Rabies is a vaccine-preventable, zoonotic, viral disease affecting the central nervous system. In up to 99% of the human rabies cases, dogs are responsible for virus transmission. Children between the age of 5 and 14 years are frequent victims.
Rabies infects mammals, including dogs, cats, livestock and wildlife.
Rabies spreads to people and animals via saliva, usually through bites, scratches, or direct contact with mucosa (e.g. eyes, mouth, or open wounds). Once clinical symptoms appear, rabies is virtually 100% fatal.
The global cost of rabies is estimated to be around US$ 8.6 billion per year including lost lives and livelihoods, medical care and associated costs, as well as uncalculated psychological trauma.
Rabies is present on all continents except Antarctica. Globally there are an estimated 59 000 deaths from rabies annually; however, due to underreporting, documented case numbers often differ from the estimate.
Rabies, a neglected tropical diseases (NTD), predominantly affecting marginalized populations. Although effective human vaccines and immunoglobulins exist for rabies, these are often inaccessible or unaffordable to those in need.
As of 2018, the average estimated cost of rabies post-exposure prophylaxis (PEP) was US$ 108 (along with travel costs and loss of income), which can be a financial burden on those earning US$ 1–2 per person, daily.
Over 29 million people worldwide receive human rabies vaccine annually.
In the Americas, where dog-mediated rabies is mostly controlled, hematophagous (blood-feeding) bats are now the primary source of human rabies. Bat-mediated rabies is also an emerging public health threat in Australia and parts of western Europe.
Human deaths following exposure to foxes, raccoons, skunks, and other wild mammals are very rare, and bites from rodents are not known to transmit rabies.
Contraction of rabies through inhalation of virus-containing aerosols, consumption of raw meat or milk of infected animals, or through organ transplantation is extremely rare.
Human-to-human transmission through bites or saliva is theoretically possible but has never been confirmed.
The incubation period for rabies is typically 2–3 months but may vary from one week to one year, depending on factors such as the location of virus entry and the viral load. Initial symptoms of rabies include generic signs like fever, pain and unusual or unexplained tingling, pricking, or burning sensations at the wound site. As the virus moves to the central nervous system, progressive and fatal inflammation of the brain and spinal cord develops. Clinical rabies in people can be managed but very rarely cured, and not without severe neurological deficits.
There are two forms of rabies:
Currently there are no WHO-approved diagnostic tools for detecting rabies infection before the onset of clinical disease.
Clinical diagnosis of rabies is difficult without a reliable history of contact with a rabid animal or specific symptoms of hydrophobia or aerophobia.
Accurate risk assessment is crucial for deciding on PEP administration.
Once symptoms emerge, and death is inevitable, offering comprehensive and compassionate palliative care is recommended.
Postmortem confirmation of rabies infection is done by various diagnostic techniques that detect whole viruses, viral antigens, or nucleic acids in infected tissues (brain, skin or saliva) (Laboratory techniques in rabies Vol. 1 and Vol. 2).
Where possible, the biting animal should be tested.
Vaccinating dogs, including puppies, through mass dog vaccination programs is the most cost-effective strategy for preventing rabies in people because it stops the transmission at its source.
Culling free roaming dogs is not effective in controlling rabies.
Public education for both children and adults on dog behaviour and bite prevention, what to do if bitten or scratched by a potentially rabid animal, and responsible pet ownership are essential extensions of rabies vaccination programmes.
Effective vaccines are available to immunize people both before and after potential exposures. As listed under the WHO – Prequalification of Medical Products, as of 2024, there are only 3 WHO pre-qualified human rabies vaccines available globally: RABIVAX-S by Serum Institute of India Pvt. Ltd., VaxiRab N by Zydus Lifesciences Limited, and VERORAB by Sanofi Pasteur.
Pre-exposure prophylaxis (PrEP) is recommended for people in high-risk occupations (laboratory workers handling live rabies and related viruses) and people whose professional or personal activities might lead to direct contact with infected animals (animal disease control staff and wildlife rangers).
PrEP might be indicated before recreation or travel in some areas, and for people living in remote, highly rabies-endemic areas with limited local access to rabies biologicals.
Note that PrEP does not replace the need for PEP. Any person exposed to a suspected rabid animal should still seek post exposure care.
Post-exposure prophylaxis (PEP) is the emergency response to a rabies exposure. This prevents the virus from entering the central nervous system. A well performed wound risk assessment and PEP protocol consists of:
Depending on the severity of exposure, administration of a full PEP course is recommended as follows:
NB: Category II and III exposures require human rabies vaccination.
WHO recommends that all human rabies vaccines comply with WHO standards.
Deployment of poor-quality rabies vaccines has led to public health failures in several countries.
As detailed in the guidance on PEP administration, WHO recommends moving from intramuscular (IM) to intradermal (ID) administration of human rabies vaccines.
Intradermal administration reduces the amount of necessary vaccine and number of doses, therefore reducing costs by 60–80%, without compromising safety or efficacy.
Fewer doses also promote patient compliance with the recommended regimen.
Rabies is included in WHO’s 2021–2030 Roadmap for the global control of NTDs, which sets regional, progressive targets for the global strategic plan to end human deaths from dog-mediated rabies by 2030 (see also: Zero by 30). This entails:
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