Veterinary Technician Practice Exam

Which of the following is NOT classified as a disease-causing agent for zoonotic diseases?

1. Pathogenic bacteria

2. Viruses

3. Parasites

4. Biologics

The correct answer is: Biologics

The correct choice, identifying biologics as not classified as a disease-causing agent for zoonotic diseases, highlights the distinction between disease-causing organisms and therapeutic substances. Biologics are typically products derived from living organisms which are used to prevent, diagnose, or treat diseases; examples include vaccines and monoclonal antibodies. While biologics can indeed play a critical role in managing or preventing diseases, they themselves do not cause diseases. On the other hand, pathogenic bacteria, viruses, and parasites are all organisms that can directly cause diseases, some of which can be transmitted from animals to humans. Zoonotic diseases are those that can be shared between animals and humans, often facilitated by these agents. Therefore, understanding the role of these various categories is key to comprehending how zoonotic transmission occurs, while recognizing that biologics are developed to combat rather than cause disease.