Tarantula venom causes paralysis in humans?

[Moltar]

I'll stay away from the anaphylactic shock debate other than to say i don't think you guys are comparing apples to apples. On the subject of necrosis: If i personally were bitten by a male sydney funnel web spider (latin?) i'd be thanking my lucky stars to still be alive in time for tissue necrosis to set in. The discovery channel told me you can die within an hour without antivenom.

 

[DrAce]

I'll stay away from the anaphylactic shock debate other than to say i don't think you guys are comparing apples to apples. On the subject of necrosis: If i personally were bitten by a male sydney funnel web spider (latin?) i'd be thanking my lucky stars to still be alive in time for tissue necrosis to set in. The discovery channel told me you can die within an hour without antivenom.

I think you're right. Both Crotalus and I agree that this is not worth worrying about. I merely have been told that the localised swelling is a local immune response, and that anti-histamines are usually effective in reducing it. Who knows. I also maintain that it is possible (just possible) to have an alergic shock to something that a spider jabs into you, and those peptides are possible. Not a medically significant problem.

You heard what I heard about the funnel web spider. I've seen one in Sydney, and they're angry little buggers too.

 

[Nitibus]

Absence of evidence is not evidence of absence.

Great now you'll tell me the loch Ness Monster and Big-foot do exist !


Isn't all science ( other than physics in most cases ) just assumptions that haven't been proved wrong ? Science is a thoery with an absence of refutable evidence ? You can't refute what doesn't exist...like the Loch ness monster

 

[DrAce]

Great now you'll tell me the loch Ness Monster and Big-foot do exist !


Isn't all science ( other than physics in most cases ) just assumptions that haven't been proved wrong ? Science is a thoery with an absence of refutable evidence ? You can't refute what doesn't exist...like the Loch ness monster

Yes, although you can attach a likelyhood to some events. Some evidence for the possibility of an immune response exists. There is none for bigfoot of the loch-ness.

 

[Crotalus]

Again, Crotalus. I'm not sure we're sparring AGAINST each other, as oposed to nit-picking...

However, we're not talking about everyone here. We're talking about someone who has an alergic shock reaction - something which by definition is rare. I, for one, would not like to say it's impossible, when there is a distinct possibility that it can happen.

A large chunk of the earth's population does not live in daily interaction with tarantulas - particularly the Australian species. I doubt that there are a million people LIVING on earth who have been been bitten by one, and these sorts of severe reactions are likely to occur in less-than-one-in-a-million chances.

On top of all this, the venom is not a highly purified substance, to my knowledge. There is a high chance that other proteins are present, any one of which are not-human, and therefore likely to induce a reaction.

Again, I agree it's unlikely, but saying "it's never happened" is like a Ukranian Engineer working for Chernobyl saying "it's never happened so far...".

Absence of evidence is not evidence of absence.

I completely and utterly agree that there is no reason to be concerned. I don't lie awake at night, worried about getting tick-paralysis, and I will not be concerned about spider bites. But the chances are there, and the logic behind the declaration that it's impossible is flawed.

Theres no sparring or nitpicking as far as I can see.
I agree that you never know what future holds but as today nothing shows that severe allergic reastions is some thing that we have to worry about - I prefer to look at the facts what we do know and build my opinion from that.
Tick diseases are a fact, allergic responses to tarantula venom is not - australian or not.
Absence of evidence is a better indicator then "mights" and "coulds" in my book.

 

[Moltar]

Ya. I thought you needed proteins for anaphalaxis to occur and T venom has peptides, not proteins. I didn't read all the quoting that was going on up there so maybe you covered it already.

Normally when i see a cool bug i make a beeline for it. (pun?, no...) but if i saw an angry SFW i'd scream like a little girl and run away. Can't imagine what it must be like having something that feisty and venomous be so common in an urbanised setting like that.

 

[Nitibus]

Yes, although you can attach a likelyhood to some events. Some evidence for the possibility of an immune response exists. There is none for bigfoot of the loch-ness.

