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
Summary—During 2006, 49 states and Puerto Rico reported 6,940 cases of rabies in animals and 3 cases in humans to the CDC, representing an 8.2% increase from the 6,417 cases in animals and 1 case in a human reported in 2005. Approximately 92% of the cases were in wildlife, and 8% were in domestic animals. Relative contributions by the major animal groups were as follows: 2,615 raccoons (37.7%), 1,692 bats (24.4%), 1,494 skunks (21.5%), 427 foxes (6.2%), 318 cats (4.6%), 82 cattle (1.2%), and 79 dogs (1.1%). Compared with numbers of reported cases in 2005, cases in 2006 increased among all groups except cattle. Increases in numbers of rabid raccoons during 2006 were reported by 11 of the 20 eastern states where raccoon rabies was enzootic, and reported cases increased by 3.2% overall, compared with 2005.
On a national level, the number of rabies cases in skunks during 2006 increased by 6.1% from the number reported in 2005. Once again, Texas reported the greatest number (n = 351) of rabid skunks and the greatest overall state total of animal rabies cases (889). No cases of rabies associated with the dog/coyote rabies virus variant were reported. The last identified case of this canine rabies virus variant was identified in March 2004, along the US/Mexi-co border. With 2006 marking the second year of no apparent transmission of the dog/coyote variant, these findings from surveillance data support the contention that the canine rabies virus variant is no longer in circulation in the United States. Total number of cases of rabies reported nationally in foxes increased 13.6%, compared with 2005. Increases in the number of reported rabid foxes were attributable to greater numbers of foxes reported with the Arctic fox rabies virus variant in Alaska, the Texas gray fox rabies virus variant in Texas, and the raccoon rabies virus variant in Virginia. The 1,692 cases of rabies reported in bats represented a 14.5% increase, compared with numbers reported in 2005, making bats the second most reported rabid animal behind raccoons. Cases of rabies in cats, dogs, horses and mules, and sheep and goats increased 18.2%, 3.9%, 12.8%, and 22.2%, respectively, whereas cases reported in cattle decreased 11.8%. In Puerto Rico, reported cases of rabies in mongooses increased 9.2%, and rabies in domestic animals, presumably attributable to spillover infection from mongooses, increased 20%.
Three cases of human rabies were reported from Texas, Indiana, and California during 2006. The cases in Indiana and Texas were attributed to bat rabies virus variants, whereas the case in California was attributed to an exposure to a dog in the Philippines.
Objective—To identify cases of rabies involving vaccinated dogs and cats in the United States.
Design—Retrospective data review.
Sample Population—41 states that reported ≥ 1 rabid dog or cat between 1997 and 2001.
Procedures—States were contacted to request information on numbers of dogs and cats tested for rabies between 1997 and 2001. For animals with a history of rabies vaccination, respondents were asked to provide details of the vaccination history, age, history of exposure to rabid animals, time between exposure and onset of clinical signs, clinical signs, duration of clinical signs, and whether the animal had died or was euthanatized.
Results—21 of the 41 (51%) states agreed to participate in the study. A total of 264 rabid dogs and 840 rabid cats were identified during the study period. Thirteen (4.9%) rabid dogs and 22 (2.6%) rabid cats had a history of rabies vaccination. Of these, 2 dogs and 3 cats were classified as currently vaccinated. Overall, 6 animals (1 dog and 5 cats) had a history of receiving 2 doses of rabies vaccine in their lifetime, including 2 cats that were classified as currently vaccinated.
Conclusions and Clinical Relevance—Results suggested that rabies is uncommon in vaccinated dogs and cats but can occur. Veterinarians should include rabies in the differential diagnosis for any dog or cat with clinical signs compatible with rabies regardless of vaccination history. Continued surveillance is imperative to document vaccination failure and identify trends related to vaccination failure.
Summary—During 2005, 49 states and Puerto Rico reported 6,417 cases of rabies in nonhuman animals and 1 case in a human being to the CDC, representing a 6.2% decrease from the 6,836 cases in nonhuman animals and 8 cases in human beings reported in 2004. Approximately 92% of the cases were in wildlife, and 8% were in domestic animals. Relative contributions by the major animal groups were as follows: 2,534 raccoons (39.5%), 1,478 skunks (23%), 1,408 bats (21.9%), 376 foxes (5.9%), 269 cats (4.2%), 93 cattle (1.5%), and 76 dogs (1.2%). Compared with numbers of reported cases in 2004, cases in 2005 decreased among all groups, except bats, horses, and other wild animals. Decreases in numbers of rabid raccoons during 2005 were reported by 10 of the 20 eastern states in which raccoon rabies was enzootic and decreased overall by 1.2%, compared with 2004.
