5. Infections from Laboratory animals and Zoonosis

Working with laboratory animals involves certain hazards, especially with primates. Sometimes newly purchased (or collected) animals can carry asymptomatically infectious agents, some common and some exotic, including oncogenic or slow viruses. Animals can transmit infectious agents to workers by scratching, biting, or shedding their fur. Disease can be transmitted by unsafe handling of tissue samples or clinical specimens.

The most frequent accident in animal research procedures is self-inoculation, or inoculation of the worker handling the animal. Clearly, suitable restraining devices will prevent this. Autopsies generate aerosols as the tissues are manipulated and sliced, and autopsy procedures introduce the possibility of accidentally penetrating wounds from a sharp object. Fecal material may contain more than one billion microorganisms per gram!

More then thirty of the approximately 150 zoonotic diseases have been known to be transmitted from animals to laboratory workers. These include: lymphocytic choriomeningitis, Marburg, herpes B encephalitis, hepatitis, rabies, malaria, leptospirosis, tuberculosis, and others. Sometimes, animals sub-clinically carry the infectious agent and there is no way to predict the consequences.

Another aspect is transmission of disease from man to animal, which can cause trouble in maintaining SPF animals, and can distort test results and evaluation.