Control of Neglected Tropical Diseases
We coordinate and support policies and strategies to enhance global access to interventions for the prevention, control, elimination and eradication of neglected tropical diseases, including some zoonotic diseases.
Learn more

Animal rabies

Rabies

 

Transmission of animal rabies is similar to that of human rabies, with virus-laden saliva from infected animals entering the body through wounds or by direct contact with mucosal surfaces. Following access to the muscle cells at the wound site, peripheral nerves and subsequently the central nervous system, the virus travels retrogradely from the CNS via peripheral nerves to various tissues, most importantly the salivary glands, from which it is shed, completing the transmission cycle.

Though the major burden of human rabies is attributed to dog-mediated transmission, a wildlife (sylvatic) cycle of rabies also exists, with wild animals (e.g. bats, raccoons and foxes) serving as the maintenance host of the virus.

Dog rabies is characterized by clinical manifestations, including changes to normal behaviour, such as:

  • Biting without provocation
  • Eating abnormal items such as sticks, nails, faeces, etc.
  • Running for no apparent reason
  • Vocal changes (e.g. hoarse barking and growling) or inability to produce sounds
  • Excessive salivation or foaming from the mouth

 

Investment in eliminating the risk of rabies at its source is the most cost-effective measure. Vaccination of at least 70% of dogs in areas at risk is now accepted as the most effective way of preventing human rabies deaths. However, in many parts of Asia and Africa the vaccination coverage (of generally 30-50%) established in dog populations is not high enough to break the transmission cycle of the disease and early discontinuation of rabies control programmes can lead to costly re-emergence of the disease.

 

 

Dog rabies control

More than 3 billion people, about half the world’s population, are living in countries/territories where dog rabies still exists and are potentially exposed to rabies. It is estimated that at least 59 000 human rabies deaths occur yearly in Africa and Asia following contact with rabid dogs.

In many of those countries, few activities are underway to prevent rabies occurrence in humans and to control rabies in dogs, even when the number of human deaths is high. This is the case in, for example, Bangladesh, Cambodia, India, Laos, Nepal, and Pakistan in Asia, as well as most African, east Mediterranean, and Arabic peninsular countries. On the other hand, some countries report having improved their post-exposure treatment delivery systems in conjunction with significant activities for dog rabies control.

In some countries these activities have led to a sustainable reduction in dog rabies as previously reported for Thailand, as well as South Africa, Iran, and especially in some Latin American countries. In other countries (e.g., Morocco, Sri Lanka, and Tunisia) these activities have led to containment of the rabies situation. WHO promotes activities for the control and elimination of dog rabies particularly in Asia and Africa. A number of WHO documents dealing with the various aspects of a comprehensive dog rabies control programme have been developed over time.

 

Controlling rabies in dogs: what to do - what to avoid doing?

Further to recent reports indicating that indiscriminate mass culling of dogs is still used in certain countries as the principal measure to combat dog rabies and prevent associated human rabies. The WHO wishes to reiterate the recommendations of the Expert Consultation on Rabies held in Bangkok, 26–28 April 2017 (WHO Expert Consultation on Rabies: WHO TRS N°1012, Third report):

  • Dog destruction alone is not effective in rabies control. There is no evidence that removal of dogs alone has ever had a significant impact on dog population densities or the spread of rabies. In addition, dog removal may be unacceptable to local communities. However, the targeted and humane removal of unvaccinated, ownerless dogs may be effective when used as a supplementary measure to mass vaccination.
  • Mass canine vaccination campaigns have been the most effective measure for controlling canine rabies. High vaccination coverage (70% or higher) can be attained through comprehensive strategies consisting among others of well-designed educational campaigns, intersectoral cooperation, community participation, local commitment in planning and execution.
  • Surveillance of rabies is the basis for any programme of rabies control. Veterinary surveillance of rabies and laboratory submission of reports of suspected animal cases is also essential for management of potential human exposures and for veterinarians to adopt appropriate measures towards animals in contact with a suspected animal case.
  • Efforts should be made to fully incorporate rabies control activities in all levels of the health services, aligning them with other public health programmes such as the Expanded programme on immunization and those for tuberculosis and vector-borne diseases. In this manner, synergies between programmes improve logistical use of human, material and financial resources.