- Hello Jeff - As you know, I've been very concerned about
rabies for quite some time. And with good reason...
-
- From ProMED-mail
-
- By Frank D Roylance Baltimore Sun
- 12-16-5
-
- A woman heard about the rabid raccoon in her Dickeyville
neighborhood soon after the animal attacked and bit a friend, on 2 Dec
2005. Even so, she was surprised when, a few hours later, a raccoon appeared
out of nowhere as she walked her mixed spaniel. The crazed animal charged
her and clamped its jaws on the leg of her corduroy pants.
-
- The woman, 61, didn't realize she was at the epicenter
of a surge in animal rabies cases that would spur Baltimore's health commissioner
to issue a citywide public health alert yesterday, 15 Dec 2005. Nor could
she know how frustrating it would be to get all of her rabies shots with
a key serum in short supply.
-
- She only knew at the time that there was an angry raccoon
attached to her slacks. "I tried kicking at it, screaming and waving
my arm," she recalled. "My dear dog ignored the whole thing."
Unfortunately, her kicks threw her off balance and she wound up on her
knees, face to face with her attacker. "I've got the tail in my right
hand, and the front left leg in my left hand, and the back of my left fist
under its jaw. And I have it pinned on the ground," she said.
-
- Neighbors heard her shouts and called 911. One of them
came to her aid. "He walks up and asks if there is anything he could
do for me," she said. She replied, "Either hog-tie it or bash
its brains in, please!" He chose the second option, clobbering the
raccoon's head with a handy rock.
-
- The animal tested positive for rabies, the 10th raccoon
and 18th animal found with rabies in the city in 2005. In 2004, there were
only 2, according to the city Health Department.
-
- Animal bites, too, are up sharply in the city, according
to health officials. Most involve dogs and cats, which are supposed to
be vaccinated against rabies. But bites by raccoons and bats -- both well-known
carriers of rabies -- are also up, from 68 in 2004 to 100 in 2005. Some
of the increase might be the result of "increased vigilance,"
said city health commissioner Dr Joshua M Sharfstein. But the figures "likely
also indicate a growing problem." In the health alert issued yesterday,
he said, "Rabies is a fatal disease, and city residents need to be
aware of this risk. Stay away from suspect animals, and seek treatment
quickly if possibly exposed."
-
- State health authorities said they've seen no major changes
in the overall incidence of animal rabies. "Whether something is changing
in the city, I don't know," said John P Krick, director of Maryland's
office of epidemiology and disease control. "We are not staffed to
the point where we can analyze in depth the rise in numbers."
-
- The increase in animal rabies and bite cases in Baltimore
has raised the demand for human rabies shots. They consist of rabies vaccine,
plus a scarce and costly antibody serum, human rabies immune globulin (HRIG).
-
- In 2005, 68 patients have sought and received rabies
shots in the city, up from 43 in 2004. The rising demand and tight supplies
can sometimes delay treatment, which the patient discovered when she went
to the city health department last week for her shots. Officials there
told her they had run out of HRIG, and her antibody treatment was delayed
nearly to the point where it would have been ineffective [see discussion
below - Mod.LL].
-
- The current eastern US epizootic of raccoon rabies (the
animal equivalent of a human epidemic) is "one of the biggest wildlife
rabies outbreaks on record, ever," said Dr Cathleen A Hanlon, veterinary
medical officer in the Rabies Section at CDC in Atlanta.
-
- It began in Florida in the 1950s and spread north, aided
by suburban sprawl, access to garbage, and a human tolerance for animals.
It reached the Middle Atlantic states in the 1970s and has spread explosively
from there. Raccoons are now the most common source of rabies from Ohio
and the Appalachian ridge to the Atlantic, and from Ontario to the Gulf
of Mexico. Their knack for survival in the city and suburbs puts them in
direct contact with dense human populations and their pets.
-
- Laboratory tests have confirmed 300 to 400 cases of animal
rabies in Maryland annually in recent years. About 2/3 were raccoons, followed
distantly by bats, foxes, cats, and skunks. The numbers rise and fall in
cycles. But the statewide trend in recent years has actually been down,
from 396 in 2002 to 334 in 2004. The total through 15 Oct of 2005 was 319.
-
- An exception is Baltimore City. Although its counts are
small compared with suburban counties, they're up sharply in 2005, prompting
yesterday's health alert.
-
- Rabies is a viral illness that attacks the brain. It
is transmitted from wild animals to unvaccinated pets and people through
the saliva of the infected animal. Symptoms, which can appear days or years
after exposure, include pain at the bite site, fever, chills, muscle aches
and irritability, leading to confusion, agitation, seizures, coma, and
death.
-
- Hanlon estimated that 30 000 to 50 000 people receive
rabies shots each year. CDC guidelines call for 5 doses of rabies vaccine.
They should start as soon as possible after exposure, and then 3, 7, 14,
and 28 days after the 1st shot. The vaccine, injected into the shoulder
muscle, stimulates the body to produce its own antibodies to fight and
destroy the rabies virus. But development of those antibodies takes about
a week. So the guidelines also call for a single dose of HRIG, ideally
with the 1st vaccine shot. HRIG antibodies are extracted from donated human
blood.
-
- HRIG is injected [partly - Mod.LL] into and around the
bite, if there is one, and the rest into a muscle. Its job is to provide
immediate -- though temporary -- protection against the virus while the
patient's immune system, responding to the vaccine, builds its own antibodies.
