How is rabies transmitted from one dog to another? - briefly
Rabies is primarily transmitted through the bite of an infected animal, as the virus is present in the saliva of the infected dog. The virus can also be transmitted if the saliva of an infected dog comes into contact with an open wound or mucous membranes of another dog.
How is rabies transmitted from one dog to another? - in detail
Rabies, a viral disease caused by the Lyssavirus genus, is primarily transmitted through the bite of an infected animal. In dogs, this transmission process occurs in several detailed steps:
Firstly, rabies virus (RABV) replicates within the salivary glands of an infected dog, leading to a high concentration of the virus in its saliva. This is why bites are the most common mode of transmission. When an uninfected dog is bitten by a rabid dog, the virus is introduced into the new host's body through the broken skin and muscle tissue.
Once inside the new host, the RABV begins to replicate in the local muscles at the site of the bite before spreading to the central nervous system (CNS). The virus travels along the peripheral nerves towards the CNS, a journey that can take anywhere from 3 to 12 weeks, depending on the distance between the bite site and the brain. During this incubation period, the dog appears healthy and shows no clinical signs of infection.
Upon reaching the CNS, the RABV replicates rapidly in neurons, causing inflammation and damage to the brain and spinal cord. This neurological phase is characterized by a change in the dog's behavior, including increased aggression, disorientation, restlessness, and excessive salivation (hydrophobia). As the disease progresses, the virus continues to spread throughout the CNS and eventually makes its way back to the salivary glands.
At this stage, the infected dog becomes highly contagious, shedding large amounts of RABV in its saliva. Any contact with the saliva of a rabid dog, whether through a bite or even a scratch that breaks the skin, can transmit the virus to another dog. Additionally, the virus can be present in other bodily fluids, such as tears and urine, although transmission through these routes is less common.
It is important to note that rabies is almost always fatal once clinical signs appear. However, prompt veterinary intervention and post-exposure prophylaxis (PEP) can prevent the onset of symptoms in dogs that have been exposed to the virus but not yet developed clinical signs. Vaccination remains the most effective means of preventing rabies transmission among dogs and other animals.
In conclusion, the transmission of rabies from one dog to another occurs through a complex process involving viral replication, neurological spread, and behavioral changes. Understanding this process is crucial for implementing effective preventive measures and controlling the spread of this deadly disease.