|
1-10 of 11 messages
|
Page 1 of 2
Next
|
|
Rattlesnake Bites Becoming More Dangerous
|
Reply
|
|
by tigers9 on May 12, 2008
|
Mail this to a friend!
|
http://www.kpho.com/news/16008917/detail.html
Rattlesnake Bites Becoming More Dangerous
POSTED: 10:24 am MST April 26, 2008
PHOENIX -- More than a half-dozen people have been bitten by rattlesnakes in the last two weeks, and doctors are now warning that the venom is becoming more poisonous.
Russ Johnson nearly lost a finger after a severe rattlesnake bite eight years ago.
"It was just like wave after wave of pain as venom pulsed through the body," Johnson said.
Johnson still works with reptiles at the Phoenix Herpetological Society, but he said he's more careful now.
"I've broken eight bones and to be honest with you, after I got to the hospital, I'd rather have broken all eight bones again," Johnson said. "I did ask them to cut the finger off, but by then it was too late. It was already up to my elbow.
Valley doctors are starting to see more patients like Johnson, becoming critically ill after rattlesnake bites, compared to just a few years ago.
"These patients commonly have very low blood pressure. Many times they're lethargic or unconscious," said Dr. Steve Curry of Banner Poison Control.
Similar trends are appearing in southern Arizona, Colorado and southern California.
"The reason for this isn't clear to us," Curry said. "Snake venom can't just change across the country all at once."
Whatever the reason, Curry says rattlesnake bites are becoming more dangerous. That means it's even more important for someone who's bitten to get medical help right away.
|
| |
|
RE: Rattlesnake Bites Becoming More Dangerous
|
Reply
|
|
by earthguy on May 12, 2008
|
Mail this to a friend!
|
What a bunch of malarky. Evolution doesn't take place overnight. There are some reasons that bites could appear to be increasingly dangerous. One is that we are beginning to better understand venom through the work of BGF and others. Another is that doctors in general are beginning to discuss this more, primarily because of antivenin shortages. But my two favorite (more plausible) possibilities are that antivenin itself may be getting less effective (Crofab is definitely better at preventing allergic reactions in patients, but its efficacy as an antivenin is dubious at best when compared to Wyeth) and American's health in general is worsening. So in short, if bites are in fact worsening it is due to the health care issues in the United States, not Evolution.
But thanks for posting, Z.
|
| |
|
RE: Rattlesnake Bites Becoming More Dangerous
|
Reply
|
|
by Cro on May 12, 2008
|
Mail this to a friend!
|
I sure would like to see a comparison of the results of CroFab verses Mexican made Biocon Anti-Venom.
I am betting that the study would show that it is not the venoms evolving, so much as it is the problems with CroFab.
Best Regards JohnZ
|
| |
|
RE: Rattlesnake Bites Becoming More Dangerous
|
Reply
|
|
by JoeCrotalid on May 12, 2008
|
Mail this to a friend!
|
Having just had the opportunity to listen to Bryan at the Tucson Venom conference he would not only tell you many snakes are evolving their venoms, but that some snakes and lizards thought to be non-venomous are actually developing weak venoms such as some of the colubrids and Iguana species. Another factor to be considered is that venom potency can differ even among the same species as pointed out by Minton which could account for differences in envenomations.
Yes! CroFab does have its drawbacks as a Fab1 antivenom, which is why it requires maintenance dosing, but again the upside is the lower risk of allergic reaction as opposed to the Wyeth Fab2 polyvalent. Another way to connect with Elda is through the Natural Toxins Research Center
|
| |
|
RE: Rattlesnake Bites Becoming More Dangerous
|
Reply
|
|
by earthguy on May 13, 2008
|
Mail this to a friend!
|
Joe,
I didn't say that snake venom is not evolving, I said that it is not evolving at the rapid pace implied in the article. I am 100% certain that Doc Fry would agree with me on this one.
|
| |
|
RE: Rattlesnake Bites Becoming More Dangerous
|
Reply
|
|
by JoeCrotalid on May 15, 2008
|
Mail this to a friend!
|
Joshua
The article really doesn't say anything about venom evolving but rather as with most media, it makes a broad statement that patients are becoming sicker from bites without covering the facts, ie. time of the year, juvenile vs. adult, bite location on individual, species, time to treatment, health issues in patients, etc.
