Rabies is an acute and usually fatal virus-related disease of mammals and humans.

The rabies virus is spread worldwide, only some islands (e.g. Great Britain, New Zealand) are free of rabies. The disease is particularly common in Africa, Asia and large parts of South America.

Dogs, foxes, tanuki, coyotes, raccoons and mongooses. Theoretically, however, all mammals as well as humans can become infected with the rabies virus. Bats are considered a reservoir for certain strains of lyssavirus.

The pathogen is transmitted through the saliva of infected animals, in most cases through a bite. However, in rare cases, the virus can also use uninjured mucous membranes and abrasions as a port of entry when direct contact with saliva occurs.

2 to 12 weeks (in exceptional cases up to one year), depending on the bite site

Altered behaviour, shyness, nervousness, irritability, difficulty swallowing, salivation, hydrophobia (aversion to water), increasing aggressiveness, signs of paralysis. Rabies almost always leads to death within 14 days after the onset of the disease.

There is no therapy

Rabies is incurable, but preventable. Regular vaccination of dogs and oral vaccination of reservoir animals can largely prevent human infections. Prophylactic vaccination (pre-exposure prophylaxis) is recommended for travellers to countries with a high rabies risk. In the event of a bite by a suspect animal, postexpositive prophylaxis (PEP) with administration of immunoglobulins and active immunisation are carried out.

The last human death due to wildlife-transmitted silvatic rabies was recorded in Carinthia in 1979 after a fox bite. An imported rabies death in Austria was last documented in 2004: a man died after being bitten by a rabid dog in Morocco. Austria was declared free of terrestrial rabies (= rabies in terrestrial animals) in 2008. The last time a fox was diagnosed with rabies was in 2004 and 2006. However, further investigations revealed that the virus was a vaccine virus that had been ingested by young animals. Prior to this, an animal rabies outbreak occurred in Carinthia in 2002 due to an immigration of foxes from Slovenia. The circulation of rabies virus in the Austrian dog population has been extinct since 1950.

Bat rabies is an independent infectious event and is not related to terrestrial rabies. It has not yet been observed in Austria in bats or other animals as well as humans.

Rabies surveillance in Austria

The current Austrian surveillance program is based on an EFSA study that recommends passive rabies surveillance - especially in rabies-free countries. Since 2013, only so-called "indicator animals" - i.e. foxes, badgers, raccoon dogs and raccoons found dead or killed in road traffic, as well as all animals suspected of being rabid (confirmation by the official veterinarian required) - have been tested for rabies. In Austria, oral vaccination of the fox population - in which, in contrast to the active vaccine used in human medicine, a live vaccine rather than an inactivated vaccine is used - was already discontinued in 2012.

Terrestrial rabies was detected in Austria's neighboring countries in 2022 in Hungary (4 cases) and Slovakia (2 cases). These cases all occurred near the border with Ukraine and were probably introduced by rabid animals from Ukraine. In Ukraine, terrestrial rabies occurs endemically.

Rabies viruses belong to the family Rhabdoviridae, genus Lyssavirus. A total of 17 different rabies virus species are currently distinguished. Another isolate is in the stage of verification whether it is a distinct virus species.

According to the World Health Organization (WHO), approximately 55,000 - 60,000 people are infected with the rabies virus each year, with dogs acting as carriers in most cases. Nearly half of the people bitten by rabies-infected dogs are children under the age of 15. In Austria, the last human fatality due to wildlife-transmitted silvatic rabies was recorded in 1979 in Carinthia following a fox bite. An imported rabies death in Austria was last documented in 2004: a man died after being bitten by a rabid dog in Morocco.

Rabies can occur in three different forms, depending on the host animal:

Urban rabies: Dogs are the main reservoir and transmit the rabies virus to other animals and humans. The circulation of the rabies virus in the Austrian dog population has been extinct since 1950.

Silvatic rage: It is a rabies transmitted by wild carnivores. The main reservoir in Europe is the red fox, in Eastern Europe additionally the raccoon dog. Since 2007, no rabies virus has been detected in wild animals in Austria.

Bat rabies: Bat rabies is an independent infection and is not related to silvatic rabies. It has not yet been observed in Austria in bats or other animals as well as humans.

The pathogen is transmitted through the saliva of infected animals, in most cases through a bite. However, in rare cases, the virus can also use uninjured mucous membranes and abrasions as a portal of entry when direct contact with saliva occurs. Contact with blood, urine, or feces of an infected animal, or touching or petting diseased animals alone, do not pose a risk of infection.

