Constant fear of transmitting the virus

Dear Sir,

I am a chronic hep B patient with 29 iu/ml of hbsAg and 1,143 iu/ml viral load.

This is the scenario. Sorry if it sounds sensitive: Let’s say, I have a healing canker sore near my tonsil (white in the middle and little bit red around it) and then there’s a small amount of blood mixed with the spitted toothpaste (probably from the small holes in the tonsils) after brushing my teeth.

Is it possible for me to transmit the virus through deep kissing or blow job after brushing my teeth?

Thank you, sir.

Hi @Nannyplum,

Welcome to the forum and thanks for your question. If you don’t have an obvious break in your skin, then the risk of transmission (even if the mother was highly positive) is quite low. If you have been vaccinated (which is best practice for all health care workers) and you have protective levels of antibody, the chance that this becomes a chronic infection is negligible.

Dear @Jodie_2nd, welcome to the forum and thanks for your question. If there is blood in your saliva and a break in the skin of your sexual partner, then there is a chance for transmission.

Hope this helps,

Hello again @ThomasTu

Thank you for your answer sir, it made me scared even more, I just found out that my antibodies are low, just 5.74mIU, but in worst case scenario, that I have open wound in my hand,was there a high chance of transmitting HEPA b with that kind of scenario ( putting clothes on a baby, without visible blood on her body )

Thank you!

Dear @Nannyplum,

I cannot give you probabilities given so many unknown variables (whether or not the mother was positive, if they were positive how high their viral load was, how you actually handled the baby, if there were inadvertent scratches or blood). However, as far as I understand, there is little risk for HBV infection from exposure to intact skin.

If you are worried about it, it would be appropriate to consult with a specialist about appropriate post-exposure procedures (which may include a booster vaccination and HBIg).


@ThomasTu Thank you, sir, for your response. Follow-up question, if there’s a chance of transmission, does it mean that it will be infectious?

Thank you, again, sir.

Thank you so much for your response!

Sorry if I sounds so desperate, but will it be possible that the HBV stays in the surface of the baby’s skin ( even without visible blood ) and transmit it to me if I have NON bleeding and old scratches ( those scratches that won’t hurt even you put alcohol on it ) on my hands?

Thank you again for your very informative response sir.

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If a person is exposed as an adult, there is ~90% chance that they would fight it off (even without being vaccinated). The risk of a chronic infection is low.

This to me doesn’t sound like an open wound. If this is correct, the risk is very low. However, please note that there are few scientific studies on this and it is difficult to provide solid numbers for risk evaluation.


Thank you so much for your response sir!


@ThomasTu Thanks for replying Dr Thomas
I have another question, my brother who worked on vascular surgery the patient had positive hbv and the field is bloody and I think there may be some blood toched my brother clogs while operating he put the clogs in glove and put it in his bag after that my mother took the clogs out of the bag and put it on the floor where it was resting on my bag will touching my bag will be infectious if the clog didn’t contain liquid blood there may be some traces wich changed the color and dried that’s why my mother thought the clog was clean

Dear @Mohammed_Yassin,

I think if there is such risk of coming into contact with blood, everyone involved should try to be vaccinated just in case of exposure. It is difficult to know exactly what the risk is given the big number of variables (how much blood, how high the viral load of the other person, the vaccination status of everyone, whether the outside of the gloves were clean, etc.).


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okay thanks
we will get vaccinated but the question is does dried blood infect other surface I mean if I have 2 object A with dried blood and B without any blood if B was with close contact with A will be also be infectious?
also I have one shot of vaccine 6 months ago but due to travel reason couldn’t continue to complete my 2nd and third dose I will continue vaccination but will this one dose provide immunity for that short duration (6 months)?

How true is this? He claim he works at hep b helpline UK.
@ThomasTu @availlant @john.tavis @HealthExperts

Hello everyone!

I had another incident and I would appreciate your input.
My family is visiting and my niece which is 21 months old saw a juice box I was drinking and tried to drink using the straw. I managed to take it away from her before starting drinking but I think the straw touched the inside of her mouth. She is fully vaccinated with 4 shots but I had a dental procedure a few days ago and still haven’t recovered from it (there are some sores on my gums). Her pediatrician said that there is nothing to worry about given the possible exposure and her vaccination history. (Last time I checked 5 months ago my viral load was 3190 IU/mL.

I am just worried. Is there anything we should do?


Dear @Mohammed_Yassin

HBV can remain infectious on dried surfaces for up to a week, so dried blood is a hazard. The standard health recommendations for cleaning an HBV+ blood spot are: Put on exam gloves and wash the dried blood spot carefully with a strong detergent (a strong toilet cleaning fluid should work) or treat it with 10% volume/volume household bleach (ie, 1 ml bleach + 9 ml water) and let it sit exposed to the cleaning fluid or bleach for ~10 min.

Note that just because dried blood CAN be infectious does not mean it carries the same risk as fresh blood. First, it is a solid and so it is harder to transfer to a cut or other abrasion. Second, infectivity will gradually decline over that period.

Getting vaccinated for HBV is always a great idea!

I hope this helps.



Dear @Drew_rous,

This strikes me as a very low risk event. HBV does not accumulate in saliva to an appreciable extent unless there is a cut or abrasion in the mouth. So unless you had blood in your mouth (you’d taste it–blood has a really strong flavor), there would almost certainly be no virus on the straw. Second, the volume of saliva transferred by a brief tap to the mouth would be negligible. Finally, she’s been vaccinated, so she’d be protected unless she’s one of the rare folks who do not adequately respond to the vaccine.

I hope this helps put your mind to rest.


Hi @ Drew_rous,
Here is the thing, from what I know In other for there to be a transmission the other person must also have a sore or cut for there to be exchange. If none of this exist, then the chances are zero. You might have wound/sore in your mouth, but your niece would also need to have a cut or sore/wound for even that to be possible. Remember, hepatitis B is a blood borne disease and there has to be a blood exchange between you and your niece for any transmission to occur.

The second but equally important thing is that your niece is fully vaccinated. I know you are concerned, but hepatitis b transmissions happen when there is blood exchange between two people. If there is no blood exchange, the chances are probably zero.

This is my thoughts. I hope it helps keep you at ease. Best, bansah1.

Hi @Godsown,

HBV+ blood is highly infectious, so the advice in this text with respect to avoiding blood, not sharing razors or tooth brushes, etc. is good advice.

The relative risk of HBV+ blood vs semen or vaginal fluids depends on a huge number of variables. How high is the HBV level in blood, is there an open wound or lesion on the penis or vagina? How much blood or fluid is transferred? Is it transferred by oral, vaginal, or anal sex, etc? So I’m not comfortable with this blanket statement about sexual transmission. Concentrating on avoiding blood contact is good, but minimizing the risk of sexual transmission is short-sighted. Safer sex practices such as wearing condoms, avoiding sex when a lesion is on the genitals (such as herpesvirus sore), limiting sex partners, avoiding rough sex that could cause a lesion, etc. are good approaches to minimizing risk.

Regardless, getting vaccinated against HBV is always an outstanding strategy!

I hope this helps.


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Dear @john.tavis,

Thank you for your prompt response! I really appeciate taking the time to answer everyone’s question.

Her pediatrician was certain that there is nothing to worry about and it’s allo good but I wanted to check with some HVB specialists.


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If an individual have pimples (The pimple is intact,it has not break yet), An hbv+ blood spill on it can transmission happen in this case?
@john.tavis @ThomasTu @availlant @ScienceExperts