Questions and Answers - Transmission

Note: This page is intended for those who need "quick" answers to complex issues. For a more complete story, please refer to the other pages on this site. As I am not a physician, the recommendations I may make are not intended to be used as personal medical advice. I can only urge one, if in doubt, to discuss one's questions with a trained health care provider.

Commonly Asked Questions and their Answers

General | Transmission | Vaccination | Treatments

Is there any indication that the HBV virus can be transmitted to/from domestic (or exotic) animals or pets?
The human hepatitis B virus is only capable of infecting humans and higher primates. As such, domestic animals and pets (with the exception of those mentioned) would not be able to contract or pass on the disease as a human carrier would. However, the virus is able to linger on various surfaces. (See Epidemiology) Surfaces could be anything from countertops to animals' fur or skin. As virtually all bodily fluids of an acutely infected individual can contain the virus, it may be possible to transmit the virus indirectly through casual contact with pets, especially if the pets are exposed to the blood of an infected person. The blood of an infected individual contains the highest titre of the virus.

As an aside, I have not actually read of any studies done on this mode of transmission probably due to its unlikeliness.

Can HBV be transmitted through the saliva?
From my understandin, hepatitis B viral particles can be found in all bodily fluids, including saliva. However, the highest concentrations of viral particles are in the blood. Yet, due to eating, brushing, etc. the saliva of an infected individual may contain some blood (perhaps this is why it can be detected in the saliva). As such, there is a risk, though probably quite low. (See Epidemiology)

How infectious is this disease? Can it be transmitted through general use of same objects by the infected person and non-infected persons?
The Hepatitis B virion is a relatively infectious virus. It can be found within blood and other bodily fluids. It is capable of surviving for over a week, lingering on surfaces. (See Epidemiology) However, the primary route of transmission is through blood contact. This could be anything from cuts to needles, and pin pricks. Even shared razors, toothbrushes, and gorged mosquitoes may harbor the hepatitis B virus, thus increasing the likelihood of transmitting the virus, though the significance of these modes of spread are debatable.

What would make a blood donor who does not use drugs and does not have sexual relations with infected persons, come up positive for hepatitis b antigens?
Though blood transmission and sexual contacts are the most likely route of infection for HBV, they are by no means the only routes. Some studies add the term "household contact" onto the list of possible routes of transmission. Contact with blood, perhaps when dealing with someone with HBV who was cut, can lead to viral transmission. Also, saliva has been reported to carry some hepatitis B virus. One does not need to use intravenous drugs or be involved in sexual activity to contract HBV. (See Epidemiology)

Does this mean they have Hep B?
Most likely, but not necessarily. If a person had been recently vaccinated, the hepatitis B surface antigen may be present in the blood at detectable levels (depending upon the type of assay used to detect them) (See Diagnosis)

If the person has Hep B, what steps should be taken?
The next steps would be to verify the results of the first test. One could also have a physician do blood work looking for the HBe antigen in the blood. If the infected individual shows no symptoms of infection, that person is likely able to clear the virus. Most people with HBV infections manage to fully recover. (Last report quoted about 95% infected recover after mild symptoms.) However, if jaundice or other forms of complications arise, it may become necessary to do a needle biopsy of the liver to examine and verify the extent of liver damage.

If a person had hepatitis a while ago (15 years) and meets someone later, could he/she be still be infected even if he/she had been treated and cured. In other words, is there a cure?
No "cure" for hepatitis B virus per se. However, ~90% of all individuals infected with the virus completely recover and no longer will transmitt the disease. Currently, treatment is only primarily for chronic carriers. While there are some reports of cure, itis not common. Whether or not someone who was previously infected can still transmitt the disease would depend on whether or not they are still producing live virus. This can be checked out by a blood test.

If there has been a blood spill of blood infected with HBV and the spill is cleaned up and disinfected, what is the likelihood that live virus will still be found? If the spill is wiped up, but not properly disinfected, how long would the virus be expected to survive? I recall having previously read about a study where live HBV was found up to six months after a blood spill was cleaned up and disinfected, but now I cannot locate the study, do you have any information?
I have read reports about the hepatitis B virus managing to linger on surfaces for over a week.

Bond, W.W., Favero, M.S., Petersen, N.J., Gravelle, C.R., Ebert, J.W., Maynard, J.E. 1981. Survival of Hepatitis B Virus After Drying and Storage for One Week. Lancet; 1: 550-551.

I guess it really depends on how much virus was left behind and what methods were used to disinfect the area. Many recommend using 0.05% to 0.5% sodium hypochlorite or ammonium germicides and phenolic-based disinfectants to decontaminate affected areas.

It would also be wise to get those who are at higher risk vaccinated against HBV to remove the possibility of contracting the virus.

Is there any disinfectant effective against the virus? If so, what are the active ingredients?
Many cleaners such as bleach and ammonium-based cleaners appear effective at sterilizing surfaces exposed to the virus. I think I cover it briefly in my epidemiology page.

- Copyright © Robert G. 1997-2000 -

General InformationMolecular VirologyOther InformationQuestions & AnswersTerms & JargonRelated Links