I will give you the fact that venom is not evolving at quantum speeds, but nature does have a way of speeding up the evolutionary process in order for a species to survive.
My point here is that this is just another poor media attempt on the topic of snakebites that was written without all the facts again once again blaming the snake. Yet! What about the ignorance of many people who go out and try to handle snakes without knowing what they're doing-that's what is making snakebites more dangerous.
|
| |
|
RE: Rattlesnake Bites Becoming More Dangerous
|
Reply
|
|
by FLherp on May 18, 2008
|
Mail this to a friend!
|
The Wyeth Crotalidae Polyvalent is a whole IgG, not a F(ab)2 product. It still maintains the F(c) fragment which activates the complement of the immune system, thus the F(c)- for fragment complement activating. Some whole IgG products that are processed differently from Wyeth have an excellent safety profile with low pyrogenecity.
The only difficulties I have seen with Crofab is the difficulty in controlling coagulopathy, albeit this is a serious problem. It is expensive and may need to be administered in copius quantities in some instances. Much of the problem confronting physicians when treating snakebites is the lack of familiarity with antivenom and treatment of snakebites. There is a reluctance to use the medication and a worry that it will result in anaphylaxis. Anaphylaxis is treated in ERs everyday, snakebites are relatively rare. It does not seem to enter the equation that allergic/anaphylactic reactions can occur with many meds that are prescribed everyday or OTC meds that you can buy at the grocery store.
Are snakebites really becoming more dangerous? Is this based on careful research or some anecdotal information? One of the major problems with much of the information concerning snakebites is that it is anecdotal, not based on formal research. The serious bites are the ones that are noted, not the mundane problem that was easily treated, or the dry bites, or the bites from misidentified species. I think I will withhold judgement until I see something a bit more convincing, then I may jump on the snakebites are more dangerous bandwagon.
I think Bryan's research shows that the evolution of venom is actually quite ancient; that it occured prior to the divergence of the 'more' evolved 'venomous' species from the 'non-venomous' species, not that it is a recent occurence. If indeed there are new toxins in the venom arsenal of rattlesnakes it is likely to stem from the expression of genes previously unexpressed in rattlesnakes, vs. hybridization or newly evolved genes. Crotalidae are more "highly" eveolved than the Elapidae and may have likely had these unexpressed genes in the 'recipe' for some time. Nature is not discrete and does not fit into the tidy boxes we like to use to divide the world up.
|
| |
|
RE: Rattlesnake Bites Becoming More Dangerous
|
Reply
|
|
by Cro on May 18, 2008
|
Mail this to a friend!
|
As far as venoms evolving faster, I ran into an interesting article on Science News that suggests that evolution can speed up to "warp speed" under specific conditions.
The article is at:
http://www.sciencedaily.com/releases/2008/05/080515120759.htm
Although it deals with "Reverse Evolution" in stickleback fishes, it fits right in with what Jeffrey said about the "expression of of genes previously unexpressed in rattlesnakes."
Based on the stickleback study, we could make the assumption that venoms were perhaps stronger sometime in the past, and are now expressing an genetic "memory," and coming back stronger.
Or, we could assume that the potential was always there, was never expressed, but is now being expressed. The idea that there are unused ingredients in the cupboard is interesting. Perhaps the snakes never considered using paprica untill now, and have changed the recipy.
In both cases, it would be interesting to look at climactic changes that might be causing these changes in venoms. Perhaps the food items the snakes prey upon are changing, and thus stimulating a change in the venoms ?
Could it be that there is a decline in lizard populations, and an increase in rodent populations, in parts of the country, that has not been well documented to the extent that it can be shown to be changing the diets of venomous snakes ?
This is a fascinating topic. I would love to hear what others here think about the rapid reverse evolution in the sticklbacks and how it might relate to the evolution of venoms.
Best Regards JohnZ
|
| |
|
Email Subscription
You are not subscribed to this topic.
Subscribe!
My Subscriptions
Subscriptions Help
Check our help page for help using
, or send questions, comments, or suggestions to the
Manager.
|
