Diseases / List of Viral Diseases / Rabies (Viral Disease) / Detailed Disease Description:
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Editorial Overview of Disease Characteristics for specified SPECIES/TAXA for Rabies: Use sub-contents list below, or simply scroll down the page to view findings. See also: Rabies - Detailed Clinical Signs (Disease Reports) Limited data on rabies in general is provided in the literature reports but is not intended to be comprehensive.

Overview of Clinical Signs

SPECIES

OVERVIEW

Mammals general Mammalia - Mammals (Class)
 
General summary:
  • "Most of the clinical signs of rabies are expressions of impaired neuronal function (altered neurotransmission) in the CNS. the mechanisms involved are largely unknown." (J214.187.w1)
Body temperature:
Neurological signs:
Prodromal stage:
  • Not usually seen in wild animals. Recognised in humans and may be seen in closely observed pets. (B47)
  • Vague changes in temperament. Often not noticed. (B47)
  • Restlessness may be noted. (B209.1.w1)
  • Increased nervousness or loss of normal fear responses, hyperactivity, hypersensitivity to light/noise and tremor may be seen. (J15.23.w4)
  • Paresthesia at the site of inoculation; this may result in self-inflicted wounds. (B209.1.w1)
  • Biting or rubbing at the initial infection site. (J15.23.w4)
Furious form: 
  • Excitation, 
  • Generalised excitative signs:
    • Hyperaesthesia to stimuli (auditory, visual and tactile). (B209.1.w1)
    • Sudden and apparently unprovoked (or as a response to mild provocation) agitation and aggression to either other individuals (may attempt to bite anything or anyone that approaches) or inanimate objects. (B47, B209.1.w1, J15.23.w4)
    • "Fly snapping" without a visible target. (J15.23.w4)
    • Wild animals may lose their normal wariness around humans and domestic animals, show altered activity cycles, and either become solitary or become more gregarious than normal. (B209.1.w1)
    • Excessive wandering beyond the animal's normal home range. (J15.23.w4)
    • Often but not always drooling of saliva due to partial paralysis of the tongue and lower jaw. (J15.23.w4)
    • Abnormal vocalisation. (J15.23.w4)
    • Further CNS excitation may lead to hyperactivity, disorientation, confusion, photophobia, pica, incoordination, convulsive seizures. (B47, B209.1.w1)
  • Other nervous signs: head tilt, head pressing or butting, altered phonation (voice) and "star-gazing" may be noted. (B209.1.w1)
  • Cranial nerve signs: facial asymmetry, trismus, choking, tongue lolling, drooling, drooping lower jaw, prolapse of the third eyelid and anisocoria may be noted. (B209.1.w1)
  • Autonomic excitation: labile hypertension, hyperventilation, muscle tremors, priapism, altered libido, hypo- or hyperthermia may occur. (B209.1.w1)
Paralytic form: 
  • Paresis or paralysis. Usually follows the furious form but sometimes this is the only manifestation. Usually lasts only one to two days. Terminal form of rabies. Ends with death of the animal. (B47)
    • Extensive paralysis, usually initially affecting the hindquarters, later generalised limb weakness, jaw paralysis resulting in dysphagia, paralysis of the eyelids, paralysis of respiratory muscles causing respiratory distress. Profuse salivation but an inability to chew (hydrophobia is seen only in humans). Convulsions, coma and death. (J15.23.w4)
    • Progressive prostration, lethargy, paresis; frequent urination or incontinence, tenesmus, constipation, flaccidity of the tail and decreased spinal reflexes may be evident, also ataxia causing knuckling or swaying and flaccid paralysis which is ascending and may be symmetrical or asymmetrical, eventually progressing to respiratory and cardiac failure. Hypothalamic and hypophysial dysfunction may occur, leading to acute organ wasting such as cardiomyopathy. Finally coma, multiorgan failure and death. (B209.1.w1)
    • This form be seen directly following the prodromal stage but more usually is seen after the furious stage. (B209.1.w1)
Sequelae:
  • Rare survivors of clinical rabies may have severe neurological sequelae. (B336.76.w76)
Digestive signs:
  • During the prodrome, nonspecific signs, generally only lasting one or two days, may include inappetance, dysphagia, vomiting and diarrhoea. (B209.1.w1)
  • In animals with the furious form, often but not always drooling of saliva due to partial paralysis of the tongue and lower jaw. (J15.23.w4)
  • In animals with the paralytic form, profuse salivation but an inability to chew (hydrophobia is seen only in humans). (J15.23.w4)
  • Pica may develop during the furious stage. (B209.1.w1)
  • In individuals with the paralytic form, constipation may occur. (B209.1.w1)
Urinary signs:
  • In individuals with paralytic rabies, frequent urination or incontinence may be noted. (B209.1.w1)
Respiratory signs:
Ophthalmic signs:
  • Prolapse of the third eyelid and anisocoria may be noted. (B209.1.w1)
  • "Staring" eyes. (J15.23.w4)
  • Photophobia may develop during the furious stage. (B209.1.w1)
Ear, nose and throat signs:
  • Abnormal vocalisation may be noted. (J15.23.w4)
Dermatological signs:
  • Paresthesia may occur at the site of inoculation; this may result in self-inflicted wounds. (B209.1.w1)
  • Biting or rubbing at the initial infection site may be noted. (J15.23.w4)
Recovery and Convalescence:
  • Rare survivors of clinical rabies may have severe neurological sequelae. (B336.76.w76)

