This forum is for questions about medical issues and research aspects of
Hepatitis C such as, questions about being newly diagnosed, questions about current treatments, information and participation in discussions about research studies and clinical trials related to Hepatitis. If you would like to communicate with other people who have been touched by Hepatitis, please visit our new
Hepatitis Social/Living with Hepatitis forum
Bill
Dying traces of RNA on a tooothbrush cannot replicate in the absence of liver cells.
I don't wish to be rude but this is a dumb thread-you cannot reinfect youreself in the face of an active infection as you are litereally creating billions of viral copiies daily without the help of your toothbrush
A good tip to avoid reinfectioin after you have cleared is don't shoot up!
-------------------------
Call me obsessive, but I changed toothbrushes weekly during treatment. They only cost a dollar each so I figured better safe than sorry. Same with razors. I used disposables and one use only.
But saying that sharing toothbrushes is "one of the top" ways of transmitting the disease seems a bit of an overstatement, and I'm unaware of any study data that supports it. You only have to look here, where many have had hepatitis C for a number of years without knowing it, and still have not spread it to family members in spite of sharing personal items. That said, the prudent thing for anyone HCV positive would be not to share personal items. And this is a pretty common recommendation from most HCV information providers.
-- Jim
Conclusion: With sufficiently sensitive methods, a contamination with HCV-RNA can be detected at a large portion of toothbrushes used by hep. C patients. In spite of the low infection risk usually published for household contacts, transmission by contaminated every-day`s household objects appears to be possible.
We can not just let people think the only way they can get it is IDU ? what i do know is many peoples gums bleed when brushing their teeth so that is good enough for me to put it as a "top way of spreading"" and not to share toothbrushes. I guess you have no problem with sharing a toothbrush with a family member?
Personally any possibility is good enough reason for me to not take the chance of infecting my family. this is just my own opinion.
best of luck
---
OMG. Why ever would you say that? I posted no information about my own personal hygenic habits, and your suggesting this is rather insulting.
I simply responded to your opinion and misstatements about a study.
Regardless of your opinions and feelings that "We can not just let people think the only way they can get it is IDU ?" the proper thing to do is to point someone to the CDC or NIH for the information.
----
According to the CDC:
http://www.cdc.gov/hepatitis/HCV/HCVfaq.htm#section2
How is HCV transmitted?
HCV is transmitted primarily through large or repeated percutaneous (i.e., passage through the skin) exposures to infectious blood, such as
* Injection drug use (currently the most common means of HCV transmission in the United States)
* Receipt of donated blood, blood products, and organs (once a common means of transmission but now rare in the United States since blood screening became available in 1992)
* Needlestick injuries in healthcare settings
* Birth to an HCV-infected mother
HCV can also be spread infrequently through
* Sex with an HCV-infected person (an inefficient means of transmission)
* Sharing personal items contaminated with infectious blood, such as razors or toothbrushes (also inefficient vectors of transmission)
* Other healthcare procedures that involve invasive procedures, such as injections (usually recognized in the context of outbreaks)
---
According to the NIH:
http://digestive.niddk.nih.gov/ddiseases/pubs/hepc_ez/#2
How could I get hepatitis C?
Hepatitis C is spread by contact with an infected person's blood.
You could get hepatitis C by
Man offering another man a syringe.
You could get hepatitis C by sharing drug needles.
* sharing drug needles
* getting pricked with a needle that has infected blood on it (hospital workers can get hepatitis C this way)
* having sex with an infected person, especially if you or your partner has other sexually transmitted diseases
* being born to a mother with hepatitis C
In rare cases, you could get hepatitis C by
* getting a tattoo or body piercing with unsterilized, dirty tools
You can NOT get hepatitis C by
* shaking hands with an infected person
* hugging an infected person
* kissing an infected person
* sitting next to an infected person
He never mentioned toothbrushes but it's prudent to not share them, although most of us did. My husband and I inadvertently still do, despite our best laid plans.
Today, I believe IDU may be one of the main sources of HCV transmission but it was not the case in my generation, when transmission was often via medical and dental offices. I probably got mine through gamma globulin shots or a backstreet college deal to extract my impacted wisdom teeth at a rock bottom price. (In both cases, I got wildly sick.)
I would call those routes some of the top ones for transmission in that time period.
s/b: "I would call those routes some of the top ones for transmission at that time, barring known risk factors like transfusion and IDU."
