Rabies

Rabies is a viral disease that causes inflammation of the brain in humans and other mammals. Early symptoms can include fever and abnormal sensations at the site of exposure, which are followed by nausea, vomiting, violent movements, uncontrolled excitement, fear of water, inability to move parts of the body, confusion, and loss of consciousness. Once symptoms appear, the result is virtually always death. The time period between contracting the infection and the start of symptoms is usually one to three months but can vary from less than one week to more than one year. The time depends on the distance the virus must travel along peripheral nerves to reach the central nervous system. Rabies is caused by lyssaviruses, including the rabies virus and Australian bat lyssavirus. It is spread when an infected animal bites or scratches a human or other animals. Even in the absence of a bite or a scratch, saliva from an infected animal coming into contact with the eyes, mouth, or nose can transmit rabies. Rabies can also be transmitted through tears and nervous tissues. Globally, dogs are the most common animal involved. In countries where dogs commonly have the disease, more than 99% of rabies cases in humans are the direct result of dog bites. In the Americas, bat bites are the most common source in humans, and less than 5% of cases are from dogs. Rodents are very rarely infected with rabies. The disease can be diagnosed only after the start of symptoms, but prompt preventative treatment is recommended for anyone who has had contact with a rabid animal. Animal control and vaccination programs have decreased the risk of rabies from dogs in a number of regions of the world. Immunizing people before they are exposed is recommended for those at high risk, including those...