LITERATURE REPORTS: 
Prodromal stage:
  • Not usually seen in wild animals. Recognised in humans and may be seen in closely observed pets. (B47)
  • Vague changes in temperament. Often not noticed. (B47)
  • Nonspecific signs: generally only lasting one or two days. May include restlessness. (B209.1.w1)
  • Increased nervousness or loss of normal fear responses, hyperactivity, hypersensitivity to light/noise, tremor and dyspnoea. (J15.23.w4)
  • Local signs:
    • Paresthesia at the site of inoculation; this may result in self-inflicted wounds. (B209.1.w1)
    • Biting or rubbing at the initial infection site. (J15.23.w4)
Furious form: 
  • Excitation, affected individual snaps at imaginary objects and may attempt to bite anything or anyone that approaches. Convulsive seizures during this stage may be fatal. Generally animals progress from this stage to the paralytic form before death. (B47)
  • Generalised excitative signs: hyperaesthesia to stimuli (auditory, visual and tactile), sudden and apparently unprovoked agitation and aggression to either other individuals or inanimate objects. Wild animals may lose their normal wariness around humans and domestic animals, show altered activity cycles, and either become solitary or become more gregarious than normal. Further CNS excitation may lead to hyperactivity, disorientation, confusion, photophobia, pica, incoordination, convulsive seizures. (B209.1.w1)
  • Biting in response to mild provocation, "fly snapping" without a visible target, "staring" eyes, often but not always drooling of saliva due to partial paralysis of the tongue and lower jaw. Abnormal vocalisation, excessive wandering beyond the animals normal home range. (J15.23.w4)
  • Other nervous signs: head tilt, head pressing or butting, altered phonation (voice) and "star-gazing" may be noted. (B209.1.w1)
  • Cranial nerve signs: facial asymmetry, trismus, choking, tongue lolling, drooling, drooping lower jaw, prolapse of the third eyelid and anisocoria may be noted. (B209.1.w1)
  • Autonomic excitation: labile hypertension, hyperventilation, muscle tremors, priapism, altered libido, hypo- or hyperthermia may occur. (B209.1.w1)
Paralytic form: 
  • Paresis or paralysis. Usually follows the furious form but sometimes this is the only manifestation. Usually lasts only one to two days. Terminal form of rabies. Ends with death of the animal. (B47)
  • May be seen directly following the prodromal stage but more usually is seen after the furious stage. (B209.1.w1)
  • Progressive prostration, lethargy, paresis; frequent urination or incontinence, tenesmus, constipation, flaccidity of the tail and decreased spinal reflexes may be evident, also ataxia causing knuckling or swaying and flaccid paralysis which is ascending and may be symmetrical or asymmetrical, eventually progressing to respiratory and cardiac failure. Hypothalamic and hypophysial dysfunction may occur, leading to acute organ wasting such as cardiomyopathy. Finally coma, multiorgan failure and death. (B209.1.w1)
  • Extensive paralysis, usually initially affecting the hindquarters, later generalised limb weakness, jaw paralysis resulting in dysphagia, paralysis of the eyelids, paralysis of respiratory muscles causing respiratory distress. Profuse salivation but an inability to chew (hydrophobia is seen only in humans). Convulsions, coma and death. (J15.23.w4)
Sequelae:
  • Rare survivors of clinical rabies may have severe neurological sequelae. (B336.76.w76)

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Common Raccoon Procyon lotor - Common Raccoon
 
General summary:
  • Raccoons with rabies often show altered behaviour, such as appearing around human dwellings during daylight or wandering aimlessly, and may appear obviously sick, incoordinated or paralysed. Raccoons with rabies are often reported to be unaggressive but to lose their fear of humans and dogs. Frankly aggressive behaviour is also reported, but some animals are specifically noted not to be aggressive, and even to be excessively friendly. "Sick" animals may bite when handled. 
  • Some trapped raccoons confirmed rabid have shown no behavioural signs of rabies. 
  • May be found dead. (J1.37.w2, P66.1.w1)
  • May appear sick (unspecified). (B358.4.w4, B360.16.w16)
  • May be injured. (J101.126.w1)
  • Prodromal signs of reduction or cessation of eating and drinking have been seen in experimental infection. (J2.37.w1)
Neurological signs:
  • Found disorientated or wandering, aimlessly or obviously sick. (J1.37.w2, J1.42.w3, J330.75.w1, P103.1983.w1)
  • Showing non-specified abnormal/strange behaviour. (P66.1.w1, J1.21.w6)
    • Found within mammalian exhibits at a zoo. (P103.1983.w1)
  • Active during the day. (B358.4.w4, J1.21.w6, J101.126.w1, P66.1.w1)
  • Excessive tameness or friendly behaviour. (J101.126.w1, J330.75.w1, P66.1.w1)
  • Non-aggressive behaviour. (J1.6.w3)
  • Lack of interest in other animals. (J196.58.w1)
  • Failure to avoid dogs. (J101.126.w1)
  • Following humans. (J196.58.w1)
  • Lack of fear of humans. (B358.4.w4)
  • Aggressive behaviour, including unprovoked or provoked attacks on humans or other animals. (B358.4.w4, B360.16.w16, J1.6.w3, J1.21.w6, J1.38.w1, J1.42.w3, J4.157.w2, J101.126.w1, J196.58.w1, P66.1.w1)
  • Incoordination, staggering, ataxic, wobbly or with an irregular gait. (B358.4.w4, B360.16.w16, J1.42.w3, J101.126.w1, P66.1.w1, P103.1983.w1)
  • Paralysed or unable to walk. (B358.4.w4, B360.16.w16, J101.126.w1, P66.1.w1)
  • Lethargy. (J212.4.w1)
  • Circling. J212.8.w1)
  • Head-pressing. J212.8.w1)
  • Head-tilt, excess licking, mainly of the genital area and tail tip. (J212.8.w1)
  • Self-mutilation of the limbs or genital area (in raccoons developing signs overnight while not observed). (J212.8.w1)
  • Increased distance of movement. (J1.34.w8)
Miscellaneous signs:
  • A skunky odour was noted in about 25% of raccoons in one outbreak. (J1.21.w6)
  • Impaled with porcupine quills (J1.42.w3, J14.48.w1, J435.119.w2): 12.8% were noted to be impaled with porcupine quills in one study (J1.42.w3); there was a highly significant (chi square = 75.97, P<0.0001) relationship between the presence of quills and the diagnosis of rabies, for 1079 raccoons in Canada submitted for testing. Quills are rarely present in normal raccoons. (J14.48.w1)
Digestive signs:
  • Failure to eat food provided was one of the first signs in a raccoon injected intramuscularly in the right hind leg with 0.2 ml of a skunk rabies isolate. (J196.58.w1)
  • One raccoon being hand-reared started refusing to eat. (J4.163.w4)
  • Mucoid diarrhoea was reported in one raccoon. (J212.4.w1)
Respiratory signs:
  • Laboured breathing, coughing and retching was noted in the last two days before death of a hand-reared raccoon (neurological signs lasted ten days). (J4.157.w2)
  • Abnormal vocalisations. (J1.42.w3, J435.119.w2)
Recovery and Convalescence:
  • There is one report of a raccoon challenged with street rabies (105.5 MICLD50 strain MD5951) six months after oral vaccination with vaccinia-rabies glycoprotein recombinant (V-RG) vaccine, which developed clinical neurological signs of rabies then recovered, but with a residual head tilt present ninety days later. (J270.10S4.w2)

