Rabies

Etymology:
– The name rabies is derived from the Latin rabies, meaning madness.
– The Greeks derived the word lyssa from lud or violent.
– This root is used in the genus name of the rabies virus, Lyssavirus.

Signs and symptoms:
– Animals with dumb rabies appear depressed, lethargic, and uncoordinated.
– The incubation period in humans is typically one to three months.
– The period may vary from four days to over six years, depending on factors.
– Initial symptoms are often nonspecific like fever and headache.
– As rabies progresses, symptoms can include paralysis, anxiety, confusion, and hallucinations.

Transmission:
Rabies is caused by lyssaviruses, including the rabies virus and Australian bat lyssavirus.
– It spreads through infected animal bites or scratches.
– Saliva from infected animals can also transmit rabies.
– Globally, dogs are the most common animal involved in spreading rabies.
– In the Americas, bat bites are the most common source of rabies infections in humans.

Prevention:
– Animal control and vaccination programs have reduced rabies risk in many regions.
– Pre-exposure immunization is recommended for high-risk individuals.
– Post-exposure treatment with rabies vaccine and immunoglobulin can prevent the disease.
– Washing bites and scratches with soap and water may reduce viral transmission.
– Only fourteen documented cases of surviving rabies after symptoms have been shown.

Epidemiology:
Rabies causes about 59,000 deaths worldwide annually.
– Approximately 40% of deaths are in children under 15 years old.
– Over 95% of human rabies deaths occur in Africa and Asia.
Rabies is present in more than 150 countries across all continents except Antarctica.
– More than 3 billion people live in regions where rabies occurs.

Rabies (Wikipedia)

Rabies is a viral disease that causes encephalitis in humans and other mammals. It was historically referred to as hydrophobia ("fear of water") due to the symptom of panic when presented with liquids to drink. Early symptoms can include fever and abnormal sensations at the site of exposure. These symptoms are followed by one or more of the following symptoms: nausea, vomiting, violent movements, uncontrolled excitement, fear of water, an inability to move parts of the body, confusion, and loss of consciousness. Once symptoms appear, the result is virtually always death, regardless of treatment. The time period between contracting the disease 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
A man suffering from rabies tied to a hospital bed.
A man with rabies, 1958
SpecialtyInfectious disease
SymptomsFever, extreme aversion to water, confusion, excessive salivary secretion, hallucinations, disrupted sleep, paralysis, coma, hyperactivity, headache, nausea, vomiting, anxiety
CausesRabies virus, Australian bat lyssavirus
PreventionRabies vaccine, animal control, rabies immunoglobulin
TreatmentSupportive care
MedicationIncurable
Prognosis>99% fatal after onset of symptoms
Deaths59,000 per year worldwide

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. Saliva from an infected animal can also transmit rabies if the saliva comes into contact with the eyes, mouth, or nose. Globally, dogs are the most common animal involved. In countries where dogs commonly have the disease, more than 99% of rabies cases are the direct result of dog bites. In the Americas, bat bites are the most common source of rabies infections 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.

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 who work with bats or who spend prolonged periods in areas of the world where rabies is common. In people who have been exposed to rabies, the rabies vaccine and sometimes rabies immunoglobulin are effective in preventing the disease if the person receives the treatment before the start of rabies symptoms. Washing bites and scratches for 15 minutes with soap and water, povidone-iodine, or detergent may reduce the number of viral particles and may be somewhat effective at preventing transmission. As of 2016, only fourteen people were documented to have survived a rabies infection after showing symptoms. However, research conducted in 2010 among a population of people in Peru with a self-reported history of one or more bites from vampire bats (commonly infected with rabies), found that out of 73 individuals reporting previous bat bites, seven people had rabies virus-neutralizing antibodies (rVNA). Since only one member of this group reported prior vaccination for rabies, the findings of the research suggest previously undocumented cases of infection and viral replication followed by an abortive infection. This could indicate that people may have an exposure to the virus without treatment and develop natural antibodies as a result.

Rabies causes about 59,000 deaths worldwide per year, about 40% of which are in children under the age of 15. More than 95% of human deaths from rabies occur in Africa and Asia. Rabies is present in more than 150 countries and on all continents but Antarctica. More than 3 billion people live in regions of the world where rabies occurs. A number of countries, including Australia and Japan, as well as much of Western Europe, do not have rabies among dogs. Many Pacific islands do not have rabies at all. It is classified as a neglected tropical disease.