In public health, what are infectious agents commonly classified as?

Infectious agents are classified primarily as viruses and bacteria because these organisms are the most common types that cause diseases. Viruses, such as the influenza virus or HIV, and bacteria, like Streptococcus pneumoniae or Escherichia coli, are fundamental to understanding infectious diseases in public health. Their characteristics, modes of transmission, and impact on health are crucial for disease prevention and management strategies.

Focusing on other options indicates that environmental pollutants do not directly categorize infectious agents; instead, they encompass chemicals or substances that may harm human health but are not living organisms capable of causing infection. Physical trauma sources refer to events that cause injury rather than diseases caused by infectious agents. Lastly, social determinants of health relate to conditions in which people are born, grow, live, work, and age, influencing health outcomes in a different context, rather than classifying biological agents. Hence, the classification of infectious agents as viruses and bacteria is foundational to understanding and addressing public health challenges.