Genetic characteristics of field and attenuated rabies viruses ... - Evira

This method can be used for assessing the efficacy of oral fox vaccination campaigns
and it was demonstrated that by using commercial ready-to-use microplates sensitized
with rabies virus glycoprotein, a simple and rapid ELISA technique enables the obtaining
of a rabies antibody quantization in field fox serum samples (Mebatsion et al., 1989;
Esterhuysen et al., 1995; Cliquet et al., 2000, 2003, 2004, 2007; Servat et al., 2007).
The latex agglutination test is also used to detect rabies-specific antibodies. Latex
beads are sensitized by coating them with purified rabies glycoprotein to detect antiglycoprotein
antibodies in serum samples. The visible agglutination is observed in the
positive sera with a titer ≥ 2 IU/ml within 3–5 min after mixing, while serum samples
containing less than 2 IU/ml do not agglutinate (Madhusudana and Saraswati, 2003).
1.5. Rabies epidemiology
1.5.1. Rabies situation world-wide
Rabies is widely distributed throughout the world and is present in all continents
except Australia, where only bat Lyssavirus has been found, and in Antarctica.
Worldwide, it has been estimated that approximately 55000 persons die annually due to
rabies; 99% of human rabies deaths have occurred in the developing countries. The total
global expenditure on rabies prevention is well over US$ 1 billion annually (Warrel et al.,
1995; WHO Expert Consultation on Rabies, 2005).
Different animal species can be responsible for viral circulation and rabies
transmission in different continents and countries. Canids have been determined to be
the main hosts of the rabies virus in Africa; in most cases they are also responsible for
the transmission of the virus to humans. In addition to canids (domestic and wild dogs,
jackals, and wolves), mongooses, and bats are involved in rabies epidemics, as occurs in
Africa (Adeiga et al., 1996; Bingham, 2005). Dogs are also the primary reservoir for
rabies in Thailand (Tepsumethanon et al., 2005). In the USA, several species are
involved in rabies epidemics but the main reservoirs are raccoons and skunks (Krebs et
al., 2003). An epizootic of raccoon rabies, begun in the USA in the late 1970s, and
developed into one of the largest and most extensive in the history of wildlife rabies
(Childs et al., 2000). Rabies has been detected in rodents and lagomorphs, mostly in
woodchucks (Childs et al., 1997) and also in arctic foxes (Ballard et al., 2001). In
addition, bats are sometimes responsible for the transmission of rabies to humans (Miah,
2005).
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