LITERATURE REPORTS: 
Natural infections
  • In a study of 38 incidents involving rabid raccoons in Florida between 1951 and 1958, none of the raccoons had attacked either people or dogs "unless a close approach was followed by an overt act by the victim [human or dog]". Rabid raccoons were found wandering "often obviously sick and in daylight, into doorways or along streams and highways." Some rabid raccoons appeared so tame they were thought to be escaped pet animals. (J330.75.w1)
  • Rabies was diagnosed in a hand-reared raccoon in California in 1969. The animal had been obtained by a hunter in June at two weeks old and died 10th November. Aggressive behaviour was observed from ten days before death and in the last two day the animal showed laboured breathing, coughing and retching. At necropsy there was copious frothy discharge from the mouth, frothy fluid filling the trachea and bronchi, and congestion of the trachea, bronchi, lungs, brain and meninges. Rabies was confirmed by fluorescent antibody test (brain and salivary tissues were tested). The raccoon had had limited freedom during the two months before its death; no contact with wild species had been observed but a skunk had "wandered peculiarly" over the property one day and a dead skunk had been found the following day. (J4.157.w2)
  • In one incident in Kansas, five raccoon kittens had been found on a farm; three died within two weeks but were not examined. One of the two remaining kittens was exhibited in a class at a local school and many children handled it. Soon after, it refused to eat and the family caring for it attempted to force-feed it, dipping their fingers in milk then placing the fingers in the raccoon's mouth. The raccoon died, was examined and was rabies positive by the fluorescent antibody test (the fifth kitten was rabies negative). Nobody had been specifically bitten, but about 250 people had handled the animal, and 51 of those were given PEP. (J4.163.w4)
  • Raccoons with rabies are typically non-aggressive. Furious behaviour is reported in rabid raccoons much less commonly than in rabid foxes. (J1.6.w3) 
    • During an epizootic of raccoon rabies on Long Boat Key, Florida, the behaviour of affected raccoons varied "from frankly aggressive to sick and paralysed"; aggressive behaviour noted included attacks on humans and fights with dogs. (J1.6.w3)
  • Some individuals trapped and found to be rabid showed no behavioural signs of rabies. (J1.6.w3)
  • Aggressive behaviour was seen in 15 of 45 rabid raccoons reported during one outbreak on an island in Florida, with individuals variously attacking humans (seven), fighting with dogs (six) and fighting other raccoons (two). A further 13 raccoons were obviously sick or incoordinated, four were unable to walk, 11 were found within yards during daylight hours and two were hit by cars. One of the sick animals bit a person trying to remove it from a garage. (B358.4.w4)
  • A correlation has been noted between some forms of aberrant behaviour and laboratory-confirmed rabies in raccoons, with 64% of raccoons which were recorded as attacking domestic dogs in inhabited areas being rabid as well as 56% of raccoons found as road kills, 56% of those seen staggering or with an irregular gait, and 54% of raccoons found around human residences. (B358.4.w4)
  • Of 570 raccoons in Georgia reported positive for rabies between 1963 and 1970, 39% were found within yards during daylight hours, 34% were attacking or fighting with dogs, 13% either showed no fear of, or were attacking, humans, 7% were seen walking with an irregular gait and 6% were killed on, or found dead on, the road. It was noted that 47% showed some type of aggressive behaviour and that there were many severe, unprovoked attacks by rabid raccoons on humans. (B358.4.w4)
  • Of two caged raccoons with naturally acquired rabies, one showed aggressive behaviour for three days, then became paralysed and prostrate, and died on the eighth day. The other individual, which had a longer incubation period, showed irregular movements, paralysis and death, with clinical signs lasting only three days. (B358.4.w4)
  • An individual in North Dakota in 1958 appeared round farm buildings and would not leave. It ignored livestock, including fowl, followed humans in the farmyard and was quiet and unaggressive when approached, although it did fight with a dog when provoked by the dog to do so. (J196.58.w1)
  • A wild-born raccoon which had been reared as a pet from two weeks old suddenly displayed aggressive behaviour to its owners at five months old and died from rabies ten days later (B358.4.w4, J4.157.w2)
  • Of the first three raccoon rabies cases reported in Ontario, Canada, the first animal was found dead in a dog kennel (with three dogs), the second attacked a dog on a residential property while the third was found "wandering aimlessly" in a small residential community. (J1.37.w2)
  • In a study, 82% of raccoons to which domestic animals had been exposed were rabies positive and many raccoons found dead and submitted for rabies testing (of which 67% were rabies positive) were found with dogs. (J101.126.w1)
  • During an outbreak in Virginia, in Loudoun County, 78% of infected raccoons were out during the day (versus 40% rabies negative raccoons, 44% (versus 33%) were observed near a human dwelling, 37% (versus 10%) had contact with dogs, 28% (versus 15%) acted "drunk", 26% (versus 7%) acted "strange", 20% (versus 29%) were out during the night, 11% (versus 7%) were aggressive, 6% (versus 38%) appeared normal, 3% versus 19% had contact with humans and 25% (versus 6%) had a skunky odour. The skunky odour appears to be related to raccoon anal gland secretions and reduced hygiene of infected raccoons; there may be loss of voluntary control to the anal glands with unintentional fouling of the raccoon, also hyperexcitability causes hyperstimulation of the glands and therefore excessive secretions. (J1.21.w6)
  • Note: Raccoons have been confirmed laboratory positive for rabies without showing any behavioural signs of rabies. (J1.6.w3)
  • Of two rabid raccoons from Pennsylvania, one was described as "seen exhibiting neurologic signs during daylight hours" while the other "appeared lethargic, had mucoid diarrhoea and died on the second day of captivity" (having been trapped alive). (J212.4.w1)
  • Data from about 700 raccoons from six counties and cities in four states affected early in the mid-Atlantic raccoon rabies outbreak found that: 
    • Submitted raccoons were most often (73%) sighted during the day, with just 5% sighted around dawn, 6% around dusk and 16% at night. Of those sighted during the day, 96% were rabid, compared to 71% of those found at dawn, 92% of those found at dusk and 89% of those found at night. (P66.1.w1)
    • 55% (272 of 449) raccoons were dead when collected, 33% were behaving abnormally and only 12% were considered to show normal behaviour. 93% of those collected when already dead, and 85.5% of those behaving abnormally were rabid as well as 45% of those behaving normally. (P66.1.w1)
    • Of abnormal behaviours reported, aggression or wobbly gait were seen most commonly while others were overly friendly, paralysed or injured. 93.8% of aggressive animals, 94.7% of overly friendly, 98.5% of wobbly, 94.4% of paralysed and 76.7% of injured raccoons were rabies positive. (P66.1.w1)
    • Road kill animals accounted for 5% of submitted raccoons, 20% were found dead and 11% were trapped, while 63% were collected in other circumstances (killed by individuals or their dogs, or captured and killed by animal wardens). 60% of road killed raccoons, 90.9% of raccoons found dead and 91.6% of "other" raccoons were rabid, but only 28.8% of trapped raccoons were positive. (P66.1.w1)