Greatbird, didn't mean to ruffle your feathers and by no way was I questioning your hygine. The way your original post sounded was sharing toothbrushes was no big deal. That is why I asked if you would let a family member use your toothbrush. Since you didn't answer the question I will assume you would not have a problem with it.
Lets just leave my "opinion" as this: NO one really knows how many other ways this disease can spread so why not just be extra careful if you have it. By this I mean if there is a remote possibility use common sense and avoid exposure.
DDW Liver Conference
San Francisco,
HEPATITIS C - TRANSMISSION BY TOOTHBRUSHES: A MYTH OR A REAL POSSIBILITY?
Reported by Jules Levin
Guntram Lock, Martin Dirscherl, Florian Obermeier, Cornelia M. Gelbmann, Claus Hellerbrand, Antje Knoell, Juergen Schoelmerich, Wolfgang Jilg, Regensburg, Germany
Introduction: Up to 40% of patients with chronic hepatitis C have no obvious risk factor for the disease. Unconventional ways of transmission such as for example infection by tattooing or sharing of possibly infected household objects have been discussed to play a role for these community acquired forms. Thus, patients with hep. C are advised to take care not to share objects like razors, nail-scissors or toothbrushes with their household members. In this study, we prospectively examined the contamination of toothbrushes in patients with chronic hep. C as a model for a possible unconventional way of transmission.
Patients and methods: 30 consecutive patients with chronic hep. C were included in the study. Around 2 ml of saliva were obtained before and after brushing the teeth under controlled conditions for 2 minutes. After toothbrushing, the toothbrush was rinsed in 2 ml of NaCl. RNA was isolated with the QIAmp Viral RNA mini Kit (Qiagen) and HCV-RNA was detected by the COBAS AMPLICOR HCV - Test v2.0. Results were qualitatively graded as positive or negative. Oral hygiene was classified as good, fair or bad, and the parodontose bleeding index (PBI) was determined by a dentist. Clinical, biochemical and histological parameters were related to the HCV results in saliva and toothbrush rinsing water.
Results: In 9/30 patients (30%), the "native" saliva (i.e. before toothbrushing) was positive for HCV-RNA, and in 11/29 patients (37.9%) saliva after toothbrushing contained HCV - RNA. In as many as 12/30 (40%) specimen of the rinsing waters of the toothbrushes HCV - RNA was positive. In 6 of these 12 patients, the "native" saliva had been negative for HCV RNA. Patients with HCV - RNA positive toothbrush rinsing water showed no significant differences to patients with HCV RNA negative rinsing water in respect to oral hygiene, PBI, histological grading or staging, coagulation parameters, ALT, bilirubin and quantitative HCV - viral load in the serum.
Conclusion: With sufficiently sensitive methods, a contamination with HCV-RNA can be detected at a large portion of toothbrushes used by hep. C patients. In spite of the low infection risk usually published for household contacts, transmission by contaminated every-day`s household objects appears to be possible. Considering the great epidemiological importance of hep. C, further examinations and maybe even legal instructions concerning publically used possibly infected objects such as razors in barbershops appear indicated.
editorial note: there is no evidence that HCV can be spread by saliva or by contact with a toothbrush with HCV in saliva on it. What about dried blood on a toothbrush or on a razor at home or in a barber shop? These are fair concerns.
------------------------------------------------------------
PA thoughtfully use the phrase "pet theory" and two things should be pointed out. First, the caveat is no known risk factors which immediately eliminates most probable means of transmission. And second, as stated, this is simply a pet theory because you will notice that dental work does not appear on either the CDC or NIH list posted by great bird, above. Personally, I would not be surprised that transmission has occurred, and even still does occur, in some dental offices. Or during other medical procedures per se.. I just don't see any evidence that it's a major cause of transmission, at any point in time.
One controversial source of infection for hepatitis C virus (HCV) involves the sharing of
contaminated implements, such as straws or spoons, used to nasally inhale cocaine and
other powdered drugs. An essential precondition for this mode of transmission is the
presence of HCV in the nasal secretions of intranasal drug users.
Methods
Blood and nasal secretion samples were collected from five plasma-positive chronic
intranasal drug users and tested for HCV RNA using RT-PCR.
Results
HCV was detected in all five blood samples and in the nasal secretions of the subject with
the highest serum viral load.
Conclusions
This study is the first to demonstrate the presence of HCV in nasal secretions. This
finding has implications for potential transmission of HCV through contact with
contaminated nasal secretions.
