Thursday, July 25, 2013

ENTANGLED LIVES

1942, South Deer Creek, near Roseburg, OR
My mother on the far left, then my Aunt Allie, next my Great-Aunt Florence and some neighbor.

I got caught a little short on blogging today, so I’m going to reblog with some editing and comments.  For five years I sweated out rabies in Portland, OR, as an animal control officer in the field and then research and education coordinator.  One of my most effective tools for motivating the college kids who sold dog licenses door-to-door -- which meant the dogs got rabies shots -- was a movie of little kids in south Chicago dying of rabies.  No cure then, no cure now.  But we had preventive vaccinations.  No one knew whether they would work for sure.

By Nancy Walsh, Staff Writer, MedPage Today
Reviewed by Robert Jasmer, MD; Associate Clinical Professor of Medicine, University of California, San Francisco

A third instance of rabies transmission following organ transplantation has occurred, with a patient dying 18 months after receiving a kidney from a deceased donor who was not known to be infected with the rabies virus, researchers reported.
The extended incubation period was an unusual clinical feature because in the two previous episodes of transmission, all unvaccinated recipients developed symptoms within 6 weeks and died, according to Matthew Kuehnert, MD, of the CDC in Atlanta, and colleagues.
Also distinctive was the fact that three other individuals who received organs from the same donor remained asymptomatic and only developed rabies antibodies after post-exposure prophylaxis, the investigators wrote in the July 24/31 Journal of the American Medical Association.
Those previous cases had suggested "a high infectivity rate and an incubation period of approximately 6 weeks in unvaccinated immunosuppressed recipients of solid organs from donors with rabies," according to the investigators.
However, in the present case, that pattern wasn't followed. The organ donor was an apparently healthy male who had returned from a fishing trip and developed symptoms of nausea, vomiting, and paresthesias, and then seizures, altered mental status, dysphagia for liquids, and hemodynamic instability.
The presumed diagnosis at the time of death was ciguatera -- a marine toxin found in certain reef fish -- poisoning.
Family members reported no known exposure to rabies, and examination of the cerebrospinal fluid found no evidence of infectious disease. . .
The recipient initially was diagnosed with sciatica when seen for hip pain radiating to the leg, but was subsequently hospitalized with symptoms including fever, diaphoresis, and abdominal pain in the region of the transplanted kidney.
Encephalopathy followed, along with hemodynamic instability, and death occurred 3 weeks after admission . . .
It turned out that the donor had a history of exposure to wildlife, including trapping raccoons in North Carolina, and had been bitten twice by the animals, which were not available for rabies testing.

Only one previous case of rabies contracted from a raccoon bite has been reported, but they are the most commonly infected animal in the U.S.
Testing of retained serum and central nervous system (CNS) samples from the donor revealed encephalitis, necrosis of neurons, and intracytoplasmic inclusions in the cortex suggestive of rabies, along with viral antigens and RNA.
Gene sequencing of tissues from both donor and recipient revealed a 99.9% match of the N gene, and phylogenetic analysis traced the source as a single county in North Carolina, "confirming organ transplantation as the route of transmission," the researchers reported.
None of the three asymptomatic patients developed rabies, which has raised questions "about mechanisms of rabies virus spread within a host, the cells and tissues in which the virus resides during lengthy incubation periods, and how the virus evades the immune system," the investigators noted.
They suggested that contributing factors could include different immunosuppressive regimens in those patients following their transplants, the type of organ, and quantity of virus present, although the precise reasons remain uncertain.
Viruses are the code of life, but they could be considered either alive or not alive.  Raccoons are definitely alive, unless you’re some kind of frontiersman who needs a hat.  When I was an animal control officer there was a big old boar raccoon in my beat who was a pet, but sometimes got the idea that the humans were the pets.  Or pests.  Then maybe he’d bite them.  I took repeated reports and cautioned them to quarantine and watch the beast for symptoms of rabies.  The vet had given him dog immunization but no one knows whether it works on raccoons.  None of the people who were bitten developed rabies.  
No dog that has been vaccinated has ever developed rabies.  The people who do rabies research work with dogs let them have access to sunshine because rabies virus is killed by sunlight.  So it’s mostly carried by nocturnal animals, but a cow that has been bitten by a rabid animal can carry it for three years without developing symptoms -- and what if the cow bit you in those years?  No one knows.
The world is so full of complex codes, some of them in molecules and some of them in behavior patterns engraved on neurons, that on the one hand it seems impossible to even grasp what’s going on, much less predict.   And then you discover that CSI resources can not only discover that a kidney donor was carrying rabies but also track it to the species and the very county of the state where it lived.  But the key was knowing that the donor hunted raccoons.  Should that be on every organ donor questionnaire now?  “Have you ever hunted a raccoon?”   The veterinarian cautioned we who worked directly with dogs not to give blood, because we had undoubtedly picked up some strange “bugs”.
Few animals are as appealing to humans as dogs, but raccoons certainly are.  In childhood my brothers and I were exploring an old barn and found a couple of half-grown raccoons who were pets, though no one was around.  They climbed on our shoulders and searched our pockets and didn’t offer to bite.  We didn’t think about rabies or any danger at all.
There is no proven 100% effective vaccination for humans exposed to rabies, but there is a nearly 100% effective antidote developed in Israel where street pariah dogs still carry the virus.  The only problem is that it costs $5000 for a course of treatment and not all insurers will pay for it.  Recently some sources noted that a single veterinarian had taken on the task of keeping a supply of the med on-hand, which brings the cost down some.
There are several diseases that develop into dog epidemics, sweeping through the streets, and in fact raccoons are susceptible to dog distemper and whole populations can be wiped out. It is a single-stranded RNA virus of the family paramyxovirus and thus a close relative of measles and rinderpest.  Despite extensive vaccination in many regions, it remains a major disease of dogs.  
As far as I know, people don’t catch it, but when the puppies born under our studio got it and died, I burned their bodies.  I’ve had measles.  Maybe that protected me.  If dog distemper mutated in a way that allowed the dog distemper virus to infect humans, we might be looking at something very ugly indeed. 
(Don't worry -- photoshopped.  I hope.)

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