  • Data for 1,610 raccoons submitted for testing between 1st January 1982 and 20th September 1983, from the mid-Atlantic raccoon rabies focus states of Virginia, West Virginia and Maryland, found that for people potentially exposed to rabies through a raccoon, fox or skunk, in 17% of exposures, the potentially rabid animal had attacked the person. (J101.126.w1)
  • For rabid raccoons from the mid-Atlantic states during 1st January 1992 to 30th September 1983, 70% were aggressive, 64% overly friendly, 75% wobbly, 76% paralysed, 57% injured and 61% were first seen during the day. (J101.126.w1)
  • Rabid raccoons have been noted as aggressive, found out during daylight, sick, uncoordinated or paralysed. (B360.16.w16)
  • In New Jersey during a vaccination study, while 19 radio-collared raccoons moved a mean straight line distance of 1.5 +/- 0.5 km (range 0.8 - 2.58 km), five raccoons (including one radiocollared) trapped and ear tagged while clinically normal, and later diagnosed as rabid, had moved a mean of 8.4 +/- 4.5 km (range 1.9 - 12.9 km) and the maximum linear movement of the rabid raccoons was significantly higher (P = 0.001) than that of non-rabid collared raccoons in this area. Movements of 11.6 and 12.9 months in rabid raccoons had occurred in three and two months respectively. (J1.34.w8)
  • For rabid raccoons found at the National Zoological Park, Washington, D.C., May to October 1983, many rabid animals were found within mammal exhibits, which was unusual. Most of the raccoons appeared disorientated, some were ataxic and easily caught using a net. None were "on a rampage". One found in an enclosure of bushdogs (Speothos venaticus) had multiple bite wounds. (P103.1983.w1)
  • An adult female live-trapped, tagged and vaccinated, was noted to vocalise repeatedly with "high-pitched whining sounds". On recapture the following day at a site 1.7 km away, the raccoon was "very agitated - constantly moving back and forth in the live-trap, turning upside down repeatedly, vocalising with a high-pitched whine, and had three Porcupine, Erethizon dorsatum [Erethizontidae - New-world porcupines], quills in its facial area (snout)." (J435.119.w2)
  • Of raccoons with raccoon rabies variant in Ontario, Canada, 1999-2003, 29/125 (23.2%) were described as aggressive, 24/125 (19.2%) appeared sick or unhealthy, 14/125 (11.2%) had fought with a dog, 16/125 (12.8%) had abnormal vocalisations, 19/125 (15.2%) showed ataxia or impaired mobility and 16/125 (12.8%) were noted to be impaled with porcupine quills; 13/125 (10.4%) showed normal behaviour. (J1.42.w3)
  • In Canada, analysis of 199 to 2004 data for 1079 raccoons submitted for rabies testing noted that only three of 1038 rabies-negative raccoons submitted for rabies testing had quills embedded, while five of 41 rabies-positive individuals had quills; there was a highly significant (chi square = 75.97, P<0.0001) relationship between the presence of quills and the diagnosis of rabies. Quills were also found in two of 328 raccoons positive for canine distemper virus (including one raccoon positive for both viruses). (J14.48.w1)
Experimental infections
  • In five raccoons inoculated with 0.3 mL of a raccoon rabies isolate from a naturally infected raccoon from Pennsylvania (titre 105.8 MICLD50 per mL), sudden onset neurological signs were seen including combinations of circling, head-pressing, head-tilt, excess licking, mainly of the genital area and tail tip, and occasional self-mutilation of the limbs or genital area (in raccoons developing signs overnight while not observed). (J212.8.w1)
  • In a raccoon injected intramuscularly in the right hind leg with 0.2 ml of a skunk rabies isolate, the first signs were seen after 18 days, with increased activity, pacing and climbing the cage; food left in the cage was not eaten. At this stage an observer was ignored, as was a rod inserted into the cage. The following day, restlessness continued and human approach resulted in the raccoon charging the front of the cage, snarling, gnashing her teeth, flattening her ears and grabbing hold of and rattling the cage bars; these signs increased in intensity during through the day. By the following day, the raccoon repeatedly bit a rod when it was inserted into the cage. During the next three days, furious signs were greatest, and howling and growling were noted. The next day, the raccoon was less vocal but more aggressive and charges ended with the raccoon slamming into the bars rather than grasping them (possibly due to the start of incoordination). The next day (eighth day of signs), restlessness, irritability and aggression were no longer present; rather, the raccoon appeared friendly, licking a gloved hand placed on the cage. This friendly behaviour continued for a further two days. On the eleventh day the raccoon was obviously incoordinated, missing objects by several inches when reaching for them. In the following two days the raccoon showed rapidly alternating periods of aggression and friendliness, head and shoulder tremors, and increased incoordination, sometimes with howling and snarling. By the fourteenth day the raccoon had paralysed hindquarters; the following days the raccoon showed paralysis and prostration, and gentle behaviour. The raccoon died on the 17th day from the onset of the first signs. (J196.58.w1)
  • In raccoons experimentally infected with a street raccoon rabies variant (injected into the masseter muscle at 2 x 104 tissue-culture dose in 0.2 mL or 1 x 105 TCID50 in 1 mL), prodromal signs included reduction or cessation of eating and drinking. Clinical signs included hyperaesthesia to visual, auditory and tactile stimuli, pacing, increased aggression, increased vocalisation with a qualitative change in phonation, ptylism, gnashing of the teeth, scratching the face and head tilt. (J2.37.w1)
  • In a raccoon challenged with street rabies (105.5 MICLD50 strain MD5951) six months after oral vaccination with vaccinia-rabies glycoprotein recombinant (V-RG) vaccine, clinical signs included incoordination, paresis, recumbent paralysis "and other signs"; the raccoon recovered, such that when killed at 90 days after challenge there was only a residual head tilt. (J270.10S4.w2)
  • When raccoons were inoculated into the masseter muscle with 102.4, 103.4 or 104.8 MICLD50 of skunk rabies virus isolated from a naturally-infected Mephitis mephitis - Striped skunk, all survived an observation period of 92 days; one of the raccoons inoculated with the highest dose developed a tic, initially in the left fore, later developing into a bilateral twitch affecting both front legs and the shoulders, visible when the raccoon was sitting. It was not possible to determine whether or not this sign was associated with the rabies virus inoculation. (J1.28.w8)
  • Following inoculation of raccoons with 103.2 MICLD50 New York City/Georgia canine strain rabies virus (NYC/GA) from fox salivary glands ( a known lethal dose), into the masseter muscle, some raccoons showed no clinical signs prior to death. In those where signs were seen, the raccoons exhibited increased alertness or apprehension, for less that 24 hours, then aggression for a few hours before death. (J1.28.w8)
  • In five raccoons experimentally inoculated in the masseter muscle with a canine rabies virus isolate (MD5951, at 0.3 ml of culture with 106.9 MICLD50 per mL), raccoons developed vague signs of depression, anorexia and lethargy; one individual was found dead in the morning having been apparently normal the previous night. Animals were euthanased as soon as signs were seen, therefore no information was available on progression of clinical signs. (J212.8.w1)
Effects of different rabies virus strains:
  • It is possible that clinical signs of rabies may vary depending on the rabies variant infecting a raccoon, and that more severe clinical neurological signs may be seen in raccoons infected with raccoon rabies variant than in raccoons infected with other rabies variants. (J212.4.w1)

