HBV: environmental infection: key questions

Question

Dear Dr Dieterich, I have found myself worrying a lot about HBV infection.

I think the worry comes from the fact that one can be infected from invisible specks of blood which can remain infectious for a week or more, and that so many HBV cases have no identifiable risk factor.

My specific concerns are to do with picking up the virus from dirty public places such as metro trains, escalator handrails and toilet doors and then transferring the virus to my mouth via food or by inadvertent hand to mouth contact. I am also concerned that the virus could be passed from my hand into my pocket and then onto the toothbrush which I sometimes carry there.

It would be great if you could answer the following questions, which I think lie at the heart of many peoples paranoia about this disease. A) Is hand-to-mouth HBV infection from invisible blood specks on public / urban surfaces a genuine risk? B) Can these tiny HBV particles theoretically be transferred from one dry surface to another (EG Hand to Cell phone to Toothbrush to Mouth).

Thanks for your time and this wonderful service - I will be making a donation.

TB.

Answer

Hepatitis B is really transmitted through blood and sex. All those things you describe are virtually no risk activities. Forget them. Get the vaccine! If you get the vaccine, you can't get HBV no matter what the risk. You should get vaccinated for hep A as well, because that is transmitted by food and fecal oral contact. Stop worrying and get vaccines! DTD