Infection control quiz

Implementing an infection control strategy

WASHINGTON, DC – Preventing infection in critically ill veterinary patients is a very important daily activity for which there is very little research to guide best practices. Veterinary infection control practices tend to be more diligently followed in situations where zoonotic diseases are under consideration, said Louise O’Dwyer, MBA, BSc(Hons), VTS(Anaesthesia/Analgesia, & ECC) DipAVN (Medical & Surgical), RVN, presenting at the International Veterinary Emergency and Critical Care Society Conference. The threat of such highly contagious animal diseases, such as leptospirosis, tends to heighten awareness and prompt effective implementation of infection control practices. Unfortunately, critically ill veterinary patients are at high risk for developing many nosocomial infections that might not otherwise be considered highly contagious.

Human and veterinary infection control practices have gained heightened attention recently due to the emergence of methicillin-resistant Staphyloccocus aureus and methicillin-resistant Staphyloccocus pseudintermedius, in addition to several other multi-drug resistant organisms. Research has shown that effectively implemented guidelines rely on common sense and knowledge of basic principles; they must be suited to the local environmental conditions and problems. Healthcare workers must understand the principles and be effectively supported in order to successfully manage the risks.

Determining and assigning biosecurity status
Ideally, all patients admitted into veterinary clinics should be assigned a biosecurity status, based on signalment, history, physical findings, and/or laboratory diagnostics. This should be done as soon as possible, preferably before the patient leaves the exam or treatment area. This will determine where the patient will be hospitalized and the order of care. The appropriate biosecurity status should be placed on the hospitalization sheets, and the veterinary surgeon in charge of the case should assign appropriate biosecurity status to ensure that prescribed biosecurity Standard Operating Procedures are adhered to. This responsibility may be delegated to a qualified staff member, e.g. senior nurse. Ms. O’Dwyer explained that deliberate deviations from protocol are discouraged but permissible when considered to be in the best interest of the patient or the safety of personnel. Justification for such deviations should be briefly noted in the patient record and initialed by the veterinary surgeon in charge of the case.

Infection control strategies
Disease transmission is one aspect of an infection control strategy or protocol that should be considered for every patient.

Successful disease transmission depends on a source of infection, host susceptibility, and a route of transmission. Animal sources of infection can include endogenous microflora that are pathogenic to humans. Environmental sources of infection can include contaminated walls, floors, worktops, cages, bedding, equipment, supplies, feed, soil, and water. Host susceptibility to infection can vary greatly among the general population, with increased susceptibility seen in the unvaccinated; the very young and the elderly; those who are immunosuppressed or pregnant; or those with injuries that would allow a break in the normal defence mechanisms.

Pathogens are transmitted through direct contact, aerosol, and vector-borne routes. These need to be taken into consideration whenever hospitalizing patients and determining their biosecurity status. Hand hygiene, cleaning and disinfection, appropriate isolation facilities, and antimicrobial stewardship are all important facets of infection control in veterinary hospitals.

Hand hygiene
Hand hygiene is one of the most important aspects of infection control within hospital environments, but is one of the most difficult to enforce. Adherence to hospital guidelines is rarely as great as would be expected, explained Ms. O’Dwyer. Contributing factors include complex and hard to follow guidelines, feeling too rushed, a lack of education about its importance, bad hand hygiene habits, and dry and cracked skin due to hand washing.

She stressed that improving adherence involves including staff in product selection and choices, as personal preference and individual reaction to different products may assist in adherence. Education is also extremely important; healthcare workers must understand the importance of hand hygiene, the ramifications of poor practice, and the correct techniques.

Cleaning and disinfection
With the advent of Methicillin Resistant Staphylococcus Aureus (MRSA) and Methicillin Resistant Staphylococcus Pseudintermedius (MRSP) in veterinary hospitals, cleaning and disinfecting have heightened importance. Recovery of organisms from the environment has been documented months and years after becoming infected. A dirty environment or one with a significant biofilm allows protection of the organism and facilitates the spread of infection. Routine cleaning of contact surfaces such as door handles, light switches, computer keyboards or mice, and commonly gripped or touched areas that are not part of a routine cleaning regimen is imperative.

The first step in any cleaning protocol is to use a detergent that effectively cleans the biologic material and breaks up the biofilm from the surface. The detergent must be used with hot water and vigorously scrubbed and then rinsed from the surface. Residual standing pools of water should be removed as they can dilute the disinfectant that is applied next, and they may serve as reservoirs for replication and survival of microorganisms. Lastly, a disinfectant should be applied at the correct concentration, at the correct period of time following preparation, and for the proper duration to be effective.

Ms. O’Dwyer stressed the importance of understanding and keeping top of mind that bacteria are able to develop resistance to specific disinfectant classes. Therefore, hospitals should consider routine surveillance of the environment as an important component of an effective infection control practice.

Isolation facilities
In most cases, isolation facilities in veterinary hospitals are poorly designed and are an afterthought during construction. Because in many sites they are infrequently used, practice owners or hospital administrators are reluctant to invest large amounts of resources into properly creating a space that allows individual animals to be isolated from one another. A proper isolation facility should also have an area where staff can put on and remove appropriate and effective personal protective equipment or devices to protect themselves and prevent the spread of infection before and after entering the area. Ms. O’Dwyer said that since the healthcare workers may perceive the process as an impediment or a hassle, education and monitoring are extremely important facets of an effective policy. Healthcare workers should also be educated, or have guidelines to consult, regarding appropriate personal protective equipment necessary to protect against any known or suspected pathogens.

Antimicrobial stewardship
Ms. O’Dwyer concluded by saying that as we learn more and more about antibiotic resistance, the use of antimicrobials in companion animal practice, and not just food production, will gain increased scrutiny. The documented ability of certain microorganisms to share resistance genes places all antibiotic use under the microscope.

Designing an effective infection control strategy is multifactorial and should be done with a specific clinic in mind. Staff should be continually trained on practice protocols and how they should be carried out, and be expected to participate in continuing education programs on a regular, on-going basis. CVT