Abstract

Due to the variety of different species and their often foreign origin, the introduction of novel pathogens becomes inevitable, resulting in zoonotic or nosocomial infections. Biosecurity is the methodical application of a management protocol to prevent the introduction and transmission of such pathogens. The application of a few simple, cost-effective techniques with concurrent use of appropriate chemicals during the daily routine of the practice will significantly reduce the risk of such infections.

Introduction

Nosocomial and zoonotic infections pose a high risk on patients and involved humans and possibly occur more often than records show.^1,2 These infections are undesirable, expensive to the veterinarian and client, may be life-threatening and, most importantly, can be prevented.¹ Factors that predispose a patient to nosocomial infections can be classified as intrinsic (age, sex, breed, immune status) or extrinsic (invasive procedures and staff exposure).¹ The most important aspects regarding the prevention of these infections are staff education, aseptic technique, basic biosecurity principles, barrier precautions, and appropriate sanitation and disinfection.^1,4 From the evidence presented, it has become vital that the risks of acquiring such infections be eliminated or at least mitigated.

The Need for a Biosecurity Program in the Exotic Animal Practice

In the exotic animal practice the veterinarian deals with peculiar and unusual species.

Due to the variety of different species and their often foreign origin, the introduction of novel pathogens becomes inevitable, resulting in zoonotic or nosocomial infections, for example B-virus (macaques), salmonellosis (reptiles), psittacosis (parrots), and the haemorrhagic fevers complex.²

The prevention of these infections through the identification of risk factors and the development of preventative measures are the main objectives of hospital biosecurity.¹ The reality, however, is that proper biosecurity practices are often seen as a cost which can be minimised as opposed to a quality assurance matter that deserves careful attention in the delivery of the medical care of the patient.¹

Principles of Biosecurity

Biosecurity is the methodical application of a management protocol to prevent the introduction and transmission of pathogens.³ The main objective is to eradicate any pathogen or to render it inert with one or a combination of chemicals.⁵

Product Selection

If it is accepted that the risks are increasing, then product selection is a critical decision and cannot be considered lightly or by lay or ignorant persons.¹ Efficacy, toxicity and performance reports must be studied in depth for each product to ascertain relevance and adequacy and selected products must be registered with the relevant authorities.¹

There are many products available to implement in such a protocol; however, it is the author's opinion that the F10 product range from Health & Hygiene (Pty) Ltd. is ideal for such purposes due to its safety, non-corrosive properties, minimal tissue irritation, short contact time, and the unique synergic activity of its quaternary ammonium and biguanide compounds.³ Independent tests have shown it to be effective against a wide range of viruses, bacteria, fungi, including spores.⁵ Due to the intricate interactions of the different components, resistance is unlikely to occur, making it a sustainable and responsible product choice.⁵ Other reputable products for use as surface or air disinfection include Magistral PF^TM and Magistral L^TM (Bedson), SaniChick (SaniChem) and Clinafarm® (Intervet), although these are more commonly applied in the poultry production industry.

A Basic Biosecurity Policy

 Risk identification: Areas where cleaning, disinfection or sterilisation is needed should be identified.¹

 Risk reduction: The goal is to decrease microorganisms to the lowest possible level in the most practical and economical way.¹ Staff should be trained in elementary hygiene principles and routine cleaning procedures.¹ Hand washing, damp-dusting, vacuuming and fogging should form the standard.¹

 Risk management: The biosecurity policy achievements should be maintained.¹ This is monitored through weekly inspections.¹ It is recommended that microbiological surveys be carried out at least quarterly.¹ Procedures should be refined and if necessary, staff should attend refresher courses in biosecurity.¹ A simple protocol is more easily complied with and tends to be more cost-effective.¹

Methods

Hand Hygiene

Transmission of microorganisms between patients via the hands of staff is the main route of disease transmission.³ It is widely accepted that a thorough handwashing protocol may result in a significant reduction in nosocomial as well as zoonotic infections.³ It therefore forms an essential part of the basic hygiene and biosecurity protocol at any facility. New studies in healthcare facilities show that handwashing practices are suboptimal.⁶ Proper facilities should be readily available, including running hot water.⁷ Hands should be washed between each patient with an appropriate contact time for the particular product used.^3,7 Quick-drying, alcohol-based hand gels are a practical, though more costly, supplementary product.⁷

Hospitalization

Most of the exotic animal species that require hospitalisation are usually very ill and, as a result, susceptible to opportunistic and novel infections.¹ For this reason, these animals must be kept in a dark, quiet and warm environment, away from predator animals (dogs and cats) to reduce stress, which may compound their susceptibility. An incubator is an ideal enclosure for these purposes. Patients with suspected infectious and/or zoonotic disease should be placed in isolation.⁷ Hospital staff should have in-depth knowledge regarding the handling of such patients (i.e., they should be treated last of all patients) and it is preferable to have dedicated staff for the treatment of these animals to decrease the risk of iatrogenic transmission to other patients.⁷

Surface Disinfection

The necessity for the implementation of an adequate disinfection protocol for working surfaces cannot be overemphasized.⁵ A dedicated spray bottle containing a suitable disinfectant and disposable paper towel works well for this purpose.⁵ Adequate contact time is essential.³

Protective Clothing

The author recommends the following principles regarding protective clothing:

 General protective clothing: used in general practice, every day. Hospital scrubs and easily removable shoes. Such protective clothing should never leave the practice (including for washing purposes) to minimise the risk of fomite transmission.⁷

 Isolation protective clothing: used with animals with zoonotic and/or infectious diseases. Isolation protective wear should be worn over general protective clothing (i.e., disposable gowns, overshoes, hairnets, facemasks, gloves, etc.⁷). These items should remain in the isolation area.