Controversially, exposure to bats in their habitats (caves with large bat populations) is a relevant risk for possible aerogenic transmission. The mere presence of a bat in the same room is not sufficient for transmission of the pathogen. Direct contact with bats, on the other hand, poses a risk of infection.

Some cases of human-to-human transmission have been published. The main cause in this context is transplantation. Individual cases of human-to-human transmission through bites have also been reported. Transmission in the context of caring for patients has not yet been observed.

Course of the disease

Rabies almost always leads to death within 14 days of onset. The time between the bite and the appearance of the first symptoms depends on the bite site. The farther the bite site is from the central nervous system, the longer it takes for the first symptoms to appear. Depending on whether a strong excitation stage or only paralysis symptoms characterize the clinical picture, a distinction is also made between raging and silent rage.

The classical course of the disease includes three stages:

Stage prodromal (prodromal stage): Nonspecific symptoms, such as signs of a flu-like infection, pain, itching, or paresthesias (sensations of discomfort) in the area of the bite wound

Irritation stage (excitation stage): Approximately 80% of patients develop the classic form of rabies ("raging rage"). This is characterized by episodes of confusion, agitation, and aggressive behavior alternating with periods of clear consciousness. Fever, increased salivation, sweating, dilated pupils, and goose bumps have also been described. Seizures occur rarely, usually in the advanced course of the disease. The majority of patients develop hydrophobia, characteristic of rabies. Flaccid paresis, coma, and multiple organ failure eventually occur.

Stage paralyticum (paralytic stage): In the paralytic stage of Rabies ("silent rage," about 20% of cases), flaccid paralysis occurs early and, as the disease progresses, pain, sensory disturbances, and autonomic dysregulation occur. Hydrophobia is rather atypical in this course, but may occur. Death eventually occurs due to paralysis of the respiratory muscles.

Rabies Outreach Center

The Rabies Advisory Service at the AGES Institute of Medical Microbiology and Hygiene Vienna offers professional information and advice for doctors and patients on the rabies situation in Austria and abroad, as well as in cases of emergency, including advice on indications for rabies vaccination after a bite wound by an animal suspected of being rabid, and for long-distance travelers on the basis of WHO recommendations. The consultation takes place 365 days a year through the personal presence of a human physician (Tel: +43 50 555-37111).

Austria was declared free of terrestrial rabies in 2008. The last time a fox was diagnosed with rabies was in 2004 and 2006. However, further investigations revealed that it was a vaccine virus that had been picked up by young animals. Prior to this, an animal rabies outbreak occurred in Carinthia in 2002 due to an immigration of foxes from Slovenia.

The circulation of rabies virus in the Austrian dog population has been extinct since 1950. Since 2007, no rabies virus has been detected in wild animals either. A case of rabies (dog) in the context of an illegal import of domestic animals last occurred in Austria in 1999.

Dogs and cats normally excrete rabies viruses in their saliva only in the final stages of the disease. It is extremely unlikely that they will exhibit normal behavior at this stage. Contact with blood, urine, or feces of an infected animal, or touching or petting diseased animals alone, does not pose a risk of infection.

Rabid bats are often found lying on the ground. They show abnormal behavior patterns, attack nearby objects, have orientation difficulties as well as signs of paralysis. Rabies-infected bats change their habits, become diurnal, and are found in places where they do not normally spend time.

Course of the disease in animals

Prodromal stage (Prodromal stage): Dejection, fever, nausea, reluctance to eat, vomiting, hydrophobia.

stage irritationis (excitation stage): excitement, hyperactivity, aggressiveness, salivation

Stage paralyticum (paralysis stage): Paralysis, impairment of the sensorium, coma.

Rabies vaccination of pets

Since the introduction of the EU pet passport, rabies vaccination has become even more important. The EU pet passport is a uniform animal passport in English and in the respective national language for dogs, cats and ferrets. It replaces all previous border formalities with regard to the EU countries and facilitates travel with animals within the EU.The EU pet passport valid for entry and exit must contain the rabies vaccination and the unique identification of the animal (tattoo or microchip).

A blood test with determination of the rabies titer is required as proof of sufficient rabies vaccination protection. This must be at least 0.5 IU/ml (IU = International Units) and indicates the concentration of antibodies in the blood. The rabies titer determination may only be performed in an EU-approved laboratory. In Austria, this is the AGES Institute for Veterinary Investigations Mödling.