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Humans Homo sapiens - Human
 
General summary:
  • --
Body temperature:
  • --
Neurological signs:
  • Prodrome: unease, restlessness, apprehension and often a tingling sensation at the original site of entry of the virus. 
  • Both excitatory and paralytic forms of the disease may be seen. Hydrophobia is a classical sign. (B47)
Digestive signs:
  • --
Urinary signs:
  • --
Respiratory signs:
  • --
Ophthalmic signs:
  • --
Ear, nose and throat signs:
  • --
Dermatological signs:
  • --
Recovery and Convalescence:
  • --

LITERATURE REPORTS: 

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Chimpanzee Pan troglodytes - Chimpanzee
 
General summary:
  • In the single reported case, unexpected aggression, biting a caretaker; death several hours later. (J4.162.w2)
Neurological signs:
  • Unexpected aggression, biting a caretaker; death several hours later. (J4.162.w2)

LITERATURE REPORTS: 
  • Unexpected aggression, biting a caretaker; death several hours later. (J4.162.w2)

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 Domestic dog Canis familiaris - Domestic dog
 
General summary:
  • --
Neurological signs:
  • Prodrome: affectionate animals may shun company, nervous animals may seek company. Often not noticed. (B47)
  • Restlessness, nervousness, snapping at real/imaginary insects. Viciousness develops, initially directed towards strangers, later also to the owner (affected dogs no longer appear to recognise their owner). There may be excitation, photophobia and hyperaesthesia. Restrained individuals may chew vigorously on metal chains or bars, breaking teeth and lacerating the tongue and mouth. Ropy and sometimes bloody saliva is drooled, or rapid heavy respiration causes saliva to froth. Affected animals appear not to notice pain or discomfort and may swallow a variety of foreign objects including wood, stones, straw, faecal matter etc. No hydrophobia is present, unlike in humans. Phonation is altered due to partial laryngeal paralysis, resulting in strange howls and moans. The dog usually is not interested in food, but spastic attempts to swallow may occur. The animal may be unable to close the eyelids, in which case the cornea becomes dry and dull. Often pupillary dilatation occurs, resulting in a staring, "far away" look. This stage terminates in convulsive seizures and muscular incoordination. (B47)
  • High-pitched howling is common. (J15.23.w4)
Digestive signs:
  • The dog usually is not interested in food, but spastic attempts to swallow may occur. (B47)
Respiratory signs:
  • Respiration may be rapid and heavy. (B47)
Ophthalmic signs:
  • The animal may be unable to close the eyelids, in which case the cornea becomes dry and dull. Often pupillary dilatation occurs, resulting in a staring, "far away" look. (B47)
Ear, nose and throat signs:
  • Phonation is altered due to partial laryngeal paralysis, resulting in strange howls and moans. (B47)
  • High-pitched howling is common. (J15.23.w4)

