Common Safety Orientation (CSO) Practice Test

The principal bloodborne pathogens of concern are primarily hepatitis B virus (HBV) and human immunodeficiency virus (HIV) because these two pathogens are significant threats in occupational health settings due to their potential for transmission through blood and other body fluids.

Hepatitis B virus is a major concern because it can lead to chronic liver disease and has a highly infectious nature; it remains viable outside the body for several days. This means that even small amounts of infected blood can pose a risk for infection. On the other hand, human immunodeficiency virus is known for attacking the immune system, leading to acquired immunodeficiency syndrome (AIDS). While it is less stable outside the body compared to HBV, the risk of transmission through certain exposure events—such as needle sticks or transfusions—means it is crucial to recognize and mitigate these hazards.

The other options present pathogens that do not primarily categorize as bloodborne. For example, while hepatitis C virus (HCV) does pose a risk, it is not as prominent as HBV in many occupational settings. Severe acute respiratory syndrome (SARS) is primarily a respiratory virus, and human papillomavirus (HPV) is typically transmitted through direct skin-to-skin contact rather than blood