On a national level, the number of rabies cases in skunks during 2005 decreased 20.4% from the number reported in 2004. Once again, Texas reported the greatest number (n = 392) of rabid skunks and the greatest overall state total of rabies cases (741). Texas reported no cases of rabies associated with the dog/coyote rabies virus variant and only 8 cases associated with the Texas gray fox rabies virus variant (compared with 22 cases in 2004). The total number of cases of rabies reported nationally in foxes decreased 3.3%, compared with those reported in 2004. The 1,408 cases of rabies reported in bats represented a 3.5% increase over numbers reported in 2005. Cases of rabies in cats, dogs, cattle, and sheep and goats decreased 4.3%, 19.2%, 19.1%, and 10%, respectively, whereas cases reported in horses and mules increased 9.3%. In Puerto Rico, reported cases of rabies in mongooses increased 29.8%, and rabies in domestic animals decreased 37.5%.
One case of human rabies was reported from Mississippi during 2005. This case was submitted by the state to the CDC's unexplained deaths project and diagnosed as rabies retrospectively.
Objective—To compare anamnestic antibody responses of dogs and cats with current versus out-of-date vaccination status.
Animals—74 dogs and 33 cats.
Procedures—Serum samples were obtained from dogs and cats that had been exposed to rabies and brought to a veterinarian for proactive serologic monitoring or that had been brought to a veterinarian for booster rabies vaccination. Blood samples were collected on the day of initial evaluation (day 0) and then again 5 to 15 days later. On day 0, a rabies vaccine was administered according to label recommendations. Paired serum samples were analyzed for antirabies antibodies by means of a rapid fluorescent focus inhibition test.
Results—All animals had an antirabies antibody titer ≥ 0.5 IU/mL 5 to 15 days after booster vaccination. Dogs with an out-of-date vaccination status had a higher median increase in titer, higher median fold increase in titer, and higher median titer following booster vaccination, compared with dogs with current vaccination status. Most (26/33) cats, regardless of rabies vaccination status, had a titer ≥ 12 IU/mL 5 to 15 days after booster vaccination.
Conclusions and Clinical Relevance—Results indicated that dogs with out-of-date vaccination status were not inferior in their antibody response following booster rabies vaccination, compared with dogs with current vaccination status. Findings supported immediate booster vaccination followed by observation for 45 days of dogs and cats with an out-of-date vaccination status that are exposed to rabies, as is the current practice for dogs and cats with current vaccination status.
Summary—During 2013, 53 reporting jurisdictions reported 5,865 rabid animals and 3 human rabies cases to the CDC, representing a 4.8% decrease from the 6,162 rabid animals and 1 human case reported in 2012. Ninety-two percent of reported rabid animals were wildlife. Relative contributions by the major animal groups were as follows: 1,898 raccoons (32.4%), 1,598 bats (27.2%), 1,447 skunks (24.7%), 344 foxes (5.9%), 247 cats (4.2%), 86 cattle (1.5%), and 89 dogs (1.5%). One human case was reported from Maryland. The infection was determined to have been transmitted via organ transplantation. Infection in the organ donor, a North Carolina resident, was retrospectively diagnosed. Both the organ donor and the organ recipient were infected with the raccoon rabies virus variant. The third human case, reported by Texas, involved a Guatemalan resident who was detained while crossing the US border. The infection was determined to be caused by a canine rabies virus variant that circulates in Central America.
OBJECTIVE To assess the immunogenicity of thermostable live-attenuated rabies virus (RABV) preserved by vaporization (PBV) and delivered to the duodenal mucosa of a wildlife species targeted for an oral vaccination program.
ANIMALS 8 gray foxes (Urocyon cinereoargenteus).
PROCEDURES Endoscopy was used to place RABV PBV (n = 3 foxes), alginate-encapsulated RABV PBV (3 foxes), or nonpreserved RABV (2 foxes) vaccine into the duodenum of foxes. Blood samples were collected weekly to monitor the immune response. Saliva samples were collected weekly and tested for virus shedding by use of a conventional reverse-transcriptase PCR assay. Foxes were euthanized 28 days after vaccine administration, and relevant tissues were collected and tested for presence of RABV.
RESULTS 2 of 3 foxes that received RABV PBV and 1 of 2 foxes that received nonpreserved RABV seroconverted by day 28. None of the 3 foxes receiving alginate-encapsulated RABV PBV seroconverted. No RABV RNA was detected in saliva at any of the time points, and RABV antigen or RNA was not detected in any of the tissues obtained on day 28. None of the foxes displayed any clinical signs of rabies.
CONCLUSIONS AND CLINICAL RELEVANCE Results for this study indicated that a live-attenuated RABV vaccine delivered to the duodenal mucosa can induce an immune response in gray foxes. A safe, potent, thermostable RABV vaccine that could be delivered orally to wildlife or domestic animals would enhance current rabies control and prevention efforts.