LITERATURE REPORTS: 
  • Prodrome: affectionate animals may shun company, nervous animals may seek company. Often not noticed. (B47)
  • Restlessness, nervousness, snapping at real/imaginary insects. Viciousness develops, initially directed towards strangers, later also to the owner (affected dogs no longer appear to recognise their owner). There may be excitation, photophobia and hyperaesthesia. Restrained individuals may chew vigorously on metal chains or bars, breaking teeth and lacerating the tongue and mouth. Ropy and sometimes bloody saliva is drooled, or rapid heavy respiration causes saliva to froth. Affected animals appear not to notice pain or discomfort and may swallow a variety of foreign objects including wood, stones, straw, faecal matter etc. No hydrophobia is present, unlike in humans. Phonation is altered due to partial laryngeal paralysis, resulting in strange howls and moans. The dog usually is not interested in food, but spastic attempts to swallow may occur. The animal may be unable to close the eyelids, in which case the cornea becomes dry and dull. Often pupillary dilatation occurs, resulting in a staring, "far away" look. This stage terminates in convulsive seizures and muscular incoordination. (B47)
  • High-pitched howling is common. (J15.23.w4)

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Domestic cat Felis catus - Domestic cat
 
General summary:
  • Subtle behavioural changes during the prodrome, followed by neurological signs, usually with the furious form, including an unusual look in the eyes, unusual aggressiveness, abnormal gait, increased vocalisation etc. (B47, 4.202.w2, J15.23.w4)
Neurological signs:
  • Prodrome: affectionate animals may shun company, nervous animals may seek company. Often not noticed. (B47)
  • Signs may be similar to those seen in dogs. (B47)
  • Cats develop the furious form more commonly than do dogs. (J15.23.w4)
  • Signs noted in a study in Maryland (31 cats) included unusual aggressiveness (18 cats), an unusual look in the cat's eyes (anxious, staring, wild spooky or blank) (15 cats), abnormal gait (15 cats), usually wobbly or collapsing hind limbs, increased frequency of vocalisation (14 cats), less commonly (seven cats) a change in the cat's voice and sometimes (eight cats) partial or complete paralysis. Early signs included lethargy, anorexia, increased vocalisation frequency, increased nervousness, irritability or anxiety, trembling, vomiting and a strange look in the eyes. (J4.202.w2)
Ophthalmic signs:
  • Signs noted in a study in Maryland (31 cats) included an unusual look in the cat's eyes (anxious, staring, wild spooky or blank) (15 cats). Early signs included a strange look in the eyes. (J4.202.w2)
Ear, nose and throat signs:
  • Signs noted in a study in Maryland included a change in the cat's voice. Early signs included increased frequency of vocalisation. (J4.202.w2)

LITERATURE REPORTS: 
  • Prodrome: affectionate animals may shun company, nervous animals may seek company. Often not noticed. (B47)
  • Signs may be similar to those seen in dogs. (B47)
  • Cats develop the furious form more commonly than do dogs. (J15.23.w4)
  • Signs noted in a study in Maryland (31 cats) included unusual aggressiveness (18 cats), an unusual look in the cat's eyes (anxious, staring, wild spooky or blank) (15 cats), abnormal gait (15 cats), usually wobbly or collapsing hind limbs, increased frequency of vocalisation (14 cats), less commonly (seven cats) a change in the cat's voice and sometimes (eight cats) partial or complete paralysis. Early signs included lethargy, anorexia, increased vocalisation frequency, increased nervousness, irritability or anxiety, trembling, vomiting and a strange look in the eyes. (J4.202.w2)

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Snow leopard Uncia uncia - Snow leopard
 
General summary:
Neurological signs:

LITERATURE REPORTS: 

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Ferret Mustela putorius furo - Ferret (Species)
 
General summary:
  • The main signs in experimentally inoculated ferrets were neurological, including paresis to ascending paralysis, tremors, ataxia, bladder atony, inactivity/lethargy or hyperactivity, rarely aggressive behaviour. Other signs included anorexia, cachexia, constipation and fever or hypothermia. (J13.58.w1, J13.59.w1, J213.8.w3)
Body temperature:
  • Both fever and hypothermia may occur. (J13.58.w1, J13.59.w1, J213.8.w3) 
Neurological signs:
  • Experimentally inoculated ferrets developed neurological signs including:
    • Inactivity, paresis, paraparesis, paralysis, ascending paralysis, ataxia, tremors, hyperactivity, paresthesia, anorexia, cachexia, atony of the bladder, constipation, fever and hypothermia. Aggressive behaviour occurred uncommonly. (J13.59.w1, J213.8.w3) 
    • With raccoon rabies virus: ascending paralysis, ataxia, cachexia, atony of the bladder, hyperactivity, tremors, paresthesia and fever. (J13.58.w1)
Digestive signs:
  • Anorexia sometimes occurred. (J13.59.w1, J213.8.w3) 
  • Constipation was sometimes noted in experimentally infected ferrets. (J13.59.w1, J213.8.w3) 
Urinary signs:
  • Atony of the bladder sometimes developed. (J13.58.w1, J13.59.w1, J213.8.w3)
Recovery and Convalescence:
  • One ferret inoculated with rabies from a skunk developed clinical signs and recovered with severe paralytic sequelae.  (J13.58.w1)

LITERATURE REPORTS: 
  • In experimental infections with fox, raccoon and skunk rabies variants, the mean incubation period was about a month. Clinical signs included ascending paralysis, ataxia, tremors, hyperactivity, paresthesia, anorexia, cachexia, atony of the bladder, constipation, fever and hypothermia. Aggressive behaviour occurred uncommonly. In ferrets inoculated with European fox rabies, signs were mild. Mortality was dose-dependent in ferrets inoculated with the fox or skunk strains, but not with the raccoon strain. (J213.8.w3) 
  • In experimentally inoculated ferrets, after an incubation period of 16 - 96 days (mean 33 days), ferrets developed clinical signs including ascending paralysis, ataxia, cachexia, atony of the bladder, hyperactivity, tremors, paresthesia and fever. Clinical signs lasted about four to five days. Ferrets were euthanised if they developed severe clinical signs, but others survived and seroconverted. One survivor developed clinical signs and recovered with severe paralytic sequelae. From one of the euthanased ferrets, rabies virus was recovered from the salivary gland. Virus antigen was detected in the brain tissue of all individuals which developed clinical rabies. Some of the euthanased ferrets had seroconverted. (J13.58.w1)
  • In ferrets experimentally inoculated with raccoon rabies virus, 19/51 developed clinical signs after 17 - 63 days (mean 28 days) and were euthanised after 1 - 8 days (mean 4-5 days). Signs included ataxia, cachexia, inactivity, paresis, paraparesis, paralysis, atony of the bladder, tremors, lethargy, hypothermia, constipation and anorexia. Two of these ferrets had detectable virus neutrlising antibodies. Rabies virus antigen was detected in the brains of all these ferrets. Only one of the survivors (all of which remained clinically normal) seroconverted. In 12/19 rabid ferrets, virus was recovered from the salivary glands, with nine (47%) shedding virus in saliva; virus excretion began as early as two days before illness onset to as late as six days after the onset of clinical signs. (J13.59.w1)

