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The use of FMD vaccines is usually controlled by national or regional FMD control policy.
International standards for FMD vaccines can be found in the European Pharmacopoeia
(Veterinary) (1993), and the OIE Manual of Standards for Diagnostic Tests and Vaccines
(OIE Manual).
Control of endemic FMD relies upon the regular use of inactivated whole virus vaccines,
and prophylactic vaccination may be used alongside importation control and 'emergency'
repeat vaccination as part of an FMD control strategy. As FMDV occurs as seven serotypes,
each of which having the potential for wide antigenic diversity, it has become common
practice to include more than one strain of a given serotype in a multivalent vaccine.
The duration of protective immunity in cattle following vaccination is short-lived in
comparison to that conferred following infection. Therefore it is necessary to vaccinate
annually or bi-annually, and even tri-annually where there is a high risk of exposure to
the virus, for example, in Saudi Arabia. Emergency measures to control an outbreak may
include partial or total 'stamping out' by slaughter and disposal of diseased herds and
flocks, and an emergency 'ring' vaccination campaign around the periphery of the infected
area. The risk associated with partial rather than total 'stamping out' is that carrier
animals may be created and remain alive.
In regions or states recognised as FMD-free, prophylactic vaccination is not allowed, but
a non-vaccination policy has to be supported by certain contingencies and most FMD-free
countries recognise the need for rapid access to sources of vaccine to support emergency
'ring' vaccination measures if an outbreak threatens to become extensive. To this end
several international and national FMD antigen and vaccine banks have been established
over the last 25 years.
In recent years the production and use of FMD vaccines has fallen as more countries
achieve freedom from FMD. However, outbreaks of FMD occur periodically in large areas
of the world including Africa, many Asian countries, much of South America and the Middle
and Far East, despite efforts to control the disease with an annual use of 1.5 billion
doses of vaccine world-wide.
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