Transmission of HCV is known to occur through contact with contaminated blood, most
notably in the context of injection drug use, transfusion of blood products prior to 1992,
chronic hemodialysis, occupational exposure to blood, and nosocomial and perinatal
exposure. In addition, several studies have reported low levels of suspected sexual and
household transmission of HCV [2].
Although much is known about the routes of HCV transmission, nearly 15% of infected
individuals report no identifiable source of exposure. Unexplained cases are particularly
high among drug-users who have no history of injection risk and no other identifiable risk
factors [3]. One hypothesis that might account for the high number of unexplained HCV
infections among noninjection drug-users was proposed by researchers at the US National
Institutes of Health (NIH), who identified intranasal cocaine use as a significant risk
factor for HCV among volunteer blood donors [4]. They reasoned that HCV might be
transmitted through contaminated implements, such as straws or spoons, that are
commonly used to nasally inhale powdered drugs, including heroin, cocaine, and
methamphetamines. Chronic nasal inhalation of these substances (including the
adulterants they contain) can cause tissue deterioration and bleeding of nasal membranes.
Implements inserted into an eroded nasal cavity may come into contact with HCV-
infected mucus or blood, which may then be transmitted to an uninfected individual
sharing the same implement. The debate regarding this potential mode of transmission
intensified when the National Heart, Lung and Blood Institute (NHLBI) Retrovirus
Epidemiology Donor Study (REDS) was unable to confirm intranasal drug inhalation as
an independent risk factor for HCV [5]. These conflicting reports prompted the American
Association of Blood Banks (AABB) to add, and then shortly thereafter remove,
intranasal cocaine use from their list of criteria used to screen potential blood donors. A
subsequent review of the literature found serious methodological limitations with both the
NIH and NHLBI/REDS studies [6]. Although HCV has been detected in the saliva,
semen, and other nonserological fluids of some plasma-positive patients [7], no
virological studies have been undertaken to determine whether HCV is present in the
nasal secretions of intranasal drug users, a necessary precondition for internasal viral
transmission. Here, we report preliminary findings on the detection of HCV RNA in the
nasal secretions of plasma-positive chronic drug sniffers.
References Results and discussionPrevious studies have demonstrated the presence of
HCV in a wide variety of nonserological fluids [7,10]; for instance, HCV has been
detected in about 50% of saliva samples from plasma-positive individuals [11]. We
reasoned that HCV might be present in nasal secretions at a similar prevalence and would
therefore be detectable among a relatively small sample of viremic patients. Five
consecutive plasma-positive clinic patients were selected for study and each contributed
blood and nasal secretion samples for HCV RT-PCR analysis.
The RT-PCR results confirmed the presence of HCV in the blood of all five subjects. The
highest serum concentrations of viral RNA were detected in subjects 1 and 2 and the
lowest in subject 5 (see Fig. 1); these findings were consistent with patient record viral
loads. It is noteworthy that our assay detected HCV RNA in the serum of subject 5
(previously below the level of detection with commercially available assays), indicating
low-level viremia, and verifying the high sensitivity of our analysis.
Figure 1
HCV RNA detection from serum and nasal secretions of five intranasal drug users. A:
Ethidium bromide staining of DNA fragments; B: Southern blot hybridization
Significantly, HCV particles were also detected from the nasal secretions of subject 1
(Fig. 1). This subject, a 56-year-old African-American male, also exhibited the highest
HCV serum viral load (34 500 000 IU/mL). HCV was not detected in the nasal secretions
of the other four study subjects. This finding represents the first demonstration of the
presence of HCV RNA in nasal secretions.
Great care was taken to avoid sample contamination during all phases of the study. Blood
samples of known serology were collected from each of the five subjects and tested for
HCV RNA to confirm the validity of our laboratory procedures. The TRIzol assay used
on the nasal secretion samples in this study has been shown to be effective for RNA
isolation with a variety of other nonserological samples [11,12].
It is possible, , so are nail salons, dentists etc..
It is Blood to Blood.....In my opinion. My sons gums bled
all the time....a lot, even when not on tx. He bled a lot.
He was engaged to be married for 10 years. Having intimate
encounters. Marie is Fine. (blood in bodily fluids as Jim
might remember):)
Having raised a wonderful son.and daughter, .through the years (son) with hemophilia,
and a brother with hemophilia and Aids......
I can tell you in all honesty that I've cleaned more blood than
you can imagine. Probably more than some nurses.
I've given infusions in the vein..more times than I can count
for my son. I've even poked myself with his used needle on
accident. I'm negative.
