How soon do humans show signs of rabies

Rabies

Jason Howland:The most dangerous threat of rabies in the U.S. is flying overhead.

Gregory Poland, M.D., Vaccine Research Group Mayo Clinic:"It used to be thought, well, it's a rabid dog. But the more common way of getting rabies is from the silver-haired bat."

Jason Howland:The deadly virus is transmitted from the saliva of infected animals to humans, usually through a bite.

Dr. Poland:" The bat doesn't always bite. Sometimes the saliva will drool onto you, and you could have a minor open cut. Or sometimes a bat will lick on the skin and, again, transmit the virus that way."

Jason Howland:Dr. Poland says that's why if you wake up and find a bat in the room, you should get the rabies vaccine.

Dr. Poland:"People think, 'Well, the bat's in the house. We woke up with it, doesn't look like it bit anybody.' Doesn't matter. Rabies is such a severe disease with no cure, no treatment for it, that the safer thing to do is to give rabies vaccine."

Jason Howland:That includes an immune globulin and multidose rabies series which is not cheap. A typical series of rabies vaccines cost anywhere from three to seven thousand dollars.

For the Mayo Clinic News Network, I'm Jason Howland.

Signs of a Rabid Cat and What to Do If Your Pet Is Exposed

There are usually three distinctive stages with rabies in cats. The first one is called theprodromal stage. In this stage, a rabid cat will usually exhibit changes in behavior that aren't typical for their personality: A shy cat can become outgoing, an outgoing cat can become shy, and so on.

The second is called thefurious stage the most dangerous phase in a rabid cat. In this stage, a rabid cat may become nervous and vicious. They may also excessively cry out and experience seizures and a loss of appetite. At this point, the virus is attacking the nervous system and prevents them from swallowing, leading to the classic sign of excessive drooling or foaming at the mouth.

The third is theparalytic stage, in which a rabid cat will go into a coma, be unable to breathe, and unfortunately, most often pass. This stage usually occurs about seven days after signs have started, with death often occurring around day 10.

The Path of the Rabies Virus

The Virus Travels through the Body

From numerous studies conducted on rabid dogs, cats, and ferrets, we know that when the rabies virus isintroduced into a muscle through a bite from another animal, it travels from the site of the bite to the brain by moving within nerves. The animal does not appear ill during this time.

The time between the bite and the appearance of symptoms is called the incubation period and it may last for weeks to months. A bite by the animal during the incubation period does not carry a risk of rabies because the virus has not yet made it to the saliva.

The Virus Reaches the Brain

Late in the disease, after the virus has reached the brain and multiplied there to cause an inflammation of the brain, it moves from the brain to the salivary glands and saliva.

Also at this time, after the virus has multiplied in the brain, almost all animals begin to show the first signs of rabies. Most of these signs are obvious to even an untrained observer, but within a short period of time, usually within 3 to 5 days, the virus has caused enough damage to the brain that the animal begins to show unmistakable signs of rabies.

Extensive studies on dogs, cats, and ferrets show that the rabies virus can be excreted in the saliva of infected animals several days before illness is apparent. Such extensive studies have not been done for wildlife species, but it is known that wildlife species do excrete rabies virus in their saliva before the onset of signs of illness. The excretion of virus may be intermittent, and the relative amount of excreted virus may vary greatly over time, before and after the onset of clinical signs.

The reason there is so much variation in the time between exposure and the onset of the disease is that many factors come into play, including the site of the exposure, the type of rabies virus, and any immunity in the animal or person exposed.