The Department of Agriculture, Environment and Rural Affairs (DAERA) states that “biosecurity is the prevention of disease-causing agents entering or leaving any place where they can pose a risk to farm animals, other animals, humans, or the safety and quality of a food product’’ (DAERA, 2023),while the MSD Veterinary Manual states that it is “all procedures implemented to reduce the risk and consequence of infection with a disease-causing agent’’ (Torremorell, 2022).
Regardless of your preferred definition and the species you treat, all animals that enter a veterinary practice pose a potential risk, whether to other members of their species, other species or even humans, in differing levels of risk.
Prevention is paramount
As with most branches of veterinary medicine, the best prevention of disease is the act of preventative measures. It is important to consider these measures before a patient enters the building and work out how you can adapt throughout the patient’s journey through the practice. Collecting thorough details of a patient’s areas of concern from a client is a straightforward initial step to good biosecurity, which can help you determine your next steps accordingly.
As with most branches of veterinary medicine, the best prevention of disease is the act of preventative measures
This can be seen in the preventative measures put in place for the recent outbreaks of avian influenza (AI), arguably the “hot topic” of biosecurity in avian patients for the past two years. Managing AI often involves reporting any bird with AI-like symptoms and preventing them from entering the building. This is defined as “bioexclusion”, a process wherein you prevent risk from entering the premises. If a case is suspected within the building, restricting the patient’s access to other areas will help maintain biosecurity across the rest of the site while you report your suspicions. This is known as “biocontainment”, the most generally used style of biosecurity in practice (as the animal is often on-site when diagnosed).
However, biosecurity is not limited to the “headline” or “hot topic” diseases and must be taken seriously as part of the day-to-day running of your practice.
How to ensure good biosecurity in exotic practice
The main differences to consider between exotic and small animal practice are the higher number of species considerations, the availability of suitable medications for treatment and the appropriate cleaning options.
Understanding and measuring risk: species considerations
Understanding the risk posed by a species or individual is important. By understanding the potential risks, you can create plans to minimise them.
Rabbits are the third most popular pet species in the UK and are likely to present at a practice regardless of whether it specialises in small animals or exotics. However, rabbits often carry conditions that pose a risk to themselves and others. Encephalitozoon cuniculi, for example, has been reported in 50 to 80 percent of rabbits, depending on the study (RVC, 2021). It is important to remember that the effects of E. cuniculi cannot be reversed (although they can be managed), so taking suitable precautions to prevent spread to other individuals is paramount.
Simple but effective steps that anyone in veterinary practice can take to avoid contamination are:
- Wearing appropriate PPE and minimising contact
- Using kennel liners to collect any urine passed
- Following the correct cleaning and disposal procedures
There is a preconceived notion that reptilian and avian species are more likely to carry zoonotic diseases, but what is not always considered is that outdoor rabbits can carry ringworm and mycobacteria – both of which are a risk to humans and other animals. While avian patients can carry more potentially dangerous zoonoses, reptiles are often carriers of zoonoses in the form of Salmonella or pinworms.
There is a preconceived notion that reptilian and avian species are more likely to carry zoonotic diseases, but what is not always considered is that outdoor rabbits can carry ringworm and mycobacteria
Birds are carriers of the Chlamydia psittaci bacterium, and clinical presentation can vary between individuals. Cases of human transference to owners with diseased birds are not uncommonly reported as it is readily transferred via faeces or airborne particles. Psittacosis can cause numerous clinical signs, such as pneumonia, resulting in serious illness or even death. In the global poultry industry, C. psittaci is deemed a significant cause of loss and, therefore, is not a rare disease. In fact, it is often described as underestimated in poultry workers (Smith et al., 2005).
Choosing a cleaning agent
Possessing a suitable cleaning agent is integral to maintaining cleanliness. In the past, a combination of agents was commonly used, but single-type agents are increasingly advertised as suitable for use in maintaining hygiene.
Even when cleaning frequently, it is crucial to regularly swab test throughout the practice to ensure correct levels of hygiene are being maintained.
There are numerous suppliers available for cleaning agents; however, consideration of species-specific interests and welfare is important. Avian species, for example, cannot have certain “mainstream” veterinary cleaners because they have been seen to cause respiratory distress. Therefore, the cleaner you use should be chosen based on what it is licensed for; for example, in an exotics practice that regularly sees poultry, you should aim for effectiveness against AI.
Even when cleaning frequently, it is crucial to regularly swab test throughout the practice to ensure correct levels of hygiene are being maintained
Depending on the disease (suspected or confirmed), aerosol-based cleaning should be used, regardless of practice focus, to maintain healthcare as it ensures hygiene is maintained in the hard-to-reach places of the practice (Cutts et al., 2021). This should be a minimum standard for cleanliness protocol in any practice seeing avian patients.
Risk classification
Defining an individual’s biosecurity risk is important and can help you prepare the level of biosecurity needed. Generally, use of a tiered classification system (Table 1) is required.
| Tier | Individual | Example | Ward | Suggested biosecurity protocols |
|---|---|---|---|---|
| Green (tier 1) | Patients with no evident disease | Neutering, routine health screens | Regular, species-specific wards | Basic PPE |
| Yellow (tier 2) | Poor immune status | Neonates, healthy unvaccinated and immunocompromised individuals | Isolation/own ward | Handle first using full PPE for reverse barrier nursing |
| Orange (tier 3) | Infectious patients which can be barrier-nurse contained | Infected with known zoonoses (ringworm, Salmonella, E. cuniculi, etc) | Regular wards with adaptations | Apron, gloves, barrier nursing, etc |
| Red (tier 4) | Highly infectious patients that can cause serious harm to other patients and/or people | Antibiotic resistant infections (C. psittaci, myxomatosis, bornovirus, etc) | Isolation | Full barrier nursing |
The way you tier patients can be practice-specific, but it generally follows the same train of thought with regard to risk. Using and implementing a classification system correctly should help provide clarity on the appropriate measure of how to handle, treat and house infected individuals, which, in turn, reduces the risk due to confusion among the team.
If in doubt, it is best to put the patient in a higher tier and downgrade it, rather than in a lower one. This will significantly reduce the risk of a biosecurity issue occurring.
Having a suitable up-to-date standard operating procedure (SOP) specific to each tier and a generalised SOP that encompasses a variety of species in a taxon is worthwhile.
Conclusion
Often, the concern in exotic practice is that biosecurity somehow differs. Yet, ultimately, biosecurity follows the same standard of thought whether you are in exotic or small animal practice. Developing an understanding of your patients, the potential infectious diseases they may carry and the risks involved will assist you in allocating a risk tier and ensure hygiene for that animal, other patients and yourself.
