Other ‘Superbugs’ Found in Portuguese Veterinary Practices: a Study on Staff MRSA Carriage and Environmental Contamination

Results of a Portuguese study indicate that examination tables, scales and other surfaces in small animal veterinary practices are often contaminated with “multidrug resistant germs”.

The research, which was presented at the European Congress of Clinical Microbiology and Infectious Diseases (ECCMID) in Copenhagen, Denmark (April 15-18), found that 19% of surfaces contained at least one multidrug-resistant bacteria.

Dogs, cats, and other pets are known to contribute to the spread of multidrug-resistant pathogens that can cause human disease. Small animal veterinary practices (SAVPs) are a potentially important link in the spread of these pathogens, and with the increasing numbers of SAVPs in Portugal, it is important to determine the prevalence of multidrug-resistant bacteria in this part of the veterinary sector.

Joana Moreira da Silva and colleagues from the Antibiotic Resistance Laboratory at the Center for Interdisciplinary Research in Animal Health (CIISA) of the Faculty of Veterinary Medicine of the University of Lisbon, Portugal, studied eight SAVPs, all of which were in and around Lisbon.

Critical surfaces, including surgery tables, shear blades, examination tables, and scales, were swabbed, and nasal swabs were obtained from veterinarians, veterinary nurses, and other staff.

The swabs are tested for the presence of multidrug-resistant bacteria.

At least one multidrug-resistant bacteria was found on 18.9% (34/182) of the tested surfaces. These bacteria include Acinetobacter spp. and staphylococci, including S. pseudintermedius. These bacteria are responsible for highly resistant clinical infections in both human and veterinary medicine.

In one veterinary practice, 18.2% of tested surfaces (4/22) were positive for OXA-23 producing Acinetobacter spp. These bacteria, which are found on several different surfaces, are resistant to carbapenem antibiotics. Carbapenems are banned in veterinary medicine by the European Medicines Agency (EMA) and play a vital role in human medicine, forming part of the last line of treatment when other antibiotics have failed.

Together with previous studies finding carbapenem-resistant infections in domestic animals, this highlights the possibility that SAVPs may play a role in the dissemination of multidrug-resistant bacteria in the community.

Methicillin-resistant Staphylococcus aureus (MRSA) was not found on any of the surfaces tested.

Approximately 23% of the workers were carriers of MRSA. While MRSA is not common in veterinary medicine, nasal load is common in human healthcare settings and in the community.

However, if MRSA enters the body, through cuts or catheters, for example, it causes lung, skin, and other infections, some of which can be life-threatening. The bacteria are on the World Health Organization’s list of “priority pathogens” that are resistant to antibiotics – meaning they are among the bacteria considered to pose the greatest risk to human health.

Mrs. Moreira da Silva, Ph.D. Student, says, “Our findings highlight the need for implementation of infection control, prevention, and control (IPC) guidelines in small animal veterinary practices.”

“The inclusion of monitoring workers for nasal transmission of MRSA is also important to consider when designing IPC guidelines. Such measures may prevent the spread of multidrug-resistant bacteria in the community.”

“People should not be afraid to take their pets to the vet – it is still the best place for them to receive care.”