Infection prevention and control guidelines

8. Exposure to blood and other body substances

Blood-borne viral infection risk

      1. Blood-borne viral infection risk

Last revised: 17 Jun 2024

Blood-borne viral infection risk

Exposure to blood and other body substances is a risk for transmission of blood-borne viral infections such as hepatitis B, hepatitis C or HIV between healthcare workers and patients.

Procedures associated with risk of exposure of blood-borne viral infections include management of traumatic injury and invasive procedures where there is potential for direct contact between the skin (usually finger or thumb of the healthcare worker) and sharp surgical instruments, needles, or body parts (such as fractured bones or teeth). The degree of risk depends on the amount of blood or body substance injected and the viral load of the person whose blood or body substances were involved in the incident (the source).

The risk of transmitting a blood-borne virus from an untreated infected healthcare worker to a patient during an episode of exposure varies between studies and has been reported as 0.2–13.19% for hepatitis B virus, 0.04–4.35% for hepatitis C virus, and 0.0000024–0.000024% for HIV. The risk of transmission from an untreated infected patient to a healthcare worker during an exposure episode has been reported as 1– 62% for hepatitis B, 0–7% for hepatitis C, and 0.3% for HIV infection.1

All blood and body substances must be treated as though infectious, regardless of the person’s diagnosis or perceived risk of transmitting infection. Blood carries the highest risk (see Assessing risk of infection transmission).