Introduction

Classification

Taxonomy

• Family: Rhabdoviridae.
• Genus: Lyssavirus.
• RNA virus.

Etymology

• Gk: rhabdos - rod; refers to the shape of the virus. Often described as bullet-shaped; lyssa - rage, fury.

Active Forms

Clinical Effects

Epidemiology

Habitat

• Important reservoir hosts are foxes, skunks, wolves, raccoons, mongoose, coyotes and bats, depending on region. These animals carry infectious viruses in their salivary glands and nerves.

Lifecycle

• Following transmission (usually by biting), rabies virus persists in local muscle tissue for hours or days.
• Initial replication may occur in muscle cells.
• Virus is taken up by motor nerve endings and spreads to the CNS, where further replication occurs.
• Virus then spreads to other organs, eg salivary glands, cornea and tonsils.

Transmission

• Saliva: bites from infected animals.
• Unlikely modes of transmission include transplants, sexual transmission.

Pathological effects

• Rabies Rabies disease.

Control

Control via animal

Quarantine

• Strict 6 month period of quarantine of animals when imported into rabies-free countries from countries where rabies is endemic.
• Elimination of stray dogs and cats and immunization of all mammalian pets with live attenuated virus or inactivated vaccine to control urban rabies in countries where rabies is endemic.
• The Rabies (Importation of Dogs, Cats and Other Mammals) Order 1974 prohibits entry of rabies-susceptible animals into Great Britain unless issued with an import licence by APHA (Animal and Plant Health Agency).
• The Non-Commerical Movement of Pet Animals Order 2011 states that pet dogs, cats and ferrets are not subject to the requirements of the Rabies (Importation of Dogs, Cats and Other Mammals) Order 1974, providing the following rules are adhered to:
  • The pet cat, dog or ferret has a microchip.
  • The pet, cat or ferret has a pet passport.
  • The pet cat, dog or ferret has been vaccinated against rabies and require a blood test if traveling from an unlisted country.
  • Dogs must also have tapeworm treatment.
• Quarantine up to 4 months at the owner's expense is required if the above rules are not followed.

Control via environment

• Vaccine-containing baits have been shown to be effective in controlling rabies in foxes in areas of Europe, also in wildlife in USA.

Vaccination

• Vaccination of mammalian pets in countries where rabies is endemic.
• Oral immunization of wildlife in some European countries has been successful.
• New regulations to be put in place in the USA will require blood-testing, vaccination and identification of animals imported from certain countries.
• Such vaccination must take place at at least 3 months of age, using inactivated and adjuvanted rabies vaccine.
• Vaccination must be boosted at least annually.
• Success of vaccination will be checked using a blood test; animals must show a rabies antibody titer ≥ 0.5 IU/ml.

Diagnosis

Further Reading

Publications

Refereed papers

• Recent references from PubMed and VetMedResource.
• Baer G M (1997) Evaluation of an animal rabies vaccine by use of two types of potency test. Am J Vet Res 58 (8), 837-840 PubMed.
• Delgado S & Cármenes P (1997) Immune response following a vaccination campaign against rabies in dogs from northwestern Spain. Preventive Vet Med 31 (3-4), 257-261 PubMed.
• Fu Z F (1997) Rabies and rabies research - past, present and future. Vaccine 15 (Suppl), S20-24 PubMed.
• Tepsumethanon V, Lumlertdacha B, Mitmoonpitak C et al (1997) Fluorescent antibody test for rabies: prospective study of 8, 987 brains. Clinical Infectious Diseases 25 (6), 1459-1461 PubMed.

Other sources of information

• The DEFRA website (www.gov.uk/government/organisations/department-for-environment-food-rural-affairs) provides details of the recent reappraisal of rabies and quarantine regulations.
• www.gov.uk/take-pet-abroad.