Adding Germicidal Ultraviolet (GUV) Light Disinfection to Veterinary Infection Control Plans

While the COVID-19 pandemic caused global health panic, economic losses, and high rates of morbidity and mortality and persists today, we can take some solace from the tragedies in knowing that we now know and understand a lot more about ways to ensure we protect ourselves against respiratory threats who possess the ability to spread not just through direct contact and exposure but also via the aerosol transmission route.¹ Further, we know that influenza (human and other forms) can spread via more than one means of exposure^2–5 Because we now understand that aerosol viral transmission can occur with various organisms, we recognize the need to improve our infection control plans, taking into account not just surface disinfection and HVAC filtration but also ensuring we provide a safe and effective means to combat the threat of aerosol spread of infectious diseases.

Be it COVID-19, influenza A or B (human forms), the potentially zoonotic high pathogenic avian influenza, or a non-zoonotic viral infection such as canine distemper, feline herpes or feline calicivirus, or bacterial risks such as may be found with Bordetella bronchiseptica, veterinary infection control plans need to be robust, multi-modal, and revised to meet the current needs of the health climate and environment. Now more than ever, the human-animal bond (HAB) shows us the interconnectedness of humans, animals, and our environment, and one way the veterinary community can minimize risks starts with controlling the veterinary environment where we practice, minimizing risk from the time a patient and client enter the vet hospital (grooming/boarding facility, etc.) to the time they leave. Further, by ensuring an overarching infection control plan, you protect employees, minimize sick days and loss of productivity, and improve morale.^6–8

When developing an infection control plan, consider any possible hazards. These include physical dangers as well as infectious and non-infectious risks. Further, understanding and recognizing how diseases spread and hospital-acquired infections (HAIs) manifest aids in your ability to develop a comprehensive plan that uses a multi-modal approach to ensure the most protection. Understanding that the size of particles matters and how that translates into appropriate protective measures further necessitates attention to detail when devising one’s infection control plan remains paramount.^9,10

Understanding the various types of disease transmission, including the role of the environment (fomites and mechanical transfer), ingestion, dermal exposure, sexual/vertical transmission, vectorborne transmission, and inhalation, can best protect your practice.¹¹ Inhalation occurs via both droplets, which are too large to be sustained in the air for long and drop to the ground nearby, and particles that remain suspended in air and are aerosolized, traveling distances and putting those not in the immediate vicinity at risk.¹² Learn more about airborne transmission.

This distinction between aerosolized particles that can travel for distances and over time vs. those particulates that drop to surfaces helps illuminate why standard infection control measures, e.g., hand hygiene and standard cleaning of surfaces, don’t fully protect against numerous infections. What additional means do we have that could be added to current infection control plans to address this aerosolized disease threat?

Germicidal ultraviolet (GUV) has been used for over a decade for disinfection and disease eradication, with research dating back decades.³ However, since the COVID-19 pandemic, technology has gained ground as scientific evidence continues to amass, showing improvements in infection control prevention and eliminating outbreaks. GUV can boost your protocols and protective measures and address airborne transmission in ways other methods cannot.

But what is GUV? Simply put, GUV uses ultraviolet (UV) light and energy to kill various organisms (bacterial, fungal, or viral). GUV uses energy created via UV-C, not A or B radiation, which is much less risky to humans and, when appropriately installed, rendered generally safe. Ongoing research aims to improve our understanding and knowledge of the safety levels and measures needed to ensure the safety of human health while using these units to remove pathogens.^13,14

Disinfection can be provided via GUV water treatment, for example, or via upper-room GUV (UVGI) units. These provide a zone where UV energy is in the upper regions of a room, where people and animals aren’t, but the airborne pathogens can reach.¹³

The benefits seen from GUV continue to be elucidated. However, to date, they include:^1,4,9

• Reducing biofouling on air-handling cooling coils enhances energy efficiency by maintaining optimal airflow and cooling performance while preventing mold growth that can compromise indoor air quality and lead to costly maintenance issues
• Improving indoor air quality
• Aiding in disease prevention (by its ability to kill, not just trap infectious agents in the air and on surfaces)
• Being an environmentally friendly, non-toxic means of disease prevention
• Possessing a high effectiveness rate, including against organisms that may have developed resistance to various chemicals or other modalities of destruction (This was established in the early days of GUV use, as early as 2012, as demonstrated by Dai et al.)¹⁷
• Reducing infectious disease outbreaks (e.g., kittens in a shelter)^15,16
• Decreasing overall bioburden of possible infectious agents on surfaces and in the air¹⁸

