DEAR DR. DONOHUE: I have my dogs vaccinated for rabies, but I wonder how necessary this is. I have never heard of a case of rabies. From what animals can people get it? Is it treatable and curable? What actually is it? – O.R.

ANSWER: In the United States and Canada, very few rabies cases are seen in a year, and almost none from domestic animals like cats and dogs because of our policies requiring pet vaccinations. Around the world, however, there are about 55,000 rabies cases annually, and just about 100 percent die from the infection if they are not treated before the signs of rabies develop.

Raccoons, skunks, foxes, wolves and coyotes are the principal carriers of the rabies virus. The No. 1 rabies spreader is bats.

The virus in saliva, transferred from a bite, causes no symptoms for one to three months. At that point, the bitten person comes down with a headache, fever, muscle aches, fatigue and loss of appetite – all common to many other illnesses. One to four days later, the person becomes confused and hallucinates. Muscles go into violent spasms. Saliva and tear production increase markedly. The thought of taking a drink sets off a painful series of contractions of the swallowing muscles. That’s the famous hydrophobia – fear of water – rabies sign. Quickly, the person then slips into a coma, and death is inevitable. Recently, a young woman in Wisconsin did survive rabies.

If a person is immunized soon after being bitten by a rabid animal or bat, the illness does not develop. That is why, if bitten, it is so important to observe domestic animals whose rabies vaccination is doubtful and to send the brain of the wild animal to the state lab when it is possible to do so. Today, only five shots, given over one month, can abort rabies. The shots are not painful.

DEAR DR. DONOHUE: I am 82 and have osteoporosis really bad. I suddenly developed terrific back pain. My doctor got an X-ray, which showed a compression fracture of one backbone. The doctor sent me to an orthopedic doctor, who wants to perform vertebroplasty. Will you explain both the procedure and compression fracture. I am in the dark on both. – W.C.

ANSWER: Osteoporotic bones are quite fragile. Osteoporosis often involves the backbones – the vertebrae. Those bones can become so weak that they can no longer support body weight, which crushes one or more backbones. That’s a compression fracture. Such fractures are quite painful.

During a vertebroplasty, the doctor places two needles in the collapsed backbone. Through the needles a cementlike substance is injected into the bone. The person must remain lying down for two hours after the injection to give the material a chance to harden. After injection and hardening, the backbone regains most of its former height, and often, pain goes away. It’s not successful all the time, but it’s successful enough of the time that when a doctor suggests it, it’s worth following the suggestion.

A similar procedure is called kyphoplasty. Here, the doctor introduces a balloon into the backbone and expands the balloon to create a hollow to receive the cement material. The result is similar to a vertebroplasty.

Which is better? It depends on the fracture, the patient’s general health and the doctor’s training.

DEAR DR. DONOHUE: Would heavy lifting cause a kidney to dislodge into the pelvis? The lifting was followed by severe pain down the leg. – Curious

ANSWER: Heavy lifting is not likely to dislodge a kidney.

It might cause a disk between two backbones to bulge. A bulging disk can press on adjacent nerves and cause pain that runs down a leg.

Dr. Donohue regrets that he is unable to answer individual letters, but he will incorporate them in his column whenever possible. Readers may write him or request an order form of available health newsletters at P.O. Box 536475, Orlando, FL 32853-6475. Readers may also order health newsletters from www.rbmamall.com.

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