Zoonotic diseases are transmitted between animals and humans and can pose a significant threat to human health. It’s critical for veterinary clinic staff and TVMDL employees to handle animal samples in a way that minimizes the threat of zoonotic transmission.
According to the Centers for Disease Control and Prevention (CDC), zoonotic diseases such as brucellosis, Q-fever, anthrax, and plague are caused by organisms that are considered bioterrorism agents due to the threats they pose to public health. Other zoonotic diseases such as salmonellosis, rabies, and leptospirosis are not considered bioterrorism threats, however they are still commonly encountered in veterinary medicine and should be handled with the same precautions.
TVMDL has compiled the best practices to ensure clinic and lab staff minimize exposure to infectious agents when handling samples suspected of zoonotic disease.
Protecting yourself at the veterinary clinic
It is crucial veterinary staff receive a thorough clinical history for each patient, which can help determine zoonotic status. Certain signs of zoonotic disease like sudden abortion, neurological abnormalities, fever, and vomiting are also common with non-zoonotic threats. As such, it’s important to handle all animal samples using standard biosafety practices. It’s also important to note the clinical history on the TVMDL Submission Form.
While collecting samples, protective measures such as wearing gloves and disposable lab coats mitigate transmission risks by direct contact. However, zoonotic diseases can also be transmitted by aerosol, droplet spray, or ingestion, so additional equipment such as masks and safety goggles may be needed, depending on the circumstances.
Following sample collection, hand washing and surface and instrument disinfection are always advised no matter the animal’s zoonotic status. Keeping a clean, biosafe environment lessens the risk of transmission through indirect contact on fomites, which are objects such as clothes, equipment, and surfaces where zoonotic viruses and bacteria can still survive. It may be necessary to change instruments, clothing, and shoes when disinfection may not be achievable.
Protecting TVMDL staff
Once at TVMDL, specimens suspected of zoonotic disease must be handled with strict biosafety practices to protect laboratory staff. Therefore, it’s imperative clients clearly indicate if specimens are zoonotic suspects while completing the TVMDL Submission Form.
On the current version of the TVMDL Submission Form, there are two locations clients can use to indicate if a specimen is a zoonotic disease suspect. The first is the “zoonotic suspect” check box located under the specimen type and test request table. If there is any suspicion a specimen could be zoonotic, please check this box to ensure it is handled appropriately by lab staff. This check box is not on all previous versions of the Submission Form. Clients are strongly encouraged to download the current version of the Submission Form from the TVMDL website prior to each shipment to ensure the correct version is submitted.
The second location on the TVMDL Submission Form to indicate a zoonotic specimen is in the clinical history section. Completion of the clinical history section is critical to the overall testing process. Here, the client should list all clinical signs exhibited by the patient, and, if known, a patient’s contact with other animals suspected of zoonotic disease, if the patient is located in an area endemic for a certain disease, and any other details TVMDL can use to infer the specimen’s zoonotic status.
If a specimen is suspected of zoonotic disease, please place the TVMDL Submission Form in a separate clear bag and place on top of the Styrofoam shipping container and below the outer cardboard box flaps prior to transit. This practice helps laboratory staff locate the TVMDL Submission Form immediately while minimizing physical contact with the specimen. This practice is advisable for all samples sent to the lab regardless of zoonotic status.
Lastly, TVMDL advises clients ship zoonotic specimens separate from other diagnostic cases to avoid delays in processing non-zoonotic cases.
To reference this information in the lab, download and print the TVMDL zoonotic specimen handling poster.
For more information on testing for zoonotic disease, call the College Station laboratory at 1.888.646.5623 or visit tvmdl.tamu.edu.