Equipment

Designated equipment for each room/area should be identified and clearly marked as such.⁷ Endotracheal tubes, feeding tubes, neonatal feeding bottles, thermometers, stethoscopes, kidney dishes are but a few examples of equipment that all require proper disinfection after use, especially between patients.^1,7,8

Bedding or Substrate

The bedding or substrate of a patient with an infectious disease should be discarded and replaced after proper disinfection of the area.⁷ Blankets and cushions should be presoaked in a disinfectant prior to washing.⁷

Fogging

(Air sanitisation by means of aerosol microdroplets). This application method is highly effective and economical if done as prescribed.¹ The goal is to reduce airborne pathogens and to disinfect all contact surfaces including inaccessible areas.^1,5 Fogging should commence immediately or as soon as possible after the discharge of a patient with a zoonotic or infectious disease. The air-conditioning system should also be on to facilitate the cleaning of the unit.⁷ The recommended application time is 35 minutes.¹⁰

Air Quality

Air-conditioning systems can be a major source of contamination and therefore should be cleaned and maintained on a regular basis.¹

Biofilm Removal

Microorganisms persist in an environment despite surface disinfection due to the inability of certain disinfectants to penetrate the protective biofilm (an adhesive material enclosing colonies of microorganisms attached to a surface⁹), rendering the microorganisms (bacteria, fungi or yeast) as a reservoir for infection¹⁰. These biofilms can be inert (air-conditioning, humidification and filtration systems, intravenous catheters or prosthetic devices), or biological (granulomatous wound healing tissue or respiratory epithelium).¹⁰ The removal of biofilms as a risk factor consists of an integrated approach where appropriate antimicrobials are combined with surface cleaning and disinfection using a compound chosen for its detergent, disinfecting actions as well as tissue-friendly properties.¹⁰ Biofilm found on hard surfaces and the inside of pipes can be successfully removed by the collective use of a purpose-built cleaner.¹ The broad-spectrum F10SC Veterinary Disinfectant product is recommended by the author, as it adheres to all abovementioned requirements.

Footbaths

Footbaths should be placed just outside the room where infectious patients are hospitalised.^5,7 Astroturf^TM may be placed inside the footbath to facilitate soil and debris removal.⁵ These footbaths should be cleaned and refilled daily.⁵ Both feet should be immersed before entering the room.⁵

Food Preparation and Food/Water Containers

All food should be prepared prior to treating the animals in an attempt to prevent the spread of disease between animals.¹¹ These areas and equipment should be disinfected immediately after preparation is done, at least twice daily.¹¹ Designated and clearly marked stainless steel food and water bowls should be cleaned daily or if practically feasible, twice daily.¹¹ The bowls should be left to dry to increase the contact time of the disinfectant.^7,11 Bowls from infectious patient should be washed and disinfected in the isolation ward or washed last with F10SC Veterinary Disinfectant used as the detergent.⁷

Drainage

Effluent from isolation areas should not run through areas which any animals have access to.⁷ Drains should receive special consideration in the cleaning and disinfection program.⁷

Conclusion

Nosocomial and zoonotic infections might not be a regular occurrence and often go unnoticed and are therefore underdiagnosed.¹ The threat they pose is of such significant magnitude that it cannot be ignored.¹ By implementing a few simple, cost-effective techniques and applying them as part of the daily routine in the practice, such risks can be near eliminated, protecting patients, staff and clients as well as the profession's reputation.

Acknowledgements

1.  Bird & Exotic Animal Hospital, Onderstepoort Veterinary Academic Hospital, Pretoria

2.  Johannesburg Zoo, Johannesburg

3.  Monica Burger, BSc, University of Pretoria

References

1.  Muller L, Temperley J. The need for biosecurity in a veterinary practice today. Health & Hygiene: The Facts. 2007;5. www.healthandhygiene.co.za/issues/issue5/

2.  Weinstein RA, Weber DJ, Rutala WA. Risks and prevention of nosocomial transmission of rare zoonotic diseases. Clinical Infectious Diseases. 2001;32(3):446–456.

3.  Health & Hygiene: The Facts (homepage on the Internet). Biosecurity and infection control best practice campaign. Stage 2: Hand hygiene - the cornerstone of infection control. No date [cited 2014 Apr 26]. Available from: www.healthandhygiene.co.za/issues/updates3/index.htm

4.  Kahn CM, ed. The Merck Veterinary Manual. 10th ed. Whitehouse Station, NJ: Merck & Co. Inc.; 2010.

5.  Samour J, Naldo J. The use of F10 in falcon medicine: practical applications. Health & Hygiene: The Facts. 2008;8. www.healthandhygiene.co.za/issues/issue8/

6.  Larson E, Kretzer EK. Compliance with hand washing and barrier precautions. Journal of Hospital Infection (supplement). 1995;30:88–106.

7.  Health & Hygiene: The Facts (homepage on the Internet). Biosecurity and infection control best practice campaign. Stage 4: Isolation and terminal disinfection in veterinary practice. No date [cited 2014 Apr 26]. Available from: http://www.healthandhygiene.co.za/issues/updates5/index.htm (VIN editor: link was modified on 10/21/15)

8.  Barrows M. F10, a novel product range most suited to zoological medicine. Health & Hygiene: The Facts. 2007;6 www.healthandhygiene.co.za/issues/issue6/.

9.  Lawrence E, ed. Henderson's Dictionary of Biology. 14th ed. Pearson Education; 2008.

10. Verwoerd DJ. Biofilms: importance and control in biosecurity and disease management from a veterinary perspective. Health & Hygiene: The Facts. 2009;12.

11. Parry-Jones J. The role of F10 products in the aviculture health and hygiene strategy at the new international centre for birds of prey. Health & Hygiene: The Facts. 2008;9 www.healthandhygiene.co.za/issues/issue9/.