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Bears Ursidae - Bears (Family)
 
General summary:
  • Paralysis or aggression. (B336.51.w51)

Neurological signs:

LITERATURE REPORTS: 
  • In an Ursus maritimus - Polar bear:

    • Posterior paralysis. (J1.27.w9)

  • In Ursus americanus - American black bear:

    • Unusual aggression, with an attack on an alpaca, eating it alive, followed by an unprovoked attack on a woman near her house. (N20.12.w3)

    • One bear was found out of the den early (April 1) and the landowner claimed that is appeared to be stalking him. (J14.37.w3)

    • One bear (April 25th) approached close to (within two metres) a woman while she was getting out of her car one night (about 2300 hrs) then, having been driven off by the woman's dogs, followed the dogs to their home. (J14.37.w3)

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Domestic horse Equus caballus - Domestic horse
 
General summary:
  • --
Neurological signs:
  • Signs are very variable. Rubbing and biting at the wound site may be the first sign. The affected horse is often alert and tense, with its ears held erect and moving backwards and forwards quickly as if listening to sounds from different directions. There may be evident genital excitement. The affected animal may try to break, or to bite through, a rope tying it, and may attack its manger sufficiently vigorously that it breaks its own teeth or jaw. Pawing the ground with the front feet and kicking out with the hind feet may be seen. Food is generally refused but the horse may swallow objects such as straw, wood and manure. Other neurological signs which may be seen include hyperaesthesia, ataxia, paralysis, behavioural signs and seizures. Fever may be noted. Paralysis generally affects the throat first with the horse becoming unable to swallow water; saliva drools from the lips, then the animal develops locomotor difficulties and finally becomes recumbent with death occurring within a few hours. A series of violent convulsions may precede death. (B47)
Digestive signs:
  • Food is generally refused but the horse may swallow objects such as straw, wood and manure. (B47)
  • Saliva drools from the lips due to inability to swallow. (B47)
Ear, nose and throat signs:
  • Paralysis generally affects the throat first with the horse becoming unable to swallow water; saliva drools from the lips. (B47)
Dermatological signs:
  • Rubbing and biting at the wound site may be the first sign. (B47)

LITERATURE REPORTS: 

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Domestic cattle Bos taurus - Domestic cattle
 
General summary:
  • --
Neurological signs:
  • Signs early in the disease are often vague and confusing. If the furious form is manifest then bellowing is noted, which may be incessant and show an altered pitch to the voice. The animal also paws the ground and may attack humans or other animals if provoked. More commonly there are no signs of excitement. Some but not all affected animals will show drooling at the mouth; this depends on whether or not pharyngeal paralysis occurs. A wide open stare and fixed gaze following any moving object are noted. Affected animals are anorectic and milking animals show abrupt cessation of lactation. Knuckling of the hind fetlock joints is common, as is almost continuous straining, often with air aspirated into the rectum when the animal temporarily relaxes. Often the tail is paralysed and bulls may show flaccid protrusion of the penis. (B47)
Mammary signs:
  • Milking cows show abrupt cessation of lactation. (B47)
Reproductive signs:
  • Bulls may show flaccid protrusion of the penis. (B47)

LITERATURE REPORTS:

Bos taurus - Domestic cattle:

  • Signs early in the disease are often vague and confusing. If the furious form is manifest then bellowing is noted, which may be incessant and show an altered pitch to the voice. The animal also paws the ground and may attack humans or other animals if provoked. More commonly there are no signs of excitement. Some but not all affected animals will show drooling at the mouth; this depends on whether or not pharyngeal paralysis occurs. A wide open stare and fixed gaze following any moving object are noted. Affected animals are anorectic and milking animals show abrupt cessation of lactation. Knuckling of the hind fetlock joints is common, as is almost continuous straining, often with air aspirated into the rectum when the animal temporarily relaxes. Often the tail is paralysed and bulls may show flaccid protrusion of the penis. (B47)

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Domestic sheep/goats Ovis aries - Domestic sheep/Capra hircus - Domestic goat
 
Neurological signs:
  • Restlessness, excitement and aggression may be seen, also increased sexual activity - frequent mounting. (B47, B416.44.w44)
Digestive signs:
  • Licking the lips may be seen. (B416.44.w44)
  • Pica may occur. (B47)
Respiratory signs:
  • Dyspnoea may be seen. (B416.44.w44)
Ophthalmic signs:
  • " a wild and staring gaze" (B47)
Dermatological signs:
  • Signs can include pruritis. (B47)

LITERATURE REPORTS: 
  • Signs "can include restlessness, excitement, twitching of the lips, a wild and staring gaze, pruritis, pica, genital excitement, depression and terminal paralysis." (B47)
  • Restlessness and aggression, dyspnoea, licking the lips and increased sexual activity - frequent mounting. (B416.44.w44)

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Domestic pig (swine) Sus domesticus - Domestic pig
 
Neurological signs:
  • Initially irritative, easily frightened, root at the ground and rub/gnaw at the injury site. Later the pig may become very aggressive and bite other animals or humans. Usually develop paralysis and die within two to four days. (B416.44.w44)
Dermatological signs:
  • Initially may and rub/gnaw at the injury site. (B416.44.w44)

