Understanding Rabies: A Deadly Zoonotic Disease
Rabies is a viral zoonotic disease that poses a significant public health threat worldwide. Despite being preventable, it continues to cause approximately 59,000 deaths annually1. Here’s a detailed look at rabies, its impact, and key facts to help raise awareness and promote prevention.
Key Facts About Rabies
Global Impact: Rabies causes around 59,000 deaths per year, with 99% of these deaths resulting from dog bites1.
Geographical Distribution:
Africa and Asia: These continents account for 95% of human rabies deaths, with Africa seeing around 24,000 deaths and Asia around 20,000 deaths annually1.
India: India alone reports approximately 20,000 rabies deaths each year1.
High-Risk Groups:
Children: Nearly 40% of rabies deaths occur in children under the age of 15. They are at higher risk due to their likelihood of playing with stray dogs and often getting bitten on the face, which shortens the incubation period1.
Rabies in the UK: Since 2000, four people in the UK have died from rabies, all contracting the infection from dog bites while on holiday2.
High-Risk Regions in Europe: Eastern Europe, particularly Ukraine, Belarus, and Russia, shows higher rabies risk. Additionally, Turkey, Greece, Crete, Cyprus, Tunisia, Morocco, southern Italy, and Spain are also concerning areas1.
The map below shows the recorded rabies cases Europe in dogs and cats alone since 2010:
Transmission and Symptoms
Rabies is transmitted through the saliva of an infected animal, typically via bites or scratches. It can also enter the body through open wounds or mucous membranes (e.g., eyes, mouth)1.
Reservoir Hosts: While all mammals are susceptible to rabies, only a few species act as reservoirs, maintaining and transmitting the virus. These include raccoons, foxes, and dogs1.
Incubation Period: The incubation period varies depending on the distance from the bite site to the brain and the viral load. Bites on the foot can take weeks to months to show symptoms, while bites near the face result in a shorter incubation period1.
Rabies is a viral disease that primarily affects the central nervous system (CNS). Here’s a step-by-step explanation of how the rabies virus works once it enters the body:
Entry Point: The rabies virus typically enters the body through the saliva of an infected animal, usually via a bite or scratch. It can also enter through open wounds or mucous membranes (e.g., eyes, mouth)1.
Initial Infection: Once inside the body, the virus attaches to nerve cells at the site of the bite or scratch. It specifically targets the peripheral nervous system (PNS), which includes all the nerves outside the brain and spinal cord1.
Travel to the CNS: The virus travels along the peripheral nerves towards the spinal cord and brain. This movement is relatively slow, which is why the incubation period can vary from weeks to months, depending on the location of the bite and the viral load12.
Replication in the CNS: Upon reaching the spinal cord and brain, the rabies virus begins to replicate rapidly. It infects nerve cells, causing inflammation and damage. This is when neurological symptoms start to appear13.
Spread to Other Tissues: After replicating in the brain, the virus travels along other nerves to various tissues, including the salivary glands. This is why the saliva of an infected animal is highly contagious4.
This video provides a comprehensive overview of rabies in dogs and other animals, highlighting clinical signs such as howling, aggression, difficulty swallowing, restlessness, and incoordination. You can watch it here1.
Fatality: Once symptoms develop, rabies is always fatal. Symptoms progress rapidly, leading to coma and death within two weeks1.
Prevention and Control
Vaccination: Rabies is preventable through vaccination. Mass dog vaccination and prompt post-exposure prophylaxis (PEP) are crucial in preventing human rabies deaths1.
PEP: Post-exposure prophylaxis involves thorough wound washing, administration of rabies vaccine, and, when necessary, rabies immunoglobulins1.
Public Awareness: Educating communities about bite prevention and the importance of seeking immediate medical care after potential exposure is vital1.
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