Standard air purifiers work by collecting large droplets. While they prevent exposure, they trap and do not inactivate or kill infectious droplets. If they malfunction, the HEPA filter or related mechanism is full/not properly cleaned/changed or maintained, or if they are overloaded, diseases can still spread. Still, they serve a purpose and can be beneficial as part of a comprehensive plan. However, taking the example of superspreaders shedding significant levels of COVID-19, for instance, and that air purifiers may be overwhelmed, standard infection control measures aren’t always enough for some diseases.^19–22 What if you could take it one step further and actually inactivate or, better yet, kill infectious agents through the use of GUV? Including them in your infection control plan seems like a no-brainer.

When considering the purchase of a GUV product for your infection control plan, it is essential to keep in mind where oversight occurs and what certifications may ensure further quality control, as well as speak to the overall safety and science backing the product.

1. The EPA (Environmental Protection Agency) requires that all UV devices that claim to eliminate or inactivate microorganisms such as bacteria and viruses are classified as ‘pesticidal devices’ under the Federal Insecticide, Fungicide, and Rodenticide Act (FIFRA). While these devices do not require EPA registration, they must be manufactured in EPA-registered facilities. Additionally, the EPA mandates that the product label includes the EPA Establishment Number of the facility and clear instructions for safe use and precautions to ensure the device is effective and, when used according to manufacturer directions, is not harmful. These requirements help protect consumers and ensure accurate and reliable product claims.²³ Additionally, the EPA mandates proper labeling, which includes instructions for safe use and any necessary precautions to ensure the device is effective and not harmful when used as directed.
2. Certifications can be obtained. While not obligatory, these certifications, e.g., from agencies such as ETL and UL, indicate that the product has undergone testing to ensure proper compliance with North American electrical and mechanical safety standards. Although not legally mandated, obtaining these certifications is strongly recommended to guarantee the product’s safety and adherence to rigorous safety standards.^24,25
3. Industry standards, including guidelines established by ASHRAE (The American Society of Heating, Refrigerating, and Air-Conditioning Engineers), play a crucial role in shaping the testing criteria for UV disinfection devices. These guidelines emphasize that UV devices should not produce ozone, as ozone is a known respiratory irritant and harmful to health. Furthermore, these guidelines prioritize the safety of UV devices in occupied spaces, providing essential assurances for their use in environments with people present.^26,27

It is paramount to note that all Aerapy^® products meet and exceed the necessary regulatory and non-regulatory requirements. Further, products are backed by independent testing and numerous certifications.

The six components of an infection control plan remain essential to establishing standard operating procedures (SOPs) that minimize the risk of various hazards in the veterinary workplace.^6,28

1. Planning: Ensure all plans receive regular updates and review. All staff shall be required to review the plans and understand implementation measures routinely. Ensure planning accounts for infectious and non-infectious risks and differentiates between those that are and are not zoonotic.
2. Prevention: Strategies used to mitigate and prevent hazards, including but not limited to various protocols on the use of proper PPE, sanitization, hand hygiene practices, pest control measures, laundry procedures (dos and don’ts), suitable handling of infectious and chemical waste products, and the proper handling of wounds/injuries are all relevant.
3. Infected Patient Management: Specific known disease entities require distinct and often unique handling protocols. While we cannot account for all possible infectious etiologies, we can do our utmost to minimize risk by maintaining protocols for isolating and treating infected individuals who pose a potential threat to other animals or humans. We seek to prevent disease from spreading through isolation, proper PPE use, and additional measures.
4. Cleaning, Disinfection, and Sanitation: Certain organisms, environmental conditions, surfaces, and locations within the veterinary environment will require different protocols for cleaning, disinfection, and sanitation. Depending on each scenario, a combination of all three may be necessary. We want to prevent aerosolization by avoiding high-pressure washers or other modalities that permit particles to become airborne. Further, proper hand hygiene protocols should be in place. Hand sanitizers should be available in multiple locations, especially if hand washing isn’t feasible. However, ensure protocols explain that not all infectious agents are inactivated by standard hand sanitizers, and additional measures are often warranted to provide protection.
5. Proper Personal Protective Equipment (PPE) Use: Standard protocols for basic animal handling should include using PPE, e.g., disposable gloves and items needed for specialized situations, including non-porous gowns, booties, head covering, and special equipment when required.
6. Education: Staff should routinely receive updated information on the various safety hazards in their environments, including but not limited to non-infectious diseases and those that are contagious, modes of transmission, current protective measures in place, and how these work to prevent disease or disease spread. However, education doesn’t stop with staff; it must include client education about commonly encountered hazards, infectious risks, and prevention recommendations.

