Which of the following is a common blood borne pathogen?

Hepatitis B is recognized as a common blood borne pathogen because it is primarily transmitted through contact with infected bodily fluids, particularly blood. This virus can lead to serious liver conditions, including chronic hepatitis, cirrhosis, and liver cancer. Understanding Hepatitis B's transmission is crucial in sports medicine practice, as professionals must implement proper precautions to prevent infection, especially in situations where blood exposure is possible (e.g., injuries, blood spills).

In contrast, the other options do not primarily spread through blood. Hepatitis A, while a viral liver infection, is primarily transmitted through ingestion of contaminated food and water rather than blood. Influenza is a respiratory virus spread primarily through droplets when an infected person coughs or sneezes, and Lyme disease is caused by a tick bite, involving a different transmission pathway altogether. Therefore, Hepatitis B stands out as the common blood borne pathogen in this context.