Page 608 - The Veterinary Laboratory and Field Manual 3rd Edition

Glossary 545

collective vision for the benefit of a community. having a specific disease that subsequently die
This is an approach that is now favoured by inter- as a result of that disease. This term is usually
national development agencies to ensure that applied in an outbreak of an acute disease in
appropriate solutions are identified and imple- which all cases are monitored for an adequate
mented to resolve community human, animal and period of time to include all attributable deaths.
environmental health problems. The fatality rate is not the same as the mortal-
ity rate.
Disease – A term used for any condition (internal
or external) that impairs the normal functioning FAO – Food and Agriculture Organization of the
of an organism or body. The cause may be infec- United Nations – see http://www.fao.org/.
tious (that is, where a pathogen is transmitted
from one individual to another) or non-infectious Incidence – The number of new cases of a
(that is, vector borne diseases, metabolic dis- disease occurring in a specified period. The inci-
eases, toxins and so on). dence rate is the number of new cases of the
disease reported in a specific time (for example,
ELISA – Enzyme-linked immunosorbent assay per year or month) divided by the number of
is now a well-accepted and popular immuno- animals in the population at risk.
assay format. Many ELISA type assays are now
available in kit form and/or pen side tests so this Morbidity rate – The proportion of animals in
technology is much more readily attainable for a given population that develop clinical disease.
both the regional veterinary laboratory and field Disease specific morbidity rate is the proportion
staff. of animals which develop clinical signs attrib-
utable to the disease under investigation and
Endemic – The constant presence of a disease or confirmed by diagnostic tests.
infectious agent within a given geographic area. It
may refer to the usual prevalence of a given disease Mortality rate – The proportion of animals in
within an area or a relatively new but constant a given population that die during a disease
situation. The term enzootic can also be used. outbreak. Disease specific mortality rate is the
proportion of animals which die following a
Epidemic – The occurrence in a country or specific disease (that is, confirmed by diagnostic
region of cases of an illness (or disease outbreak) tests).
clearly in excess of the expected level. The num-
ber of cases occurring in an epidemic will vary OIE – The Office International des Epizooties,
according to the cause, that is, the infectious OIE, was created in 1924 in an effort to address
agent involved and its method of transmission, emerging animal health issues at the global
the size and type of population exposed, previ- level. In 2003, the Office became the World
ous exposure to the disease agent and the time Organisation for Animal Health but kept its
and place of occurrence. The term ‘epizootic’ can historical acronym, OIE. The OIE is the intergov-
also be used. ernmental organisation responsible for improving
animal health worldwide and is recognised as a
Emerging disease – A disease that has appeared standard setting organisation by the World Trade
in a population for the first time, or that may Organization (WTO). In 2019, the OIE had a
have existed previously but is rapidly increasing total of 182 Members and maintains permanent
in incidence or geographic range.
relations with 71 other international and regional
Fatality rate – Usually expressed as a percent- organisations and has Regional and sub-regional
age and is the number of animals diagnosed as Offices on every continent (http://www.oie.int/).

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