My daughter is negative, they were raised together, they
did a lot of things....they never (that I know of shared tooth brushes)
however did share eating utensils and straws at times.
I even shared things with my son...lots of times......straws to sip
on etc.... held him, hugged him..kissed him,.helped him with many bleeds. Without gloves.
In my opinion, a toothbrush is the least of all the worries.
about transmission. It would not be on my top priority as long
as they are not shared.
For anyone....general hygeine, just change your toothbrushes
if they are left out in the open in your bathroom....for YOUR protection
against other viruses in the air . I only changed toothbrushes
may-be once every two months, while my son was living at home.
My son never was able to reach UND. for the first poster
whom we haven't heard from...(strange)?????
I Love my son and miss him dearly, he would not have
wanted anyone to get HCV...he was careful as he grew up.
Had he reached UND ...if ever...On the toothbrush matter,
it would be the farthest thing from my mind, of reinfection.
It is without a doubt something to be aware of...just like all the
other modes of transmission, however, not highly obsessive.
Take care all !!!
editorial note: there is no evidence that HCV can be spread by saliva or by contact with a toothbrush with HCV in saliva on it. What about dried blood on a toothbrush or on a razor at home or in a barber shop? These are fair concerns.
1. Right. No evidence that HCV can be spread by saliva
2. Something being a "fair concern" does not mean that it is an established mode-of-transit for the virus.
Whether we think it's a good idea to change toothbrushes often doesn't mean there is any basis in fact/research to support it. Presenting something as fact when it is opinion is wrong. Being prudent can be very right.
just for the record i do not believe in changing toothbrushes during TX. I did not. but i know my gums bleed when i brush my teeth so i would not share a toothbrush with my child. I would rather be safe then sorry.
as far as i'm concerned i made my point and offered "my opinion" and this will be my last comment in this thread.
God Bless
I used an electric one so I just changed the head daily. Was that compulsive? I didn't think so at the time.
Mike
http://venturesix.com/store/index.php?keywords=cheap%20toothbrushes&creative=3457814929&gclid=CP-Vl9zUxpoCFQKenAodVz34tA
You're right about the cost but sometimes you gotta either shoot big or stay home.
Mike
This was a very striking observation to me, and seems to speak volumes. To me it says, take care to clean up spilled blood, but don't obsess about transmission to others. Now that I'm thinking of it, our skin IS a great barrier to multitudes of bacteria and viruses, and unless someone near me has a cut, AND I didn't take care to clean up blood, AND they happen to touch it, WITH the hand with an open wound.... seems needless to say transmission isn't likely without blood to blood contact.
IMHO...which is pretty unlearned about this topic.
The only natural boar bristle brushes that I buy are horse brushes LOL. I'm with Trin on this one, sonic care
Mike
Tazuko Yuasa1, Gen Ishikawa2, Sei-ichi Manabe2, Sadayoshi Sekiguchi3, Kenji Takeuchi1 and Tatsuo Miyamura1
1 Laboratory of Hepatitis Viruses II, Department of Enteroviruses, National Institute of Health, 2-10-35 Kamiosaki, Shinagawa-ku, Tokyo 141
2 Asahi Chemical Industries Co. Ltd., 1-1-1 Uchisaiwaicho, Chiyoda-ku, Tokyo 100
and3 Hokkaido Red Cross Blood Center, Yamanote 2-2, Nishi-ku, Sapporo 063, Japan
To estimate the particle size of hepatitis C virus (HCV), a major causative agent of post-transfusion non-A, non-B hepatitis, we filtered plasma or serum samples through microporous cellulose fibres with different pore sizes. The amount of HCV particles in samples before and after filtration was determined by a quantitative reverse transcriptase polymerase chain reaction (PCR) method. Since there is no quantitative biological assay for HCV, except for that in chimpanzees, the HCV titre obtained from the PCR method was used in an equation constructed previously for application to filtration experiments with a flavivirus which is distantly related to HCV. The particle was estimated to be between 30 and 38 nm in diameter, although the possibility remained that larger HCV particles or HCV aggregates with a diameter of more than 39 nm might exist. Double-step filtration through microporous cellulose fibres with a pore size of 35 nm reduced the HCV content to below levels detectable by our PCR method, indicating that it is possible to eliminate HCV particles by simple filtration techniques.
to be continued
mb
Let’s go from there:
An HCV viron is estimated to have the length of between 30 and 40 nanometers.
Just an estimate there as these are too small for any device to really measure.
Some may be slightly bigger or smaller than others.
