Guidance

Rabies: epidemiology, transmission and prevention

Information and advice on rabies, the viral infection of the central nervous system which affects mammals and humans.

Rabies is an infection of the central nervous system caused by the rabies virus, a member of the rhabdovirus family. Worldwide, it is estimated that there are in excess of 59,000 human cases of rabies each year, almost entirely in developing countries.

Rabies in animals worldwide

Rabies virus infects a variety of mammals in many parts of the world, particularly in Asia and Africa. (See PHE rabies country listing).

Dogs and cats, due to their high level of contact with the human population and propensity to bite, are the main risk to humans. Bats may also carry rabies and rabies-like viruses, even in countries which are declared rabies-free in terrestrial animals.

Rabies in animals in the UK

In the UK, rabies has been eliminated from terrestrial animal populations. The last rabid terrestrial animal in the UK was a puppy in quarantine which had been imported from Sri Lanka and found to be rabid in 2008.

Rabies affects bats as well as terrestrial animals, and rabies-like viruses have been found in bats in the UK. These viruses are known as European Bat Lyssaviruses (EBLVs), types 1 and 2. They very rarely cross the species barrier from bats to humans and are different from the ‘classical’ rabies virus found in dogs and other animals. These viruses do however cause clinical rabies in humans.

The presence of EBLV does not alter the status of the UK as rabies-free.

EBLVs are found more commonly in bats elsewhere in Europe than the UK. There have only been 4 documented cases of transmission of EBLVs to humans in Europe from bats.

Human rabies in the UK

Human rabies is extremely rare in the UK. The last case of classical rabies acquired in this country was more than a century ago, in 1902. Cases occurring since then have all been acquired abroad, usually through dog bites.

Since 1946, 25 cases have been reported in the United Kingdom, all imported. Five cases occurred between 2000 and 2017:

  • two in 2001 from the Philippines and Nigeria

  • one in 2005 followed a dog-bite in Goa

  • one in 2008 resulted from a dog bite in South Africa

  • one in 2012 developed after a dog bite in India

In 2002 a man who was a licensed bat handler died in Scotland from infection with EBLV-2, a rabies-like virus present in bats in the UK.

Transmission of rabies

Humans generally catch rabies through being bitten or scratched by an infected animal (usually a dog). Human rabies cases in the UK between 2000 and 2017 were all associated with exposure to infected animals elsewhere in the world. None of these cases were known to have received pre-or post-exposure rabies treatment.

Despite there being tens of thousands of rabies cases each year worldwide, there has never been a laboratory-documented case of human-to-human transmission, other than a very few cases resulting from organ or tissue transplant.

Despite the lack of evidence for human-to-human transmission, people who are identified as contacts of a patient with rabies will sometimes be offered immunisation, purely as a precautionary measure.

Spread of rabies by kissing or intimate contact remains a theoretical route of transmission that has never been laboratory confirmed. However, rabies virus can be found in saliva and other body fluids after the onset of rabies symptoms and clinical disease, so there is a small theoretical risk of infection at this stage of disease.

This is why close contacts of rabies cases are risk assessed, and post exposure treatment may be offered depending on the exposure.

Symptoms and signs of rabies in humans

The incubation period from the bite to onset of symptoms is generally between 3 and 12 weeks but is very variable. In some cases, incubation periods have been several months or even years.

Rabies is a very serious infection which affects the central nervous system. It can be difficult to diagnose in the early stages as symptoms may be non-specific (which are common to many infections).

Initial symptoms can include anxiety, headaches and fever. Subsequently, there are spasms of the swallowing muscles making it difficult or impossible for patients to drink (hydrophobia), and respiratory failure sets in.

Prevention of rabies

Rabies is a fatal condition but it is preventable by vaccination. Post-exposure treatment is extremely effective at preventing rabies after being bitten when started promptly. Once clinical rabies develops, it is almost always fatal.

It is important for people who are at risk through their work or who are travelling to countries where rabies is circulating in animals to seek advice on vaccination, as directed in the Green Book:

a) pre-exposure immunisation for those within the UK

  • laboratory staff routinely working with rabies virus

  • workers at Defra-authorised quarantine premises and carriers

  • those who regularly handle bats, including on a voluntary basis, in the UK

  • veterinary and technical staff who, by reason of their employment, encounter enhanced risk

b) pre-exposure immunisation for those travelling outside the UK

  • animal control and wildlife workers, veterinary staff or zoologists who regularly work in rabies enzootic areas
  • travellers to rabies enzootic areas, especially if post-exposure medical care and rabies biologics at the destination are lacking or in short supply, or they are undertaking higher risk activities such as cycling or running, or they are living or staying for more than one month

Advice for travellers

  • seek advice before travel about whether rabies vaccine is required

  • when travelling, stay away from stray or unattended animals

  • if bitten or scratched in a country where rabies is present, clean the wound thoroughly with soap and plenty of water and seek local medical advice immediately

  • do not wait until return to the UK before being assessed and starting rabies vaccination if needed

  • contact your GP on returning home to ensure rabies post-exposure treatment can be completed

  • if treatment is not obtained at the time of the bite/scratch, seek medical advice immediately on return, even if the bite was weeks before.

Health professionals can seek advice from PHE - see rabies collection and the PHE rabies and immunoglobulin service

The Department of Health Green Book rabies chapter has details of rabies pre-exposure prophylaxis and post-exposure treatment.

Further information

Rabies in bats

NaTHNaC rabies factsheet

Rabies on NHS.UK

Published 2 November 2018