From the Guidelines
Human bites do not automatically require blood borne pathogen exposure labs, including tests for HIV, hepatitis B, and hepatitis C, unless there are specific risk factors present, such as significant blood exposure or a known blood-borne infection in the biter. The primary concern with human bites is bacterial infection rather than blood-borne pathogens, so proper wound cleaning, tetanus prophylaxis, and possibly antibiotics like amoxicillin-clavulanate are more standard interventions 1. Testing is generally recommended only if the biter is known to have a blood-borne infection, if there was significant blood exposure during the bite, or if the bite broke the skin deeply. For most superficial human bites, routine testing is unnecessary. However, if testing is deemed appropriate, baseline tests should be conducted soon after exposure, with follow-up testing at appropriate intervals (typically 6 weeks, 3 months, and 6 months post-exposure) 1. The risk of disease transmission through bites is relatively low because saliva contains less virus than blood, and the exposure is typically brief, but each case should be evaluated individually based on the severity of the bite and known risk factors of the biter. Key considerations include:
- The severity of the bite and potential for blood exposure
- The known risk factors of the biter, such as a history of blood-borne infections
- The need for proper wound cleaning and tetanus prophylaxis to prevent bacterial infection
- The potential for post-exposure prophylaxis (PEP) if blood exposure occurred 1.
From the FDA Drug Label
For greatest effectiveness, passive prophylaxis with Hepatitis B Immune Globulin (Human) should be given as soon as possible after exposure (its value beyond 7 days of exposure is unclear). Table 1 summarizes prophylaxis for percutaneous (needlestick or bite), ocular, or mucous-membrane exposure to blood according to the source of exposure and vaccination status of the exposed person
A human bite may require blood borne pathogen exposure labs, including tests for Hepatitis B, if the source of the bite is HBsAg-positive. The decision to perform these labs depends on the vaccination status of the exposed person and the source of exposure.
- If the exposed person is unvaccinated and the source is HBsAg-positive, then Hepatitis B Immune Globulin (Human) and HB Vaccine series may be indicated.
- If the exposed person is vaccinated but has inadequate antibody, then Hepatitis B Immune Globulin (Human) and HB Vaccine booster dose may be indicated. However, the provided drug label does not explicitly address the need for labs for HIV and hepatitis C in the context of a human bite. 2
From the Research
Human Bites and Blood Borne Pathogen Exposure Labs
- Human bites may transmit bloodborne pathogens, including Human Immunodeficiency Virus (HIV), hepatitis B, and hepatitis C, by exposing the biter's oral mucosa to the bitee's blood and the bite wound to biter's saliva 3.
- The risk of transmission of these pathogens is considered rare, but postexposure follow-up is still necessary to ensure the safety of both the biter and the bitee.
Testing Requirements
- All biters and bitees require hepatitis B follow-up, as hepatitis B virus can be transmitted by mucosal exposure to blood and, rarely, also by nonintact skin exposure to blood-free saliva 3.
- Biters need HIV and hepatitis C testing only after bloody saliva bites, as the risk of transmission from biter to bitee is negligible without visible blood exposure 3.
- All bitees should be tested for HIV and hepatitis C infectivity, as the biter's oral mucosa invariably gets exposed to the bitee's blood (reverse exposure) 3.
Management of Human Bites
- Human bites should be considered dangerous injuries with potentially serious complications, and management consists of history and examination, wound care, surgical intervention if necessary, assessment of risk of disease transmission, and appropriate antibiotic prophylaxis or treatment 4, 5, 6.
- Post-exposure prophylaxis (PEP) can be a secondary measure to prevent infection by HIV when primary prevention has failed, and is advised for people with sporadic and exceptional risk exposure to HIV 7.