So, I have doctor-diagnosed moderate obsessive-compulsive disorder (OCD). Three months ago, I was scratched by a shared tape dispenser at work. From what I understand, Hepatitis B can be transmitted with just a single-digit number of infectious viral particles, and many unnoticed scratches can leave trace amounts of blood on surfaces. Even though only six people use this machine, I’m concerned there might be viruses on it (because the prevalence of Hepatitis B in China is very high). That’s why I planned to get tested after three months to rule it out.
Later, I learned I could first check for vaccine antibodies. I definitely have a record of three doses from birth, but I haven’t had an antibody test since then, and my current HBsAb level is 0.7. When I asked ChatGPT about the window period, it showed me some cases where the window period extended far beyond three months after vaccination, such as a case recorded by the Japanese Red Cross with HBV DNA negative at 5 months, and another where HBsAg only turned positive after 13 months.
I know these are cases of breakthrough infection, but it made me wonder: could non-responders to the vaccine still develop some protection against HBV replication, albeit incomplete protection, which not only leads to eventually contracting Hepatitis B but also significantly affects the duration of the window period?
Afterwards, I saw that the CDC recommends a follow-up for non-responders up to six months. Because of my strong OCD, I further wanted to know if the CDC’s recommendation for a six-month follow-up is based on publicly available observational data regarding the window period for non-responders, but it seems there isn’t any.
As an ordinary person to question official authoritative guidelines in this way, I know it sounds very absurd. But my OCD and the perceived threat to my life make me unable to stop thinking about this issue.
Now, I really want to know: is the officially recommended six-month follow-up for non-responders reliable?
Welcome to the forum and thank you for sharing your story. I’m sorry that you find yourself in such a stressful situation.
To answer some of your questions,
Transmission of Hep B is not likely in the situation you describe. The single digits you mention are from animal models, which do not always correlate with real-world situations. Just to mention, no instance of mother to child transmission (with birth dose vaccination) has been recorded in mothers with a viral load less than 20000 IU/mL, even though there is quite a bit more fluid exchange during birth.
The information about 6 months are from very early experiments during the development of the vaccine - people were exposed to the virus to test if the experimental vaccinations worked (https://jamanetwork.com/journals/jama/fullarticle/337999). In some cases it didn’t work (non-responders), and the people ended up getting Hep B. They found that the people that did get it all developed HBs antigen within 120 days (~4 months). 6 months was chosen as a good final timepoint. I’d be interested in seeing the data around the case report of positivity 13 months after exposure.
These studies would never be carried out now - as we have a highly effective and safe vaccine. As such, we’re not ethically able to answer your question about non-responders to the vaccine that we do have now.
Thank you for your explanation. Because of my OCD, I have recently become very anxious about the lack of long-term data on hepatitis B infections in vaccinated individuals. I understand that such cases are relatively uncommon because the vaccine usually provides very good protection, but this lack of data led me to develop my own hypothesis that incomplete immune protection might prolong the window period.
From a professional perspective, am I perhaps worrying unnecessarily about this?
I agree with everything that Thomas has said here. I also want to add that your low antibodies now don’t necessarily mean that you were a non-responder to the vaccine. If you got the vaccine as an infant, and it has now been several decades since then, you likely had antibodies as a child, and then the levels dropped. Everybody’s antibodies decline when you haven’t been exposed to the virus for years.
If you are working in the medical field, they generally test people to make sure you have antibodies, and the people who don’t are given a booster shot just as an extra precaution. For others, if you have immune memory from getting the vaccine as a child, your body has a head start, and can ramp up production of antibodies rapidly if you’re exposed again. While breakthrough infections can happen, my understanding is that they are very unlikely to become chronic in someone who initially responded to the vaccine.
Thanks for sharing this information. It looks like this is a very special case where the person exposed had immunodeficiencies that prevented a good immune response. In these cases, even very little virus (which could take an extended period to induce a positive HBs result) are able to take hold - in someone with a normal immune system, it is likely that it would have resulted in clearance. The results of this study should not be extended to the circumstances of otherwise healthy individuals exposed to HBV.
If I were in your shoes, this is not something that I would be worried about.