May 12, 2000 -- Call it the paradox of rabies. It is 100% fatal -- but at the same time, 100% preventable. The key is prompt and effective treatment.
That paradox was certainly on the mind of Karen Slote, of Newton, Mass., last month, after her 10-year-old daughter was attacked by a rabid fox. The small, dog-sized creature snuck up on Nina and a friend as they were walking bicycles up the street.
"He got her in the back of the calf," Slote says. "He was biting and scratching at her legs. She fell down. I ran out -- I didn't have a plan -- and luckily the fox just stopped and backed off a little."
The Slote house was actually the third stop for the crazed fox. Earlier that morning it attacked a baby and a toddler and finished up the day by dueling with an elderly man who beat it off with a squeegee. That's when Newton Police took over and shot it dead.
Disturbing as the rampage was, experts suggest it would be better if all exposures to rabid animals were as obvious. They're not. "In the last couple of decades, most of those who have died of rabies in the United States were infected with bat-strain rabies," says Michael McGuill, DVM, public health veterinarian with the Massachusetts Department of Public Health. "Only one had a known bite."
McGuill says it may be that bat bites are so insignificant that they go unnoticed.
Not that people are dropping dead all over the place from rabies. In its latest report on the disease, the CDC notes that just 22 humans developed rabies since 1990, and 20 of those were from bats. Public health investigators only know that because rabies viruses can be genetically traced to the animal of origin. In other words, different species of mammals harbor different strains of rabies. The rampaging fox in Newton got rabies from a rabid raccoon, McGuill says, but there is also a "fox rabies" virus.
Fortunately, one vaccination type covers all strains of rabies. It's called human diploid cell vaccine (HDCV) and it's used in conjunction with rabies immunoglobulin (RIG). The former provides what's known as "active" immunity -- but it takes around a month to kick in. To cover that time period, RIG is injected right after the bite. It provides almost immediate protection from the virus -- which slowly travels up nerves to the spinal cord and brain. Together they are known as post-exposure prophylaxis (PEP).
The treatment is easy -- and relatively painless. "It's a series of seven injections over a month's time," says Mille Vitale, RN, rabies nurse for Pinellas County, Fla. "You will have five visits to the doctor, on days zero, three, seven, 14, and 28 -- and that schedule has to be kept. You will be getting the vaccinations in the upper arm, on alternate arms."
"Most people still think you get them in the stomach -- and you absolutely don't," says Slote. But you can get the RIG injected in unusual places -- depending on where the bites are. "Nina had three places where the fox bit or scratched her and she had to have some RIG injected into each of those spots."
The HDCV/RIG regimen is a huge advance from what might be called the Dark Ages of rabies treatment, Vitale says, when the vaccinations were so numerous they had to be given in places such as the abdomen -- and even then, didn't always work.
"It's much easier to treat patients and much easier to recommend treatment," says Alfred DeMaria, MD, director of communicable disease control at the Massachusetts Department of Public Health. "Now the risk of treatment is virtually nil."
Which is not to suggest anyone who comes in contact with a rabid animal necessarily needs treatment. It really depends on how "contact" is defined. Public health experts say the greatest danger lies in getting the saliva of a rabid animal, or its brain or nervous system tissue, into an open cut. That could happen through a bite, of course, or indirectly.
That was the case with Roland Vaillancourt, a paramedic from Greenville, N.H. One day eight years ago he noticed an odd sight: a raccoon wandering around a neighborhood in daylight. "So something was wrong," he says. "It was acting very unusual -- slow [breathing], unsteady gait. We just decided to put it down at that point."
He used a bow and arrow, and accidentally cut himself on the arrowhead, which was tainted with the raccoon's nervous system tissue. But Vaillancourt underwent PEP and didn't have any problem.
Another method of indirect exposure: getting saliva or nervous system tissue splashed onto a mucous membrane, such as the eye. But experts say it's important to note that blood, urine, and droppings from rabid animals cannot transmit the virus.
Cats and dogs were once important rabies transmitters -- but no more. Now, raccoons are king up and down the East Coast. In fact, three years ago, Canada mounted an intensive effort to keep rabid raccoons from spreading into Ontario. Planes flew over the border, dropping thousands of oral rabies vaccine doses hidden inside food bars. It failed.
Ontario's current efforts to control the disease's spread include establishment of a five-kilometer "kill" zone at two entry points -- where every raccoon seen is exterminated. There is also an outer zone in which raccoons are trapped and vaccinated. And beginning in June, a shower of vaccinated bait bars will be airdropped into the area.
A similar effort on Cape Cod, Mass., seems to have done the trick. DeMaria says raccoon rabies there have been virtually eliminated.
McGuill says rabies may rise and fall among animal populations -- in great part, because animals die from it -- but at this point it remains a problem. "There's no indication it's going away."
That said, DeMaria has some recommendations to avoid an exposure: First, avoid any animal you don't know -- especially one which is behaving unusually. That could mean an overly aggressive creature, but also one that is too docile. A raccoon or fox shouldn't be seeking human contact -- they're normally afraid.
"Second, reduce the environment and habitat for potentially rabid animals by reducing food and nesting sources," DeMaria says. "Third, immunize your pets -- cats and dogs."
And if you are bitten, thoroughly wash the wound with soap and water -- this is an important step, since the virus may be broken down by soap. And always see a doctor.
- Since 1990, only 22 people have died from rabies, usually as the result of an unnoticed bite from a bat.
- A person contracts rabies by coming into contact with the saliva or brain tissue of a rabid animal, but can prevent the disease with a series of seven shots over a month's time following exposure.
- If you are bitten by an animal, thoroughly wash the wound with soap and water, then see a physician.