Toddler Bite and Tetanus

[ftmomma]

My toddler was just bit on the forearm by his cousin. It did not break the skin (but looks like JAWS came by for a visit!) and I am not worried at ALL......

But talking with my SIL....she felt bad and was looking online about what to do for "human bites" and of course the rec is to "make sure tetanus shots are up to date".

WHY is that recommended? It is my understanding that tetanus could not survive where there is oxygen...and there is definitley oxygen inside someones mouth....right?

Again, I'm not concerned at all...but just want to check my facts when explaining why I'm not worried...make any sense?

I would think a possible infection might occur after a deep bite, but not tetanus...please advise! Thank you!

[dymanic]

Originally Posted by ftmomma

It is my understanding that tetanus could not survive where there is oxygen...and there is definitley oxygen inside someones mouth....right?

What matters is whether there is oxygen in the wound.

I would think a possible infection might occur after a deep bite, but not tetanus

Statistically, the risk of tetanus may be regarded as small. The deeper the bite, the greater the risk. If the child is vaccinated, forget it. If not, you're playing the odds. They're pretty good odds, but among the unlucky, the case fatality rate in the U.S. is presently about eleven percent. In some undeveloped countries, it's much, much higher.

The risk of developing other types of infection from a human bite are significantly greater, and while they're not likely to be fatal, they can be pretty serious. Human bites are nothing to screw around with.

You might want to ask your SIL if cuz has had a rabies shot. (Then again, you might not.)

[attachedmamaof3]

It didn't break the skin.

Tetanus is not a factor.

[Emmeline II]

There are an average of 43 cases of tetanus a year and 0-2 deaths (in the US). Tetanus needs an anaerobic environment to thrive; a bleeding wound is not that environment. Tetanus is a disease of the elderly and those who otherwise have poor circulation (like diabetics). The only child cases I have read are of newborns who contracted it through something used on their cords.


If the bite did not even break the skin then it is not an issue at all.

[dymanic]

Originally Posted by Emmeline II

To thrive tetanus needs oxygen, that is why if a wound bleeds tetanus is not a concern.

Due, presumably, to the presence of oxygenated blood. There's a problem with that theory: it's free oxygen that inhibits growth of the bacteria, and oxygen in blood is bound to hemoglobin.

Tetanus is a disease of the elderly and those who otherwise have poor circulation (like diabetics).

We examined that in some detail in the other current thread on tetanus, and while my favorite debating partner has made an admirable effort to establish a connection between tetanus and poor circulation, I still feel that the evidence clearly supports the simpler explanation: the age bias is a reflection of vax status. If that weren't true, and poor circulation really was the more significant risk factor, you'd expect to see more cases among vaccinated elderly with poor circulation. As it is, tetanus is almost exclusively a disease of the unvaccinated.

If the bite did not even break the skin then it is not an issue at all.

The OP doesn't seem to have been the least bit confused about that, and made it clear that her fact-finding mission was for informational purposes only.

[mamakay]

What's wrong with it being multifactoral?

I still feel that the evidence clearly supports the simpler explanation: the age bias is a reflection of vax status. If that weren't true, and poor circulation really was the more significant risk factor, you'd expect to see more cases among vaccinated elderly with poor circulation. As it is, tetanus is almost exclusively a disease of the unvaccinated.

Your argument doesn't work for diabetics.

"If poor circulation was a factor in diabetics getting tetanus, you'd expect to see more fully vaccinated diabetics getting tetanus."

Or are we nitpicking over what's "the" biggest factor?
Could we cal it 50/50 (or 30/30/30)? "The elderly have a high incidence of tetanus because they're undervaccinated AND have poor circulation and weakened immue systems"?

http://www.journals.uchicago.edu/doi/pdf/10.1086/313792

Some Unique Aspects of Infections in the Elderly

Risk factors and common infections. Older persons generally
have greater susceptibility to infections than younger
adults.

Several studies have shown
that certain infections occur more often in elderly persons; morbidity
and mortality from infections are also higher that they
are among younger adults [8–11]. Urinary tract infections,
lower respiratory tract infections, skin and soft tissue infections,
intra-abdominal infections (cholecystitits, diverticulitis, appendicitis,
abscesses), infective endocarditis, bacterial meningitis
tuberculosis, and herpes zoster appear to have a special predilection
for elderly persons.

That has GOT to be a part of why they get more tetanus. There's no way around that.

Also...

http://microbiologybytes.wordpress.c...ridium-tetani/

Clostridium tetani infections are almost invariably found in anaerobic wounds, but in many cases the site of entry of the spores is minor and not found by the clinician. Nevertheless, the bacterium must interact with the host tissues and evade the immune response for a sufficient period to allow toxin production.

Weakened immune system + poor circulation = more tetanus in diabetics and the elderly.