Current filtering devices can screen out most virions by using a 35 nm screening process so I’ll round up and say they maybe as big as 40 nm, the high end of the estimates.
Source is http://en.wikipedia.org/wiki/Nanometre........
With me so far?
OK>>>> .. <<<<<<
ok, you see the 2 periods above right? That distance between the is approximately 1 millimeter. That millimeter contains a million nanometers. 1,000,000 nanometers.
Ergo one viron at say 40nm divided into 1,000,000 equals 25,000 virons in the space of one linear millimeter.
Look at the dots again. You can fit at LEAST 25,000 or more virons between those 2 dots.
Remember the thread called “what do you think of this scary study?” in Medhelp just days ago?
That study said viral infection could occur with as few as 20-40 virons.
20 to 40 virons, and you can fit 25,000 between those two dots above!
How small then is the amount of blood then needed to grind back into your gums to reinfect you?
Can you see it? Can you detect or comprehend it’s tiny size?
I mean, if an amount so small we cannot see, nor even begin to imagine if honest, is all it takes to give the virus a chance to live in a new host….or the same old host…us….then why would we want to take that chance?
WHY?
Once I went UND I went to Dollar Store, where they had 6 packs of very decent toothbrushes for a buck, and I changed them weekly. If I changed them DAILY the cost would have been 50 bucks for the year.
Compare that to the suffering, the sides, the relationships strained or ruined…how can we even go there?
There is no comparison!
Maybe one needs to think about the alternative as possibly more suffering??
Just a thought.
Hand brushing works if done right, and it would cost 20 cents not 30 bucks to replace each brush.
For this I’d give up any electronic gismos.
For that matter, even 30 bucks seems like small change if you think about the possibility of getting reinfected or needing a transplant. How pennywise and pound foolish that will seem to a relapser heeding no cautionary tales…
I don’t know. I don’t want to look in that mirror and think, maybe if I’d done this differently or that.
I’d rather do my best now in every aspect so that regardless of outcome I can say I gave SVR my best shot!
If this seems anal well then shoot me, but an amount of blood so small we can’t imagine is all it takes to infect so what harm can precaution possibly do here.
Ask yourself this question….knowing NOW, that it only takes a 20-40 viron exposure to see healthy cells become infected…
Would you let someone else brush your teeth with something that “might” have even a hundred virons on it??
Would you let them rub that into your gums knowing those tissue cells open up and bleed easier than anywhere else on your body?
Would one do that?
Then by all means keep using that old brush….
to save yourself a few lousy “bucks”
and call those who take precaution names.
Rolleyes.
Yet I will take my brand of squirrelly precautions over the nonchalant attitude any day.
We are not scientists, and we do not understand all the methods of transmissions, so until we do, SHOULD we NOT be on guard?
I remember the day they put me under, and gave me plasma against my wishes…
And when I woke up I was furious and they ASSURED my, there was no way I could get Aids or anything from plasma. That was 20 years ago. It seems only yesterday they were that dumb…and it wasn’t long ago!
I’m wondering what 20 more years will do to our knowledge base.
So go with your instincts, and I’ll go with the current science, which only hints at, but doesn’t say for certain…
it’s not much,
but it’s better than hunches.
mb
but seriously though, when my dentist admitted the possible dental exposures, which very few will EVER admit, and he added that blood becomes airborne with sonic cleaning and is inhaled by those around...
when a dentist tells you this you start to get scared.
Especially when he looks as sober as a hanging judge while he's telling you.
After all...we know colds and flu are spread through the air...right?
Doesn't take many inhale molecules to get sick either.
but have we ever considered that HCV and HIV are also made airborne in these offices?
How many virion must one inhale to become infected? One study said 20-40 virons only but currently, in vitro, the
Answer is still unknown, but that doesn't mean it's a good idea to make a teaspoon an hour go airborne now does it?
Certainly didn't make sense to my dentist or hygenist...
I'm just assuming it's because they don't want our disease and have discovered something the NIH is not too keen on telling us...like that more of us got it from medical and dental procedures than from shagging or snorting something.
mb
What is a dollar store:)
And Trin, by all means.....shoot me twice:)
To be infected, the virus must enter our blood stream, and replicate in our liver.
To 're-infected' you would have to CLEAR the virus (be SVR), then introduce into your bloodstream new virus.
So if you clear the virus where do these live healthy virions come from?