LITERATURE REPORTS: 
  • Similar to signs in sheep and goats. (B47)
  • Initially irritative, easily frightened, root at the ground and rub/gnaw at the injury site. Later the pig may become very aggressive and bite other animals or humans. Usually develop paralysis and die within two to four days. (B416.44.w44)

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Elephants Elephas maximus - Asian Elephant
 
Neurological signs:
Paralytic rabies
  • Lethargy. (J12.9.w1)
  • Developing anorexia. (J3.144.w2, J12.9.w1)
  • Paralysis of the trunk. (J3.144.w2, J12.9.w1, J12.61.w1)
  • Paralysis of the limbs; recumbency. (J3.144.w2, J12.9.w1, J12.61.w1)
  • Blindness. (J3.144.w2)
  • Involuntary defecation. (J12.61.w1)
  • Death nine days after the onset of lethargy (J3.144.w2); death nine days after the first sign (lameness). (J12.9.w1)

Furious rabies

  • Severe restlessness, trembling, twitching and the elephant trying to break away, subsequently unable to swallow food or water, aggressive. (B212.w41)
  • One calf butted and kicked at imaginary objects, screaming and uttering other unusual sounds. (B212.w41)
Dermatological signs:
  • Secretion from the temporal glands. (J3.144.w2)

LITERATURE REPORTS: 

Elephas maximus - Asian Elephant:

Paralytic rabies
  • Lethargy. (J12.9.w1)
  • Developing anorexia. (J3.144.w2, J12.9.w1)
    • Normal eating and drinking initially; anorectic by the sixth day. (J3.144.w2)
    • Difficulty in swallowing food or water. (J12.61.w1)
  • Secretion from the temporal glands. (J3.144.w2)
  • Paralysis of the trunk. (J3.144.w2, J12.9.w1, J12.61.w1)
  • Paralysis of the limbs; recumbency. (J3.144.w2, J12.9.w1, J12.61.w1)
    • Falling when attempting to stand, and recumbency. (J3.144.w2)
    • Lateral recumbency with only feeble hind leg and tail reflexes. (J12.61.w1)
    • Hind limb lameness progressing to paresis, difficulty in standing up and finally paralysis. (J12.9.w1)
  • Blindness developing by day six. (J3.144.w2)
  • Involuntary defecation. (J12.61.w1)
  • Death nine days after the onset of lethargy (J3.144.w2); death nine days after the first sign (lameness). (J12.9.w1)

Furious rabies

  • In elephants in Burma, furious rabies has been described: early signs noted were severe restlessness, trembling, twitching and the elephant trying to break away. Subsequently, individuals became unable to swallow food or water and showed aggression. One calf was described as butting and kicking at imaginary objects, screaming and uttering other unusual sounds. Death occurred after seven days in the calf and after perhaps five days [data unclear] in one of the other cases. (B212.w41)
  • A description is available in Elephants and their Diseases- A Treatise on Elephants - Part V - Chapter VIII - Rabies. Tetanus. Tuberculosis. Full text included.

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Laboratory mouse Mus domesticus - Laboratory mouse
 
Neurological signs:
  • In experimentally infected laboratory mice, muscle tremors and gait incoordination, developing to terminal paralysis and death. Other signs may include ruffled fur, an arched back and flaccid paralysis of the limbs. (B416.44.w44)
Ophthalmic signs:
  • In experimentally infected laboratory mice conjunctivitis is sometimes noted. (B416.44.w44)
Dermatological signs:
  • Ruffled fur may be seen. (B416.44.w44)

LITERATURE REPORTS: 
  • In experimentally infected laboratory mice: muscle tremors, gait incoordination, developing to terminal paralysis and death. Other signs may include ruffled fur, arched back, flaccid paralysis of the limbs and sometimes conjunctivitis. (B416.44.w44)

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Rabbits and Hares (Lagomorphs)  
 
Neurological signs:

Rabbits will usually develop the paralytic form of disease; the furious form is unusual in rabbits. (B602.20.w20)

Initial clinical signs are non specific including:

The disease may then progress to:

  • Mandibular and laryngeal paralysis with a dropped jaw. (B609.2.w2)
  • Inability to swallow (B609.2.w2)
  • Hypersalivation (B609.2.w2)
  • Blindness (B602.20.w20)
  • Posterior paresis. (B609.2.w2)
  • Paralysis of one or more limbs; 
    • Paralysis of the forelimbs has been reported in the rabbit. (B601.11.w11, B602.20.w20, B603.3.w3, B606.13.w13, J4.179.w6)
  • Coma and death. (B601.11.w11)
Clinical pathology:
  • There are no characteristic biochemical or haematologic changes. (B609.2.w2)

LITERATURE REPORTS: 

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Hedgehog Atelerix algirus - Algerian hedgehog
 
Neurological signs:
  • Paralysis. (J137.93.w1)

LITERATURE REPORTS: 

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Birds Aves - Birds
 
Neurological signs:
  • Short aggressive period may include jumping, crying, trying to flee, aggression to humans, epileptiform convulsions. 
  • Later (24 hours after), ataxia, weakness, falling. 
  • Progresses to flaccid paralysis, and by two weeks after first signs somnolence, apathy, compulsive movements and death.

LITERATURE REPORTS: 
  • May remain asymptomatic. Short aggressive period, may include jumping, crying, trying to flee, aggression to humans, epileptiform convulsions. Later (24 hours after), ataxia, weakness, falling. Progresses to flaccid paralysis, and by two weeks after first signs somnolence, apathy, compulsive movements and death.
  • Spontaneous recovery may occur.

(B12.55.w1, B13.32.w3).

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Domestic poultry Gallus gallus - Red junglefowl
 
Neurological signs:
  • Fear, wild running with ruffled feathers, a hoarse cry, aggression - attacking other birds, mammals and humans, development of ataxia, frequent falling, development of paralysis and death after two to three days. (B416.44.w44)
Ear, nose and throat signs:
  • A hoarse cry may be noted. (B416.44.w44)

LITERATURE REPORTS: 
  • Fear, wild running with ruffled feathers, a hoarse cry, aggression - attacking other birds, mammals and humans, development of ataxia, frequent falling, development of paralysis and death after two to three days. (B416.44.w44)

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