When considering infection control, most automatically think of high-trafficked areas like waiting rooms. We have an obvious commingling of different species, even with waiting rooms where cats/dogs/exotics are separated, because you have to consider people in the mix. However, what about areas where you may unintentionally cause particle aerosolization? Treatment rooms, dental suites, laundry rooms, and other locations where you may disturb dust, particulates, and aerosolized materials simply by daily activities or practices such as lancing abscesses or cleaning, scaling, and polishing teeth.¹¹

Further, while respiratory viruses or bacterial respiratory agents provide an apparent potential risk for aerosolization and a correlation between infectious hazards and the need to decrease that risk, what about HAIs? We could contaminate the environmental surfaces and aerosolize particles through daily activities such as routine cleaning, shaving animals, cleaning wounds, and more. Thus, a GUV system can protect against expected respiratory threats and unforeseen culprits.

All veterinary facilities, whether a small rural general practice veterinary hospital with one doctor or a significant urban veterinary emergency and specialty center, must protect their patients, clients, and staff and minimize negative environmental impacts. An infection control plan is vital, ensuring that staff understands everyday SOPs and that an up-to-date emergency response plan is available in case of disasters or unforeseen events.

Not only does a well-established, regularly re-evaluated, and updated infection control plan help maintain order and guide SOPs, but it can also save lives. Infection control plans ensure the safety and well-being of staff, animals, and the environment. Minimizing disease risk to all improves the HAB and health outcomes. When developing an infection control plan, consider including and ensuring all of the following are addressed/implemented:^6,7,29,30

• Utilize dedicated exam rooms for infectious diseases and follow pre-established proper cleaning and disinfecting protocols once the infectious animal has left. This includes contact time for any products used and how long the room should remain vacant before resuming use.
• When feasible, it is ideal that all veterinary facilities have an isolation room(s) with separate ventilation systems from the main hospital/location for infectious patients, especially those with respiratory illnesses at high risk of spreading.
• Ensure that dust and moisture are kept to a minimum at all times, as these increase the risk of aerosol spread and the development of bacterial and fungal contaminants and growth. Humidity should also be minimized, as it plays a key role in the aerosol spread of organisms.^4,31,32
• Proper use of PPE – However, ensure staff understand the limitations of PPE and that they are one of the last steps in protecting against infectious disease transmission, not the end-all-be-all.³³
• Ensure ventilation systems and HVAC systems are:^4,34–36
  1. Appropriate for the size of your facility
  2. Appropriate for the number of animals/people seen on any given day
  3. Adequately maintained and regularly inspected to maintain proper working order. Ensure the working order of all HVAC parts, including but not limited to the filters, humidity controls, ductwork, exhaust handlers, and related equipment
  4. Utilize and properly maintain air filters (e.g., HEPA)
  5. Regularly evaluate for problems (e.g., annually to bi-annually)
  6. Achieve a minimum of five air exchanges each hour³⁷
• Ensure that appropriate ventilation exists at all times, especially in areas of high risk of disease transmission
• Consider using non-ozone-producing air purifiers to trap larger particles in common areas. Routinely changing the HEPA filters is paramount to ensuring key function. While air purifiers can reduce particle counts, they are insufficient to protect against infectious diseases without complementary measures like UV-C irradiation and proper ventilation.^38,39
• Establish effective strategies to manage the disposal of infectious items.
• Address the risk of aerosol disease transmission by upgrading to a GUV system with a reputable company with well-researched, evidence-based products and then ensuring routine maintenance and care.

If it isn’t clear yet, it should be that having a comprehensive infection control plan for your facility improves the health of your micro-environment, from the employees to the clients to the patients, and helps reduce HAIs and environmentally acquired infections. Aerosol disease transmission, well-recognized and much better-appreciated thanks to lessons learned from COVID-19, can be successfully all but eliminated by adding a GUV disinfection system. GUV takes the standard precautions and measures from PPE to proper hand hygiene practices, to distancing and shielding, to the next level, helping to eliminate the risk of aerosolization transmission of numerous zoonotic and non-zoonotic agents.

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