Which of the following statements regarding laboratory-acquired infections is not true?

The statement indicating that researchers handling human pathogens have never been infected with an agent as a result of an exposure in the laboratory is not true. In fact, numerous documented cases exist where laboratory personnel have contracted infections from pathogens they were studying. This highlights the inherent risks associated with working in laboratories that handle infectious agents, emphasizing the need for strict adherence to biosafety protocols.

The other statements reflect realities of laboratory safety and exposure risks. For example, it is well-known that most laboratory-acquired infections do have an identified route of exposure, whether that involves direct contact, inhalation, or other means. Proper disposal of biohazard materials is critical, as improper procedures can lead to infections not only for the researchers but also for others who may come into contact with waste products. Furthermore, there is substantial documentation of exposure incidents across various laboratory settings, underscoring the importance of maintaining vigilant safety measures to prevent such occurrences.