HRIG) or 40 IU/ kg of Equine RIG (ERIG)

Rabies PEP modalities

Administration of rabies immunoglobulin (RIG)wounds infiltration with RIG is of upmost importance in category 3 exposure management

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-

as an alternative vaccine dose on day 28 can be omitted in fully immuno-competent patients when immunoglobulin has been also applied on day 0 or within a week after first vaccine dose administration

Vaccines should not be injected into the gluteal region;

Intramuscular regimens for rabies PEP

Two intramuscular schedules for category 2 and 3 exposures:

5 doses im on days 0-3-7-14-28

4 doses im on days 0x2-7-21

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One intradermal PEP regimen for category 2 and 3 exposures

2-site intradermal method ('2-2-2-0-2' )

The volume per intradermal site is 0,1 mL for both PVRV (VerorabTM) and PCECV (Rabipur™)

Intradermal injections reduce

the volume of vaccine required

and vaccine cost by 60% to

80%

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0

10

20

30

40

50

Modernvaccine

im

SMBV

Vaccine costs

PEP in

VIETNAM

Intradermal RV application decreases costs of

human rabies post-exposure prophylaxis

Modern

vaccine

id

45

5

$

ID regimens requiring considerably less vaccine

than IM regimens are particularly appropriate

where vaccine or money is in short supply.

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Pre-exposure rabies vaccination

Groups of persons at high risk of exposure to live rabies virus (laboratory staff, veterinarians, animal handlers and wildlife officers)

Children in highly endemic areas may be considered if vaccine quantities for PEP are adequate

Regimen (with vaccines fulfilling WHO requirements)

three doses of vaccine on days 0, 7 and 28

A dose is either 1 standard intramuscular dose (0.5 or 1 mL) or 0.1mL intradermally

Site of injection: deltoid area of the arm for adults; anterolateral area of the thigh acceptable for children

If antimalarial chemoprophylaxis is applied concurrently, intramuscular injections are preferable to intradermal

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Antibody persists after pre-exposure vaccine

Intramuscular

Ab present No. Subjects

Intradermal

Ab present No. subjects

1 year 38 - 98 % 329 10 - 96 % 352

2 years 100 % 39 66 - 100 % 232

2- 2½ yrs 2½ -5 yrs

-

81 %

-

35

70 %

90 %

128

60

Rapid Fluorescent Focus Inhibition Test

>0.5 IU/ml ( 1:25) titre >1:5

Refs: Dreesen 1983 Bernard 1985 Horman 1987

Morrison 1987 Dreesen 1989 Briggs 1992 Strady 1998

Sabchareon 1998 Jaijaroensup 1999 Briggs 2001

Kamoltham 2007

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Local treatment of wound

no RIG should be applied

Two PEP schedules (with vaccines fulfilling WHO requirements)

one dose on days 0 and 3. The dose is either 1 standard intra muscular dose (which may be 1 ml or 0.5 ml depending on vaccine type ) or one intradermal dose of 0.1 ml per site

or as an alternative a 4-site (one visit only) intradermal PEP consisting of 4 injections of 0.1 mL distributed on each arm and thigh or suprascapular region on days 0.

Decision to use one or the other is left with the health care provider in consultation with the patient.

However full PEP should be given to persons :

who received pre-or post-exposure prophylaxis with vaccines of unproven potency or

in patients in whom immunological memory is not longer assured as a result of HIV/AIDS or other immunosuppressive causes

Rabies PEPof previously vaccinated persons

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Persons working with live rabies virus in diagnostic laboratories, research laboratories, vaccine production laboratories and others professions (veterinarians, animal handlers, wildlife officers...) at permanent risk of exposure to rabies should have:

one serum sample taken every six months

a booster dose when the titre falls below 0.5 IU/ml

Routine booster vaccine doses after primary rabies vaccination are not required for the general public living in

areas of risk.

Booster vaccination and monitoring of previously immunized persons

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Cost of PEP and cost of vaccinating dogs

1 full PEP including RIG + associated patient transport costs and income loss, will cost the average patient around $100 ($93 in Africa and $106 in Asia).

Cost of vaccinating one dog in a mass vaccination campaign is around $2 (with $ 0.30 worth of vaccine)

Cost of 1 full PEP is equivalent to that of vaccinating 50 dogs

On average 2000 PEP are needed per million inhabitants per annum and there are on average 100 000 dogs per million people

But effective dog rabies control with good surveillance leads to reduction in PEP and related costs over time and eventual savings when elimination is reached (5 to 10 years horizon).

Because PEP is required resources used to pay for PEP cannot be transferred to dog rabies control

Other sources of funding need to be found.

Costs of dog vaccination = cost of PEP per million people pa

Documents

WHO Standards For Rabies Control