Rabies Guide 2010.pdf - the South African Veterinary Council

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Fraudulent vaccines, nerve-tissue derived vaccines
and equine immunoglobulin commonly associated
with severe adverse reactions may be used in these
countries. 89 In certain areas tourists are frequently
exposed to dogs, for example a survey of European
travellers in Thailand found that in less than a three
week period 1,3% of tourists experienced dog bites
and 8,9% dog licks. 90 Advantages of pre-exposure
rabies vaccination include requiring only two boosters,
on days 0 and 3, if there is an exposure, no need for
immunoglobulin, and diminished concern about
inadequate therapy and vaccine failure.
Advice and vaccination should be adapted to the
individual needs and exposure risks of travellers,
taking into account the area visited, local rabies
epidemiology, mode of travel, and underlying
medical conditions and medication. Travellers who
are immunocompromised by disease or selected
medications are a group deserving particular attention
as immune response to vaccine may be suboptimal.
They should avoid activities for which rabies preexposure
vaccination is indicated. When this is not
possible, immunocompromised individuals who are
at risk of rabies exposure should be vaccinated and
their antibody titres checked post-vaccination. 91
Management of humans exposed
to rabies
The death of a person from rabies should be viewed as
a health system failure. This contention is supported
by a review of failed post-exposure prophylaxis in
Thailand, which found that delays, failure to provide
post-exposure prophylaxis or deviations from the
recommended regimen contributed directly to the
deaths of young children. 92
Findings from studies in South Africa and Thailand have
highlighted deficiencies in health workers’ knowledge
on managing suspected rabies exposures. 49,93
It is therefore recommended that a confidential
enquiry routinely be conducted to establish avoidable
factors which may have contributed to the death.
Although no controlled human trial of rabies postexposure
prophylaxis utilising wound treatment,
immunoglobulin and vaccination has been conducted
and such a study would be unethical, extensive
global experience provides convincing support for this
approach. 94,95,96
There is a critical need for veterinary and health
workers to be adequately trained on assessing rabies
risk and appropriate response. It is also imperative
that health and veterinary workers involved in
managing human cases with potential exposure to
rabies virus remain in close communication so that
patient management can be modified by data about
the source animal. The health worker is obliged to
make contact with the responsible state veterinarian.
Laboratory-confirmed human rabies and exposure to
proven rabid animals is notifiable in South Africa.
Assessing risk after exposure
Important factors that assist decisions on prophylaxis,
include details of the nature of the contact and the
implicated animal’s behaviour. 97 It is imperative that
prophylaxis be instituted as soon as possible after
exposure to rabies virus, even before there is laboratory
confirmation of rabies in the animal. 98 Ideally postexposure
prophylaxis should be administered to
all bite victims, but availability and costs of the
biologicals is a problem. The approach adopted in
South Africa focuses on providing prophylaxis to
those individuals at high risk of rabies infection.
To reduce the risk of rabies,
it is important that thorough
cleaning of the bite wound is
initiated as soon as possible
Judgement on whether to initiate post-exposure
prophylaxis is assisted by an estimation of risk based
on the following criteria, with a high risk of exposure
necessitating vaccination: 41
• type of contact. Bats may be involved in transmitting
rabies-related viruses, i.e. Duvenhage and Lagos Bat
viruses, and any encounters should be considered.
Small rodents eg. mice and rats commonly found
in and around dwellings are not typically associated
with rabies. To date in South Africa there has only
been one transmission of rabies associated with a
bite from a baboon. (Fig. 7, pg 41 or Appendix 2)
• incidence of rabies in the animal’s district of
origin
• animal’s behaviour (any abnormal behaviour could
indicate rabies)
• species of animal involved (Table 2, page 10)
• vaccination status of animal (if not vaccinated, then
higher risk)*