There are factors at play with diabetics and the elderly outside of vaccination status. Not that vaccination status doesn't play perhaps the biggest part for them, as well, but it's not the only factor.

[dymanic]

Originally Posted by mamakay

Could we call it 50/50 (or 30/30/30)? "The elderly have a high incidence of tetanus because they're undervaccinated AND have poor circulation and weakened immue systems"?

I could maybe agree to 50/50 if it were phrased like this:
"The elderly have a high incidence of tetanus because they're undervaccinated AND due to a higher age-specific incidence among the elderly of Type 2 diabetes and other vascular diseases capable of producing ischemic ulcers which may provide an entry point for tetanus spores". But I'd still reserve the right to quibble about it being exactly 50/50, of course.

As for weakened immue systems, I still haven't found anything useful on the immunogenicity of natural tetanus toxin. I believe that "immune response" in this statement: "the bacterium must interact with the host tissues and evade the immune response for a sufficient period to allow toxin production" refers to those aspects of the innate response you were invoking (in the other thread) when you said: The immune system just clears a lot of stuff out [ ] as "gunk".

There are factors at play with diabetics and the elderly outside of vaccination status.

As far as diabetics, the reason is obvious, as previously noted (numerous times). As far as "the elderly" -- okay. But whatever those factors may be, they don't seem to be significant enough to even show up in the epidemiology against the background of vaccination status. The vaccine is nearly 100% effective. At the risk of making broad generalizations, it can be stated simply: If you don't get a hole in ya, you're not going to get tetanus. If you're vaxed, you won't get tetanus even if you do get a hole in ya.

Check it out:
Diabetic patients constituted 12% (16/130) of the 130 reported cases of tetanus during 1998--2000
Eleven of the 16 patients with diabetes had an acute injury; four had gangrene or ulcer; and one had no wound reported
http://www.cdc.gov/MMWR/PREVIEW/MMWRHTML/ss5203a1.htm

[mamakay]

I could maybe agree to 50/50 if it were phrased like this:
"The elderly have a high incidence of tetanus because they're undervaccinated AND due to a higher age-specific incidence among the elderly of Type 2 diabetes and other vascular diseases capable of producing ischemic ulcers which may provide an entry point for tetanus spores". But I'd still reserve the right to quibble about it being exactly 50/50, of course

Fair enough.


I've read some case reports on wounds that harbored both staph and tetanus...I'm guessing the staph proliferated, creating a pocket of dead WBCs, and that was how the tetanus spores got a chance to germinate?
Is pus an anaerobic environment? If so, that's another part of how a generally cruddy immune system could up one's chances of developing tetanus, I think.

I believe that "immune response" in this statement: "the bacterium must interact with the host tissues and evade the immune response for a sufficient period to allow toxin production" refers to those aspects of the innate response you were invoking (in the other thread) when you said: The immune system just clears a lot of stuff out [ ] as "gunk".

That's sort of what I was thinking....but do bacterial spores "interact" with anything?
I'm presently trying to see how tetanus's other virulence factors operate...it might excrete enzymes mid-germination to avoid clearance or something.
I'm also generally wondering how t-tox works to it's advantage???
How does that toxin benefit tetanus? It has to "do" something else besides killing it's host.When tetanus lives in the guts of horses, does the toxin help push out e. coli or something like that?
It has to do something useful at least some of the time...you'd think...

So much to ponder...lol

[dymanic]

Originally Posted by mamakay

I've read some case reports on wounds that harbored both staph and tetanus...I'm guessing the staph proliferated, creating a pocket of dead WBCs, and that was how the tetanus spores got a chance to germinate?
Is pus an anaerobic environment? If so, that's another part of how a generally cruddy immune system could up one's chances of developing tetanus, I think.

I suppose. Another way of looking at it is that the longer a wound takes to heal, the greater the opportunity for innoculation to occur.

How does that toxin benefit tetanus?

I'm always inclined to ask the same sort of question, but here, it may be good to reexamine the initial assumptions. A not-too-distant relative of Clostridium tetani, Clostridium botulinum, also produces a substance which acts as an extremely potent neurotoxin in humans (though its effect is essentially the opposite of tetanospasmin, the principle toxin produced by the tetanus bacterium). This is clearly a sophisticated evolved bioweapon, but considering that Botulism rarely infects human tissue directly, what could the bacterium possibly gain by poisoning humans? The answer is: nothing. Botulism is a soil bacteria, and its bioweaponry is designed to confer an advantage in that environment. The specific way in which the toxin causes paralysis in humans may be completely unrelated to its actions on the intended target(s). The occasional human casualty is an innocent bystander. Now let's return to tetanus. Hey, what do you know -- it's a soil bacteria too. Puzzle solved.

