Inactivating Hep B

Hi Drew,

We routinely remove the envelope of HBV (that kills it) with a detergent solution that is milder than typically used for dishwashing (for example, 0.5% NP40 on ice for 10 min), so a really good washing in hot water, making sure to get into any cracks or indentations on the pots, knives, and cutting board will do it. Make sure the surfaces are in contact with the hot soapy water for a few minutes or longer. If you want to get more aggressive, wetting the contaminated surface with a 10% solution of household bleach (ie, 10 ml bleach + 90 ml water) will also efficiently kill the virus (that is the method required in my lab by the local safety authorities). I don’t have any experience killing HBV with heat other than using an autoclave (they sterilize with hot, pressurized steam at ~120C), but I would be very surprised if the virus survived baking at 175-200 C for 0.5-1.0 hours.

I also want to commend you for your concern about transmitting the virus. That shows an honorable concern for others.

John.

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Well, I think these procedures are ok but if the have been vaccinated and if they responded to vaccination (anti-HBs titers > 10 IU/ml) they are protected anyway

Prof. Pietro Lampertico, MD, PhD

Full Professor of Gastroenterology

Head of Gastroenterology and Hepatology Division

Fondazione IRCCS Ca’ Granda Ospedale Maggiore Policlinico

University of Milan

Via Francesco Sforza 35

20122- Milan

Italy

Phone +390255035432

Fax +390250320410

Email pietro.lampertico@unimi.it

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Thank you Mr. @john.tavis!
And thank you all again for your responses!

I will clean them with ousehold bleach first and then burn them in the oven at 250C for 90 minutes just to make sure… Mr. @availlant mentioned only 15 minutes but I guess there is no harm in overdoing it a bit just to get it out of my mind.

Once again I feel so lucky that this community exists!

All the best,
Drew

Drew just so you aware sterilizing conditions are 121 degC for 30-60 min.

You can do whatever makes you confortable…

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So in that temperature any pathogen dies including HBV? Thank you for letting me know!

Hi @Drew_rous,

I agree with the points that Prof Lampertico, Dr. Vaillant, and Prof Tavis have made here. While there is a lot that captures our attention about how transmissible Hepatitis B is, we also underestimate just how effective something like warm soapy water is to inactivating viruses. Just because our hands and skin tolerate them fine, doesn’t mean they can’t kill viruses.

That in addition to your very low virus levels and vaccinated family make the risk of transmission almost negligible. Honestly, the risk of being hit by a car while crossing the street or driving is probably much higher than passing the virus on in this way.

Hope this puts the risk into perspective.

Yours sincerely,
Thomas

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Correct Drew_rous!

I echo Thomas’ comments…

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This is such an interesting conversation and highlights the great concern that those of us living with hepatitis B have about transmission. While the vaccines are such an important part of solving the problem, we know that there are many people that slip through the cracks. Even in the US, we are seeing a surprising number of acute HBV in people who should’ve been vaccinated based on their age. So we shouldn’t ignore the population pool of viremia that exists in those of us living with HBV.

I want to bring up an issue that I feel like is not addressed much and yet is something as a woman I think about often. Women menstruate monthly and it’s a lot more blood than what we are talking about thatn with the scrapes/scratches/tooth brushing/razors which are often discussed when we talk about exposure. While we hope there isn’t a lot of contact with others with our blood, I’m not sure that we’ve identified or addressed the risk.
What is the risk you might be wondering? I think of people who may be sexually active maybe at the beginning or end of their cycle when there is still blood that may not be visible or how about with disposal of menstrual products (tampons, pads) where there might be some exposure (it wouldn’t be like with needlestick injuries), but is there any risk here?
I know this is not a topic people enjoy talking about, but I haven’t seen any studies on this and would be good to know what the science is.

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With hand washing, if one has a cut on the hand and is an open wound, I get that soap is not going to do kill the virus until it’s covered up, but what about getting hepatitis b infected blood on your hands(let’s say), could soap and running water wash it off? Leaving no risk on the washed hands or does the virus attach itself to the skin or can soap and running water not wash it off.