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[Crotalus]

I'll stay away from the anaphylactic shock debate other than to say i don't think you guys are comparing apples to apples. On the subject of necrosis: If i personally were bitten by a male sydney funnel web spider (latin?) i'd be thanking my lucky stars to still be alive in time for tissue necrosis to set in. The discovery channel told me you can die within an hour without antivenom.

Here you have bite records from funnel webs. Note the parts where they mention allergic reactions and necrosis:

http://www.inchem.org/documents/pims/animal/atrax.htm

 

[DrAce]

Ya. I thought you needed proteins for anaphalaxis to occur and T venom has peptides, not proteins. I didn't read all the quoting that was going on up there so maybe you covered it already.

Normally when i see a cool bug i make a beeline for it. (pun?, no...) but if i saw an angry SFW i'd scream like a little girl and run away. Can't imagine what it must be like having something that feisty and venomous be so common in an urbanised setting like that.

There is only one difference between peptides and proteins - size, but there is no threshold where one becomes the other. A protein is a big peptide.

You CAN get an immune response from a small peptide. There are even studies (Thoth posted some in a posting referenced above) where there is evidence of elevated immune markers after a bite.

I.e. it's possible, and all the markers are there.

ANY time there is an immune response, there is the possibility of it going to allergic shock. That, unfortunately, is a fact.

 

[DrAce]

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I see nothing to allow the possibility of a giant humanoid or an ancient monster.

 

[Nitibus]

ANY time there is an immune response, there is the possibility of it going to allergic shock. That, unfortunately, is a fact.

That being said, since urticating hairs are a immune response. Then it should be possible for people to go into allergic shock from urticating hairs ? Is that correct ?

PS. I'm no scientist


P.S.S. I'll stop goofing around with big foot now

 

[DrAce]

That being said, since urticating hairs are a immune response. Then it should be possible for people to go into allergic shock from urticating hairs ? Is that correct ?

PS. I'm no scientist


P.S.S. I'll stop goofing around with big foot now

Theoretically, yes. Although that would be initially slower.

Here is a paper indicating the suspected Anaphylaxis from caterpillar hairs.

This site (medical in nature, but not one I've seen before), indicates about half way down that anaphylaxis is known from hairs.

 

[Crotalus]

Atleast the local reaction are similar
If you inhale them I would think the swollen throat is a result of the hairs location

edit: Note the article says the word "may" - not "have" so no evidence here either for anaphylaxis really occured. Just assumtions.

 

[Scott C.]

Thanks Doc...

I recognize that things can happen... I was just wondering if anything had changed that would give one reason to believe it will happen.

Cheers guys,
Scott

 

[dragonblade71]

"As always, it's a question of what you feel comfortable dealing with. If you feel you can keep yourself safe, and the risk is acceptable, then go for it. If not, there are loads of other species out there!"

As I live in Australia, I have no choice but to obtain an Aussie tarantula. Well at least that makes my choices easier when I go spider shopping!

 

[Brettus]

As I live in Australia, I have no choice but to obtain an Aussie tarantula

At least we don't have to put up with urticating hairs

 

[Buckwheat]

I am not an expert but my dad has been keeping tarantulas for over 35 years and I would have to say that concerning tarantulas that are currently in the pet trade that there would be none that could produce any real effects other than for someone that might already have associated problems concerning stings or bites. Those people should either not be keeping anything that might cause a reaction or should not handle anything that can bring on that type of thing for them. I've been bitten more than a few times and have never had any type of reaction whatsoever. Just personal experience here.

 

[DrAce]

I am not an expert but my dad has been keeping tarantulas for over 35 years and I would have to say that concerning tarantulas that are currently in the pet trade that there would be none that could produce any real effects other than for someone that might already have associated problems concerning stings or bites. Those people should either not be keeping anything that might cause a reaction or should not handle anything that can bring on that type of thing for them. I've been bitten more than a few times and have never had any type of reaction whatsoever. Just personal experience here.

