What are the post-exposure prophylaxis (PEP) guidelines for someone who has been spat in the mouth, considering potential transmission of infectious diseases such as Human Immunodeficiency Virus (HIV), hepatitis B, and hepatitis C?

Post-Exposure Management for Saliva Exposure to Mouth

For someone who has been spat in the mouth, HIV post-exposure prophylaxis (PEP) is generally NOT warranted, as saliva exposure to mucous membranes poses negligible HIV transmission risk, but immediate flushing with water is essential and hepatitis B status should be assessed. 1

Immediate Actions

Flush the mouth thoroughly with water immediately – this is the single most critical first step for any mucous membrane exposure. 1 Do not use caustic agents like bleach or inject antiseptics, as these are not recommended and provide no additional benefit. 1

Document the following details immediately: 1

• Date and time of exposure
• Estimated volume of saliva and duration of contact
• Any visible blood in the saliva (critical distinction)
• Source person information if known

Risk Assessment by Pathogen

HIV Risk

HIV PEP is NOT indicated for saliva exposure to mucous membranes. 1 The CDC explicitly states that HIV PEP is not warranted for mucous membrane exposure to saliva, even from a known HIV-positive source, because saliva does not contain sufficient viral load to transmit HIV. 1

Exception: PEP might be considered ONLY if the saliva contained visible blood AND the source is known or highly likely to be HIV-positive. 1 In this rare scenario, initiate PEP within 72 hours (ideally within 1 hour) using a 28-day course of combination antiretroviral therapy. 1, 2

Hepatitis B Risk

Assess your hepatitis B vaccination status immediately. 3

• If you are fully vaccinated with documented antibody response: No action needed. 4
• If you are unvaccinated or incompletely vaccinated AND the source is HBsAg-positive or unknown: Administer hepatitis B immune globulin (HBIG) within 24 hours (can extend to 7 days) and begin the hepatitis B vaccine series. 3, 4

Hepatitis C Risk

No post-exposure prophylaxis exists for hepatitis C. 1 Exposure of mucous membranes to saliva from a source with unknown HCV status poses minimal risk and generally does not require further action. 1

Testing may be considered only if the source is known or highly likely to be HCV-positive: 1

• Baseline anti-HCV and ALT within 7-14 days
• Follow-up anti-HCV and ALT at 4-6 months
• HCV RNA at 4-6 weeks if earlier diagnosis desired

Critical Distinction: Saliva vs. Blood

The management changes dramatically if the saliva contained visible blood: 1

• Pure saliva: Not considered potentially infectious for bloodborne pathogens. 3
• Saliva with visible blood: Treat as blood exposure requiring full evaluation for HIV, HBV, and HCV. 1

Common Pitfalls to Avoid

Do not overtreat: The most common error is initiating HIV PEP for pure saliva exposure, which exposes the patient to unnecessary medication side effects without benefit. 1 Saliva is specifically excluded from the list of potentially infectious fluids (blood, semen, vaginal secretions, cerebrospinal fluid, synovial fluid, pleural fluid, peritoneal fluid, pericardial fluid, and amniotic fluid). 1, 3

Do not delay hepatitis B prophylaxis: If indicated, HBIG should be given within 24 hours for maximum effectiveness. 3

Do not assume all exposures are equal: Human bites that result in blood exposure require different management than simple saliva contact. 1

Source Patient Evaluation

If the source person can be identified and is willing: 1

• Test for HIV antibody, HBsAg, and anti-HCV as soon as possible
• Use rapid HIV testing if available to expedite decision-making 2
• This information guides whether any prophylaxis is needed

Follow-Up

For pure saliva exposure with no visible blood: No routine follow-up testing is required. 1

If blood was present or prophylaxis was given: Follow standard bloodborne pathogen exposure protocols with testing at baseline, 6 weeks, 3 months, and 6 months. 2, 3