-
- But to do the patient any good, the HRIG must be given
within 7 days of the 1st vaccine shot. After that, the body is presumed
to have produced its own antibodies. The patient received her 1st vaccine
shot 7 Dec 2005 at the city Health Department's Field Services Unit. But
the department had run out of HRIG. Although officials told Davis they
expected to be resupplied in time for her 2nd rabies shot, they weren't.
And it was uncertain whether they would get more in time for her 3rd. So
she was advised to seek treatment at Sinai Hospital.
-
- She went to Sinai's emergency room and -- after 10 hours
in the waiting room -- she finally received both her 3rd rabies vaccine
shot and her HRIG injection. By then, 12 days had passed since the raccoon
attack. And the window for the HRIG to provide her any protection had all
but closed.
-
- "That's not ideal. I'm surprised," Hanlon said
of Davis' experience. Sharfstein, the city's health commissioner, said
such delays are "a very common thing in rabies because there's a pretty
scarce supply" of HRIG.
-
- "I've been in [hospital] emergency rooms that don't
have any when a patient is there," he said. But he agreed that the
delay in Davis' case was too long. In any event, he said that the patient
- who was not actually bitten by the raccoon - is at "extraordinarily
low risk" for getting rabies.
-
- The rabies vaccine is readily available, Hanlon said,
although the 3 manufacturers that once shared the USA market have dwindled
to one in recent years - Chiron Corp. But HRIG supply problems are national,
she said. The only commercial manufacturers are Germany's Bayer and France's
Aventis Pasteur. "It's kind of an orphan biologic, not a big money-maker
and sort of a limited supply," she said.
-
- Because it's derived from donated human blood, production
is limited, so the product is very expensive -- $1000 to $1800 per dose.
And it has a shelf life of just 2 years. As a result, health care providers
can't afford to stock much HRIG, and they frequently have to ask public
health officials to help them find more.
-
- Despite Davis' close contact with the raccoon, and despite
the delay in administering the HRIG antibodies, Hanlon said, "the
fact that she wasn't bitten ... probably provided a sufficient margin of
safety where she's not at significant risk."
-
- http://www.baltimoresun.com/news/nationworld/bal-te.rabies15dec15,1,4937
-
- ProMED-mail promed@promedmail.org
-
- It would appear that rabies incidents are up in this
area of Maryland. It may be due to a real rise in rabies, or it may be
due to more awareness, resulting in better reporting.
-
- Clearly, with this type of rise, regardless of the reason,
vaccination of domestic animals (especially cats and dogs) becomes a critical
issue in decreasing exposure to people. When unvaccined pets come into
contact with a rabid animal such as a raccoon, they are exposed to the
virus, and put the pet owner at risk.
-
- The shortage of supplies for post-exposure prophylaxis
is concerning. - Mod.TG
-
- Natural rabies is transmitted only when the virus in
saliva is introduced into a bite wound, open cut, or onto mucous membranes.
Any penetration of skin by teeth is considered a bite exposure. Bites by
some animals, especially bats, can inflict quite minor injury and may go
undetected in a sleeping person.
-
- Based on the comments, it appears that the rabid raccoon's
dentition did not penetrate the patient's skin and, if so, one might argue
that no prophylaxis was needed. It is possible, however, that saliva did
contaminate an open cut or abrasion during the scuffle. Aerosolized rabies
virus, in large quantities, has transmitted rabies, with cases occurring
from exposure in a laboratory and bat-infested cave. Organ transplants
have also rarely transmitted the infection.
-
- Several aspects of post-exposure prophylaxis also need
mentioning.
-
- 1) Immediate and extensive washing of all bite wounds
and scratches with soap and water and a virucidal agent such as povidine-iodine
irrigation are important in preventing rabies. Indeed, in animals, this
alone reduces the likelihood of rabies markedly (1,2).
-
- 2) Small rodents (such as squirrels, hamsters, guinea
pigs, chipmunks, rats, and mice) as well as lagomorphs (rabbits and hares)
are almost never found to be infected with rabies and have not been known
to transmit rabies to humans. The woodchuck, quite a large rodent, accounts
for most rodent rabies in endemic areas of rabies.
-
- 3) Much of the rabies prophylaxis is given related to
dog and cat bites. This can be minimized by immunizing one's pets against
this infection.
-
- 4) In my experience working at a number of hospitals
in rabies-endemic areas, HRIG has always been located in town even if it
is not in stock at the institution that requires it. This may well have
been accomplished in the scenario described.
-
- 1. Kaplan MM, Cohen D, Koprowski H, et al. Studies on
the local treatment of wounds for the prevention of rabies. Bull World
Health Organ 1962; 26: 765-75. 2. Dean DJ, Baer GM, Thompson WR. Studies
on the local treatment of rabies-infected wounds. Bull World Health Organ
1963; 28: 477-86.
-
- Much of this information is derived from: CDC. Human
rabies prevention - United States, 1999. Recommendations of the Advisory
Committee on Immunization Practices (ACIP). MMWR 1999; 48 (RR-1):1-21.
- Mod.LL]
-
- .....................tg/ll/pg/sh
-
- Patricia A. Doyle, DVM, PhD- Bus Admin,
- Tropical Agricultural Economics
-
- Please visit my "Emerging Diseases" message
board at: http://www.clickitnews.com/ubbthreads/postlist.php?
- Cat=&Board=emergingdiseases
-
- Zhan le Devlesa tai sastimasa
- Go with God and in Good Health
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