I read hepatitis b virus can survive and be infectious for a week outside of the human body. Maybe just on countertop or whatever. But could it be washed off. Not killed but washed off so there are no traces of it

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Being an enveloped (lipid surface) virus, it is easily killed by a handwash/Detergent within seconds

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hello!
I have a question not only about HBV but viruses in general.
I am going to study in Germany next semester and I currently looking for an apartment. Most of student apartments in good spots, that is city center, do not have a washing machine as they are tiny. Instead tenants wash their clothes in communal washing machines in the basement.

Firstly, it is my understanding that with the exception of a very big visible blood spill on clothes using thoses machines is safe for others despite my HBV+ status (btw my load is 218 iu/ml and HBsAg 16,97 if that’s relevant), right?? Secondly, is it safe for me? Is sharing a washing machine completely safe when so many people use it with whatever that entails?

Best,
Drew

Dear @Suwang88,

What a great question and, to my disappointment, there hasn’t been any research into viral loads present in menstrual fluids that I can find. This may be part of a wider symptom of biased scientific research that mostly has focused on problems experienced by males because the opportunities for women in research had been so limited. While this is starting to change, we are not close to equality yet.

I think we just assume there is risk, but I’m not sure where that data is that shows it. Perhaps other @ScienceExperts might be able to find some?

Hi @NeptuneJ, if you wash it off with soapy water, then the soap will kill it within seconds as @ASK pointed out.

Dear @Drew_rous,

As mentioned earlier in this thread, machine washing with detergents will kill most (if not all) viruses, including Hep B. This should be safe and there doesn’t appear to be any reports of communal washing laundries to be linked to outbreaks of disease. If it was, then I would think that hotels everyhwere would definitely be in some trouble.

Cheers,
Thomas

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Hi @Suwang88,

Tim Block linked me up with some early studies about HBV presence in various fluids and suggested since blood is a major component of menstrual fluid that it probably reflects the same risk of transmission. Probably the strongest evidence is the following article (in full below) in the lancet from the mid-70s.
HBV in vaginal secretions

None of these studies seems to have shown PCR confirmation though.

TT

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Hello Dr Thomas : Why don’t you take up this in your lab?

Good question! While there is this perception that scientists just experiment by throwing stuff together based on what they’ve just come up with, this does not extend to experiments involving humans or tissues from humans. There we are under very strict guidelines to need to justify our research, make sure we do absolutely no harm to patients (or if we do, that it is very much outweighed by the benefits), and that the participants know what they are getting into. It is a multi-month long process to get approval for these studies and sometimes even longer to start enrolling people into the study. Meanwhile, I have many other projects that need doing.

It’s not that this isn’t important to know, it’s just that it is very difficult to start. I have the assays to look at HBV DNA, it’s getting the sample in an ethical way that is the issue. If there are scientists that have biobanks that could be used for this purpose, that would be an easier way around it, but I’m not sure of anyone who does.

TT

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Hello everyone!
I have one silly question. Having a wisdom tooth removed a few days ago has resulted in a minor wound for a few days. I was brushing my teeth today and I started wondering. Does toothpaste kills hbv?

Thank you very much!

Best regards,
Drew

Hi @Drew_rous,

Interesting question. Toothpaste does contain surfactants (e.g. SLS), which could have potential anti-microbial activity against HBV. It all depends on the concentration really, which might be variable around the mouth. My gut feeling is that I would not depend on it for killing HBV.

Thomas

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Hello @ThomasTu,
Thank you for the answer. I was just curiousabout the best course of action for inactivating HBV after a dental procedure since there might be a considerable amount of blood in mouth for a few days.
First of all, must there be a procedure? Is there any risk from remaning HBV in mouth days after the procedure when the injury has been healed? In other words, after the injury heals, soes HBV still resides in mouth?

Best,
Drew

Hi Drew_Rous,

This was an interesting question. Certainly HBV remains stable in saliva and has been postulated to be a vector for transmission although again this would required an open wound coming into contact with infected saliva. Salivary transmission of HBV does not occur by kissing, sharing utensils or breastfeeding.

Certain mouthwashes containing chlorhexidine gluconate do have effective virucidal activity against HBV. https://journals.sagepub.com/doi/10.1177/00220345900690030901.

Cheers,

Great questions and I don’t think any of these questions have been well answered by the scientific community. From what we know about hep B, there is potential risk, but as far as I know, there hasn’t been any cases reported of transmission through this route (though there is through dental equipment, I believe). This highlights the importance for everyone to be vaccinated to protect themselves.

TT