[mamakay]

I think tetanus is a soil bacteria mainly because it lives in the guts of animals, though.
Either way, I'm unable to find anything about what tetanus "uses" it's toxin for in any environment. Maybe I'm not using the right keywords.

The occasional human casualty is an innocent bystander.

I tend to think of all fatalities from pathogenic bacteria like that.

[Emmeline II]

Are we making an assumption that the elderly are under vaccinated? Do we know the vax status for each case of tetanus each year? I know many elderly through my fraternal organization and they see the doctor six or more times a year. Each visit is an opportunity to vaccinate and tetanus seems to be the one vax that has been pushed on adults in the past.

[dymanic]

Originally Posted by Emmeline II

Are we making an assumption that the elderly are under vaccinated?

Yes. Well, the assumption is that the CDC's coverage estimates are accurate.

Do we know the vax status for each case of tetanus each year?

No. We do know that among those for whom vax status can be confirmed, cases of tetanus are exceedingly rare.

I know many elderly through my fraternal organization and they see the doctor six or more times a year. Each visit is an opportunity to vaccinate and tetanus seems to be the one vax that has been pushed on adults in the past

Many people are learning that these days you have to be your own health care advocate, because -- as crazy as it may seem -- doctors cannot always be counted on to stay on top of things.

[dymanic]

Originally Posted by mamakay

I think tetanus is a soil bacteria mainly because it lives in the guts of animals, though.

It could be that it lives in the guts of animals mainly because it is a soil bacteria.

Either way, I'm unable to find anything about what tetanus "uses" it's toxin for in any environment. Maybe I'm not using the right keywords.

I'm betting it's because nobody knows. Besides tetanospasmin (which produces the clinical symptoms of tetanus) the bacterium also produces another, tetanolysin, and they don't even know for sure what that does in humans.

[Emmeline II]

Corrected post #4. Tetanus needs an anaerobic environment to thrive .

[mamakay]

Originally Posted by dymanic

It could be that it lives in the guts of animals mainly because it is a soil bacteria.

I'm betting it's because nobody knows. Besides tetanospasmin (which produces the clinical symptoms of tetanus) the bacterium also produces another, tetanolysin, and they don't even know for sure what that does in humans.

Well, it looks like we're on our own guessing what's going on here. Which is quite surprising, really. I figured the life cycle of this famous bacteria would be a subject about which a great deal was known. Oh, well.

I've read a bunch of things that said "Tetanus can be found living in the soil, especially heavily manured soil." Assuming the "especially" part is based on lots of good data, I'm going to guess that tetanus has probably adapted to surviving by moving from the guts of animals, to the soil, back into the gut, etc. Just a guess, though.

[mamakay]

Sort of like this bacteria:
http://jb.asm.org/cgi/content/full/188/7/2692

I'm still looking to see if it's ever been studied. I guess we just need to know if the bacteria germinates and then 're-spores' (or whatever it's called) in the gut, or if it's just spores from the soil that can be found in the gut.

ETA:
Hahaha...it's called "sporulation".
http://medical.merriam-webster.com/medical/sporulation

Sounds like a word I'd make up to describe re-sporing...lol

[dymanic]

Originally Posted by mamakay

Well, it looks like we're on our own guessing what's going on here. Which is quite surprising, really. I figured the life cycle of this famous bacteria would be a subject about which a great deal was known. Oh, well.

Humans tend to be self-centered by nature, so it's no big surprise if interest in a microbe like C. tetani begins with the effects of its toxin on the human body and how to prevent and treat that. Once enough is known about it to provide adequate means of dealing with it, it's also no big surprise if much of the interest ends there, and most of the research moves off in the direction of the next pesky critter that's giving us grief. You'd think that would still leave at least a few individuals of the obsessive biogeek variety who'd be motivated to keep digging if only in the hope of achieving some of the glory that goes along with uncovering something nobody's ever uncovered before, no matter how useless. Maybe even a very few who'd do it just for fun. So many bugs, so little grant money.

I've read a bunch of things that said "Tetanus can be found living in the soil, especially heavily manured soil." Assuming the "especially" part is based on lots of good data, I'm going to guess that tetanus has probably adapted to surviving by moving from the guts of animals, to the soil, back into the gut, etc. Just a guess, though.

It probably more or less comes down to: "what does the sucker eat?" -- and I'm going to guess the answer is: "like its close cousin, C. botulinim, pretty much anything organic, in various stages of decomposition, and if it's rich in iron, so much the better, because the iron removes oxygen by binding it in rust". One thing you see over and over is "The toxin has no known useful function to C. tetani", which doesn't mean it doesn't have a function, just that we don't know what it is. If I wanted to get creeped out, I'd think about possible useful functions some humans might find for such highly toxic substances as those produced by these organisms, because culturing them doesn't look like very tricky work. I don't know about purifying them. Just googling that probably earns ya a special spot in some FBI database.