Hello all. I apologize in advance, because I have awful contamination OCD, so forgive me if this question seems silly, but it’s been eating away at me.
I work in retail, and yesterday evening I handled a transaction from an older man with many dried bloody cuts all over his hands. He gave me money and I also had to hand him a receipt, and he touched my hand both times, as much as I tried to avoid it. I wear gloves at work for this precise reason, but I wasn’t able to replace my gloves since I had to stay at my register the entire shift. I did handle many other customers in this time period, but towards the end of the night, I forgot that I had touched that man’s hand, and accidentally rubbed an itch on the nape of my neck where my hair begins.
My question is, if I didn’t shower or wash the area I touched on my neck, is there any transmission risk of HBV or HCV to myself? If I toss and turn and manage to have my eyes/mouth touch areas of my pillow that the area of my neck had touched? If I shower and wash my hair, can I risk having it travel to vulnerable areas of my body through the water? This has been eating at me all day.
Thank you in advance for anyone’s advice
I will note that although my gloves were black, I did not see any dried blood transfer to my hand, but I am aware of there still being presence of the virus despite that.
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Hi @just_asking,
There’s negligible risk of transmission through the routes that you have described. It is similar to the questions we’ve had in the past about 2nd and 3rd hand contact and not even being sure that there’s any virus present at all.
Hope these help,
Thomas
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I want to second Thomas’ comments. The risk of transmission is negligible. Please set your mind at rest.
John.
Thank you, @ThomasTu and @john.tavis ! Am I to understand that the only real risk would be directly touching dried blood, and not from transference of any dried blood I had touched to other surfaces or areas of my body? If his dried blood were to touch my clothing, and my clothing were to touch my cuts, or my washing machine, etc., etc., would that still be no cause for concern?
I am sorry for my ridiculous questions but this has been an ongoing fear of mine for some time
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HI @just_asking
No question is ridiculous if you don’t know the answer and don’t have the information to reason it out!
HBV transmission requires direct contact of an infectious sample with an open sore on the recipient. The “open sore” need not be very large–just anything that brings the recipient’s blood into direct contact with the sample. Cuts or micro-ruptures in skin or the oral, genital, or anal mucosa can provide an entry route. Dried blood can still have active HBV in it, so it should be treated as a biohazard. However, HBV cannot burrow through intact skin and has a very hard time crossing intact mucosal barriers. Also note that the likelihood of transmission is proportional to some degree to the amount of HBV in a sample, and as the amount of HBV in an infected person’s blood can vary by 10 million-fold or more, not all people are equally capable of transmitting the virus.
That being said, even people with low levels of HBV can transmit the virus under some circumstances, so caution is always a good idea. Preventive measures include getting yourself and your intimate partners vaccinated, not sharing injection needles, not sharing grooming and hygiene items such toothbrushes or combs, using a condom during sex if the non-infected partner has not been tested and found to have a high enough level of anti-HBV antibodies, and limiting risky sex activities. If a suspected exposure occurs to an unvaccinated person, wash the infected site with soap and water as soon as possible (regular household soaps will kill HBV), and if the risk of transmission is substantial (like someone in a physician’s office getting a needle-stick), immediately seek medical help because getting injections with HBIG (purified anti-HBV antibodies) plus vaccination right away can stop an infection from occurring.
Washing contaminated clothes with a regular household detergent will efficiently kill HBV through a combination of heat, soap that destroys the viral membrane, and enzymes in most commercial detergents that degrade the virus. To clean an infected blood spill, put on non-absorptive gloves, cover the blood with a paper towel soaked in a 10% solution of household bleach (for example, 1 mL of bleach + 9 mL of water) and let it sit for 30 min. Then wipe up the mess and wash the surface with a soap solution.
I hope this helps.
John.
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Thank you very much, @john.tavis , your information is helping to put me at ease. One final question, if you don’t mind me asking: does vaccination help prevent contracting the virus, even in situations where you have a cut touching dried blood with potentially high viral loads? I have seen vaccination efficacy ranging from 90-95%, and would like to know if viral load affects possibility of infection even if fully vaccinated, or if the vaccine provides blanket protection even to that kind of exposure?
Hi @just_asking,
I’m pleased I could help.
The 90-95% efficacy number for the HBV vaccination refers to the proportion of people vaccinated that develop high enough antibody levels to block HBV infection. The vaccine is among the best medical science has ever made, but some people do not generate enough antibody from it for full protection (that is true for almost all vaccines). I’m one of the non-responders–I’ve been vaccinated with the full series twice and never developed measurable antibody levels against HBV. So basically if a person is in the 90-95% majority of people who respond to the vaccine, then they are immune to HBV as long as their antibody levels remain high enough.
John.
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Thank you @john.tavis !! I know the CDC doesn’t recommend boosters for this particular vaccine, so does that generally mean that most people should have sufficient HBV antibodies from completing the full vaccine series, for life (or at least, the better part of it)? Since many sources also mention that it wanes over a period of 20-30 years
Hi @justasking
Immunity to the HBV vaccine wanes as people get older, just like most types of immunity. The rate of decay varies greatly among people, and their peak levels of immunity can also vary by a lot, so it is very hard to predict when someone might drop below the 10 mIU/ml concentration of anti-HBs antibodies that is often considered the amount needed for immunity. There are some data from a study with nursing students in Taiwan where universal birth dose vaccination was first introduced indicating that in a minority of these students, mostly young women, that immunity had dropped far enough for traces of infection to be detectable. To my knowledge (and I may not be up to date), the data are not yet clear enough for the major medical advisory groups to recommend a booster dose. We have some excellent vaccinologists here at Saint Louis University who I’ve asked about this, and they mostly think a booster will eventually be recommended, but that significantly stronger data will be needed to justify a recommendation change. For now the practice in most places is that you get your anti-HBs antibody levels tested if you are concerned, and get a booster shot if they are low.
For what it is worth, my wife and I had our 2 sons vaccinated at birth and then had them get a booster dose when they were 18 and entering college.
John.
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Thank you very much for the insight, @john.tavis , it has been very helpful!! 