What you need to know about rabies

Rabies is a virus that is usually spread by the bite or scratch of an animal. By the time the symptoms appear, it is generally too late to save the patient.

However, a person who may have been exposed to rabies can usually be treated effectively if they seek help at once.

In the United States, between 1 and 3 people contract rabies each year. From 2008 to 2017, the U.S. saw 23 human cases, eight of which were contracted outside the country. Advances in medicine, awareness, and vaccination programs have reduced the incidence of rabies since the 1970s.

However, globally, it remains a problem, and tens of thousands of deaths result from rabies each year, mostly in rural areas of Southeast Asia and Africa. Over 95 percent of infections are caused by dogs.

Rabies is a viral infection that mainly spreads through a bite from an infected animal. It is an RNA virus of the rhabdovirus family.

Without early treatment, it is usually fatal.

The virus can affect the body in one of two ways:

It enters the peripheral nervous system (PNS) directly and migrates to the brain.

It replicates within muscle tissue, where it is safe from the host’s immune system. From here, it enters the nervous system through the neuromuscular junctions.

Once inside the nervous system, the virus produces acute inflammation of the brain. Coma and death soon follow.

Rabies is most common in countries where stray dogs are present in large numbers, especially in Asia and Africa.

It is passed on through saliva. Rabies can develop if a person receives a bite from an infected animal, or if saliva from an infected animal gets into an open wound or through a mucous membrane, such as the eyes or mouth. It cannot pass through unbroken skin.

In the U.S., raccoons, coyotes, bats, skunks, and foxes are the animals most likely to spread the virus. Bats carrying rabies have been found in all 48 states that border with each other.

Any mammal can harbor and transmit the virus, but smaller mammals, such as rodents, rarely become infected or transmit rabies. Rabbits are unlikely to spread rabies.

If a person is bitten or scratched by an animal that may have rabies, or if the animal licks an open wound, the individual should immediately wash any bites and scratches for 15 minutes with soapy water, povidone iodine, or detergent. This might minimize the number of viral particles.

A series of rabies vaccines: These will be injected into the arm over the next 2 to 4 weeks. These will train the body to fight the virus whenever it finds it.

It is not usually possible to find out whether the animal has rabies or not. It is safest to assume the worst and begin the course of shots.

A small number of people have survived rabies, but most cases are fatal once the symptoms develop. There is no effective treatment at this stage.

A person with symptoms should be made as comfortable as possible. They may need breathing assistance.