Don't tell me you cleared the virus and are SVR(can you be Reinfected if your not SVR?) but 4 days before SVR or und, you had a 'big enough viral load' that some virions got on your toothbrush, and now 4 days latter you are und or svr, and those little buggers on your toothbrush are still alive, and ready to infect you. Wow those toothbrush virions have impeccable timing, huh? Oh ya, also your gums were bleeding enough to get the virus on the toothbrush 4 days earlier, and bleeding bad enough now, 4 days latter to let virions enter your blood stream... ?
Remember HCV virus cannot replicate till it hits the liver, no replication on the toothbrush, or your mouth, or your bloodstream.
So those toothbrush virions have to make it past your first line mucous membrane immune system defense(iirr, macrophage), to your blood stream, which is flooded with antivirals and INf, then on to your liver in order to replicate...
hmmm....maybe the plastic in the toothbrush gives these toothbrush virions ''supervironic powers'...lmao
So lets say this far fetched scenario did happen, this very very small group of virions would have to survive the IFN blast that already eradicated them once before when HCV had a firm foothold on your system. Your original HCV infection had thousands or millions of live replicating virirons, and you cleared them with inf. Why would you think these same brand of virions, under the same INF gun,would now be able to take hold?
Very very unlikely, if possible at all.
To think about re-infection this way, is circle thinking imho
apache
UNdetedtible can mean you srill have some few virons on board, or it could mean you have none. We don't know how many are truly free of virus during this time because most tesring goes down only to ..5 or .10....which translates to many thousands of virons still in ones body possibly. The only test which tells the tale accurately is seldom used due to expense and accessibilty to it, and insurance opposition.
Ergo, one could become truly virus free early in treatment. No one knows whether they are moping up the few virons left, or whether they are clear and just following protocol.
The only thing we do know for vertain is that the longer one treats while UND the better the odds of SV become, even for late responders they reached similar success stats when treating out.
Ergo one could reasonably assume that the mop up phase goes on for some time, perhaps throughout the treatment or extended treatment.
That said, your point is taken. Yet this doesn't rule out what some system may do differently. For instance early responders....and I'm sure you know of the new predictive tests and findings concerning them. They go UND in very few weeks, do they also carry virus the entire year? No one really knows this. So it is reasonable to assume that some do, and some do not. Their stellar responses having quickly wiped out any detectible virus, they may accually be virus free and just not know it yet.
That's my point.
No one knows at what point those last hangers on are gone, and so why reintroduce ANY back into the system.
Like I said, and this doesn't seem circular to me,,,,I would not knowingly put someone elses toothbrush to work in my mouth that I knew may have 100 HCV or HIV virons on it, and many toothbrushes have far more than that.
If I would not let someone else's virons into my system, then why would I reintroduce my own bacteria???? Either way it presents some risk.
mb
it's always so sad to hear what you endured, but inspiring how brave you are.
However, the one thing that saves most health workers from getting this is not the gloving up, the gloving only helps IF that person has cuts, sores or torn nails on their fingers. We know HCV is not transmitting through uncut skin, or through saliva alone.
The points of entry are cuts, sores, bleeding gums, nasal mucosa and the eye membrane. Those are the only places the viron, small as it is can slip through and gain entry to our bloodstreams. So your sons care didn't expose you.
I did hospice care for a couple years and also know what all that cleaning up is like, but I don't believe thats how i got it. I'm basing when I got it on when I had fever, exaustion and inability to sleep and other symptoms which was soon on the heals of my quart of plasma and never before that.
I also don't think a minute amount of blood in the mouth will always infect, unless that person has cuts or bleeding gums as well, and if the blood makes it past the mouth there are so many lypocytes lining the throat, plus hydrocloric acid in the stomach, so they don't survive and gain entrance through that route, which explains why your daughter never got infected, and why married couples can remain negative while one is infected. The mouth is not the common route of transmission.
The only exception being, introducing virus into an open or bleeding gum, and since many people who brush regually do blled a little...they don't even know this but they do release some blood with each brushing in most cases, so that becomes the one exception. So until someone proves that a pin ***** and a couple dozen virons can not infect, I'm going to assume it can and does because that's what the current science is showing. Science has been wrong plenty and had to later correct itself, but until we know more, I'd rather defer to what has been shown and provem both in the petre dish AND in real life daily health care facilities world wide. Which is, that it does not take much to infect.
So while your family stories in general don't surprise me,
I am surprised the needle accident you had didn't expose you as thats how many health care workers got this. Someone is definitely looking out for you! Yet that doesn't mean that needle accidents don't account for a large number of cases in helth workers, because they do.
mb