Hi everyone,
I hope you are all having a good week 
I have a quick and silly question regarding Hep B and Hep D coinfection. To be chronically infected with Hep B, do we need to be screened for Hep D also? And how do we prevent being infected with Hep D? I know Hep D is blood to blood transmission, so if we are not already infected with Hep D, does it mean we are safe as long as we do not have any blood contact with anyone who has Hep D? Thank you!
Best,
Tran.
Hi @Tran-ng,
This is not a silly question at all, so much so that I have made this a separate thread because I think it deserves its own discussion.
If you are Hep B positive, it is usually a good idea to at least be tested for Hep D. There has been a bit of resistance to testing for hep D because there had not been any specific treatment for it. This is changing though: Myrcludex B/bulevertide/hepcludex has been approved in Europe as treatment for HDV infection.
Hep D is spread by the same means as Hep B (blood and other bodily fluids), so you would prevent it the same way (not sharing razors, needles, toothbrushes, protection during sex, etc). So what you’re suggesting is correct that we’re safe as long as we watch that.
Hope this helps,
Thomas
Hi Tran-ng,
I’ll chime in with a bit of biology.
HDV is something called a “satellite virus”. It is a defective virus-like agent that is dependent on HBV for transmission between cells and between people. This is because it does not make its own proteins that are needed for moving between cells. Instead, it steals the HBsAg proteins from HBV to make its own outside layer, and the HBsAgs do the work of getting HDV out of cells and into the next cell. It is a really interesting virus from a scientific point of view, with its closest relatives being found in plants (in fact, its very tiny RNA genome can replicate in potato cells if we use molecular techniques to get it into the cells!).
Medically, all HDV patients are also HBV patients, but not all HBV patients are infected with HDV. I fully agree with Thomas that HBV patients should be screened for HDV. Prevention of HDV infection is the same as preventing HBV infection. As HDV uses the HBsAgs to move between cells and people, vaccinating against HBV stops HDV transmission (but this does not work after a person already has HBV). Other methods that impede HBV spread, such as avoiding direct blood contact and using safe sexual practices, also help reduce the risk of HDV transmission. Finally, there is a newly approved drug that is available in Europe and Russia, and is being tested in the USA, that can stop HDV entry in cells. It used to be called Myrcludex B, but is now called Hepcludex or bulevirtide. Finally, a number of other drugs are in development or clinical trials to help stop HDV.
I hope this helps.
John
That sucks. So how did it form. If you can only get hepatitis d if you have hepatitis b, the origination of hepatitis d sounds complex. Is it some viral infection that turns into hepatitis d? Do non hepatitis b carriers get hepatitis d and is acute and then gets spread to hepatitis b carriers?
Hi @NeptuneJ,
Great questions with complicated answers - some we don’t know yet.
We don’t know much about where HDV originally came from or how it got into humans. There are recent studies finding viruses very similar to HDV in all sort of other species (e.g. snakes, toads, newts, birds, bats, rats, deers, and even termites) but these infections occur without Hep B. We interpret this as HDV using other viruses as helpers for it to hitch a ride to the next host. There have been recent data showing that HDV can also use hep C and other viruses to help them spread.
We don’t know why HDV uses hep B for spread in humans, but there are several possibilities:
The research on this is ongoing and super interesting (but also not well-funded, so progress is somewhat slow).
Hope this makes things a bit clearer,
Thomas
As always Thanks Thomas! Hope we all never get it
Are there any increased health risks with HDV that we know of yet?
Does it use the same measurements of core anti-HBc, HBsAg, ALT mentioned on the EXPLAINER: Lab results and their interpretation?
If you have a co-infection with HDV, then you are about twice to three-times as likely to progress to liver cancer or cirrhosis (compared to if you had only HBV).
You would monitor the HBV the same way, but you would add on some HDV assays (for example HDV antigen for diagnosis, and HDV RNA to measure virus levels).
Thomas
Thank you so much Thomas and John for your informative responses! 
What are the chances of being co infected? What are the chances as a whole of getting hepatitis D? Wonder how many people who died of liver cancer or liver failure from hepatitis B also had hepatitis d and never discovered by doctors and patients.
Going to get doctors tomorrow. It’s almost like I don’t even want to ask about getting screened for it bc it might just be better not knowing. If I get tested and find out I have hep d as well as hep b, it might cause more harm than good since there is no treatment or cure for hepatitis d
This is just another blow for hep b carriers. Imo
Echo this Thank you @ThomasTu @john.tavis
Dear Tran-ng,
Sorry to make you a bit uncomfortable. After being a med school professor for 27 years, discussing sensitive topics in straight-forward terms has become second nature to me. I’ll try to be a bit more careful in the future.
John.
Dear NeptuneJ,
HDV can either infect a person at the same time s/he contracts HBV if the source of the transmission was HDV+, or it can “super-infect” during a second exposure of an HBV+ positive person to second “donor” (nerd-speak for the person from whom a viral infection was acquired) who is HBV+/HDV+. HDV can be fairly infectious because it can be at very high levels in some people’s bodies. The risk of becoming HDV+ depends on the frequency of it in the community where a person is. A good reference is the US CDC site on HDV What is Hepatitis D - FAQ | CDC. An HDV endimicity map (ie, a map showing where HDV is most commonly found) is at: Hepatitis D epidemiology and demographics - wikidoc. Even in highly endemic regions, only a minority of HDV+ folks have HDV, but HDV is even more under-diagnosed than HBV is, so our data have substantial limitations.
Note that actions that block HBV infection also block HDV infection, so thankfully people are not defenseless! See my above post for details.
Your feeling that many people who have died from HBV liver cancer may also have had HDV is right. HDV is badly under-diagnosed, and it makes HBV disease worse, including liver cancer. Fortunately, drugs for HDV are becoming available (see my post above).
Hope this helps.
John.
Hi Professor Tavis,
You didn’t make me feel uncomfortable at all. In fact, I really appreciate your response with helpful information! 
Hi everyone,
If I have resolved Hep B infection (HBsAG negative, anti-HBs positive, anti-HBc positive) am I still at risk of contracting Hep D? As far as I’ve read Hep D needs HBsAG for replication…
Kind regards,
Hi Mihab
Congrats. We’re on on antiviral therapy or it HBAsg were negative by own? Could you pls provide some details?
Hello,
HBsAG negative by natural infection I guess, as this was the first time I got tested for Hep B. In the meantime I tested for Hep D test (total anti-bodies) and the result was negative ( < 0.1 AU/mL, CLIA method).
Starting with the beginning of December I had some oscilating GI tract symtoms ( abdominal fullness, early satiety, bloating, nausea), and I still have.
After 2 months of investigations with no negative results (colonoscopy, superior endoscopy, abdominal echography) I got tested for hep and this were the results.
Now my main concern is if I contracted Hep B recently (within this two months) or it was a past infection…
Best regards,
Hi @mihaiB,
If you were anti-HBs positive (>10 mIU/mL) before 2 month ago, then it is not likely that the symptoms are due to HBV infection.
Thomas
Hi, all. Hope everyone is well. How does the HDV come about in an infection? Is it treatable? How transmittable is it to those vaccinated for HBV? Can someone with a chronic HBV infection be infected by HDV?