Objective—To evaluate postexposure prophylaxis
(PEP) in dogs experimentally infected with rabies.
Procedure—Dogs were sedated and inoculated in
the right masseter muscle with a salivary gland
homogenate from a naturally infected rabid dog (day
0). Six hours later, 5 dogs were treated by administration
of 2 murine anti-rabies glycoprotein monoclonal
antibodies (mAb) and commercial vaccine; 5 received
mAb alone; 5 received purified, heat-treated, equine
rabies immune globulin (PHT-ERIG) and vaccine; 5
received PHT-ERIG alone; 4 received vaccine alone;
and 5 control dogs were not treated. The mAb or PHTERIG
was administered at the site of rabies virus inoculation.
Additional vaccine doses for groups mAb plus
vaccine, PHT-ERIG plus vaccine, and vaccine alone
were administered IM in the right hind limb on days
3, 7, 14, and 35.
Results—All control dogs and dogs that received only
vaccine developed rabies. In the PHT-ERIG and vaccine
group, 2 of 5 dogs were protected, whereas
none were protected with PHT-ERIG alone. Use of
mAb alone resulted in protection in 4 of 5 dogs.
Administration of mAb in combination with vaccine
provided protection in all 5 dogs.
Conclusions and Clinical Relevance—Current
national guidelines recommend euthanasia or a 6-
month quarantine for unvaccinated animals exposed
to rabies. Findings from this study document that vaccine
alone following severe exposure was unable to
provide protection from rabies. However, vaccine
combined with mAb resulted in protection in all treated
dogs, revealing the potential use of mAb in PEP
against rabies in naïve dogs. (Am J Vet Res