*sigh*

I fear I really have had a point missed. I'm going to step them out one by one:

There is no medical reason why you would be concerned about tarantula bites, at least rationally.

You should be aware, in the back of your head, that there is a whiff of a possibility that there may be a bad reaction to one, however.

The fact that there has been no recorded case, on the arachnoboards, of a severe allergic reaction to a bite is not reason to suspect it has not happened.

Not all anaphylaxis cases are recorded in journals. They are not all written up where google can get them. Not being able to find a case does not mean it can't happen.

There are proteins (call them peptides for all I care, there is probably a tertiary structure to them) in venom which may well be able to produce an allergic reaction.

There is some evidence to suggest that there is an allergic response to a bite - although it is not clear what the reaction was to.

An injection of venom, as far as I am aware, is not a highly purified jab of one protein, any more than urine is a single chemical in solution.

Someone with a sensitivity might not know it, and might get a bite and have a bad reaction. It's unlikely, but possible. Not something to worry about, but be aware of.

 

[Venom]

Dr Ace, zero cases of anaphylaxis in the litterature (and there are no shortage of bite cases from those spider species) might give us a hint that we can rule it out.
So, unless someone provide documented cases I think its correct to say it doesnt cause it.

As you state yourself in your first reply here:
"The magic words in that website are all there "Could" and "might"."

I choose to leave those words out and let facts speak for itself.

But you use this same approach to rule out the possibility of a tarantula bite ever causing a death, even with extenuating factors involved. Since I disagree with your position on that subject, I don't think I can agree with your logic here either. I think it's a case of exaggeration on both sides: you are saying it's flat out impossible, and DrAce is saying it's definitely possible. His logic is based on evidence of chemistry, and yours on observation of non-occurrence of anaphylaxis.

I'm going to take the middle road and acknowledge the evidence of both, but the conclusion of neither: it is chemically possible for a reaction to occur, but all evidence suggests this to a very remote, unlikely possibility. It's not impossible, the chemistry shows it isn't impossible. However, not knowing of T-induced anaphylaxis doesn't mean it hasn't happened, or that it could not happen. But it shows it is unlikely to happen.

So in a way, I agree with both of you, but I'm not going to worry about an allergic reaction myself, and I'm not going to advise people to consider it among tarantula defense risks.

What I do advise people to consider is their own health. I don't feel that a tarantula has the potency to kill a healthy human of non-tender years, at least not to any probability that we need to consider. What I do consider possible, after reading many bite reports from a range of species, is that tarantula bites can be "medically significant,"--not life-threatening in and of themselves, but potentially so when combined with other, already serious medical conditions. Body-wide muscle cramping isn't too dangerous...but if you have muscular dystrophy, it's a different story. A tight chest and some breathing strain isn't going to kill you, but if you have cystic fibrosis or COPD, it's not so clear what may happen. Same goes with S.calceata-induced heart irregularities and heart disease patients, or severe swelling from poecs and diabetes patients, or neurological effects with MS patients. The tarantula bite taken alone is not fatal, but it might, in some species, aggravate or contribute to a pre-existent condition to the degree that one's life could conceivably be in danger.

It's not a great leap of logic, and we have evidence both for the T bites causing certain effects ( bite reports, which ARE good sources of evidence ), and of certain diseases having effects along the same lines, or compromising systems in ways that leave a vulnerability to Tarantula bite effects. The only type of observed evidence we lack is what happens when diseases and T-bites interact, and with more and more people entering the hobby, it may not be long before we hear of this. Thus, I think common sense should compell us to advise novice hobbyists of the effects certain tarantulas can have, and the risks of interaction with similar diseases that they may pose.

 

[DrAce]

I think that's a very reasonable position, Venom.

Incidentally, I'm again repeating that it's not likely, but possible.

On a different note, Venom, there is a lot of stuff for you to respond to in the watering hole.