Deciding what disinfectant to use to clean the raptor chambers, wipe down falconry equipment, or clean the triage rooms at the raptor rehabilitation center can be overwhelming. It is imperative to have a basic understanding of how the different disinfectants work, what organisms they target, and the pros and cons of your disinfectant of choice.  

Distinction should be made between cleaning, sanitizing, and disinfecting. Cleaning refers to the physical or mechanical removal of dirt and debris. This will remove a portion of the germs on a given surface. Sanitizing is to reduce the germ colonies down to a less dangerous level, while disinfecting means to kill microorganisms (bacterial, viral, fungi, spores) on a surface (inanimate object) to an Environmental Protection Agency (EPA) designated low tolerance.  The EPA sometimes refers to disinfectants as “antimicrobial pesticides.” Always remember that most cleaners do not disinfect, and most disinfectants do not clean.

Disinfection of an environment or surface will reduce the number of pathogens, minimizing the risk of infection for the animal or human. Disinfecting will not result in sterility; this is achieved by other methods and for specific surfaces. The use of steam autoclaves in the veterinary setting is for sterilizing surgical instruments. Gas sterilization may be used when exposure to heat or radiation could damage the materials or equipment. 

For disinfectants to work properly, the surface areas to be disinfected must be free of dried debris and dirt. Raptor chamber walls should be scrubbed and hosed down before disinfecting. The floor should be raked to remove feathers, food parts and dried fecal matter. Organic matter weakens the penetrating power of disinfectants.  Disinfectants must stay wet and have contact with the surface they are treating. Contact times will differ between the various disinfectants and the concentration used. If the disinfectant dries before the recommended contact time, then the product must be reapplied to obtain efficient killing. Different pathogens (bacteria, viruses, fungi, spores, protozoa) require different approaches for effective disinfection, a one-product-fits-all does not exist. 

When choosing a disinfectant, three priorities of importance should be considered: the efficacy of the product, the sensitivity of the bird to exposure to the product, and the safety to the human who may be in repeated contact with the disinfectant. Disinfectant products have been associated with airway irritation, metabolic disturbances, contact dermatitis, and even neoplasia with prolonged exposure. Paying particular attention to the materials data sheet for the disinfectant of your choice is imperative to understanding how to correctly use the product and avoid toxic exposure to you and your birds. 

For a complete list of the different categories of disinfectants, their use and potential side effects go to the Center for Food Security and Public Health at Iowa State University www.cfsph.iastate.edu/Disinfection 

For the purpose of this document, commonly used disinfectants will be mentioned.

• Physical disinfection utilizes heat, light or radiation to eliminate microorganisms in the environment. Moist heat (steam) is more effective than dry heat (flame or baking) and requires less contact time. Sunlight and ultraviolet (UV) light can be used for inactivating or killing viruses, mycoplasma, bacteria and fungi, especially those that are airborne.  Freezing may help to reduce heavy numbers of bacteria, but will not totally eliminate them. Steam (at specific temperatures, pressure and exposure times) is the most effective method to eliminate protozoal oocysts (such as coccidia).

• Acetic acid or household vinegar is poorly active in the presence of organic matter. While it has some capability to kill select bacteria and viruses, it is not as effective as commercial disinfectants.

• Biguanides includes chlorhexidine and polyhexanide Chlorhexidine has a broad antibacterial spectrum but is limited in its effect against viruses, mycobacteria, fungi, and spores. Biguanides are inactivated by soaps and detergents. Chlorhexidine is best used to cleanse skin wounds.  Polyhexanide is found in F10SC. These products are toxic to fish and should not enter into the waterways.

• Halogen compounds include sodium hypochlorite (bleach), and are considered low toxicity, low cost, and easy to use. Bleach diluted to the proper concentration of 1/8 cup to ½ cup bleach to 1 gallon of water will be effective against many bacteria, viruses, mycobacteria, and fungi. Higher concentrations can be irritating to the mucus membranes, eyes, and skin. Bleach can emit chlorine gas, which can be detrimental to the respiratory tract. Always use in a well-ventilated area. The solutions need to be made fresh, as storage will deplete the activity, and bleach becomes inactivated in the presence of organic debris.  

• Phenols include products such as One Stroke Environ and Synphenol 3. These are coal-tar derivatives or synthetic formulations that have a strong pine odor. At 5% concentrations, they are considered bactericidal, tuberculocidal, fungicidal and virucidal.  However, 2% concentrations are highly toxic to all animals.

• Quaternary Ammonium compounds  (QAC) include Roccal, Zepharin, and D-256. They are efficient against many bacteria, fungi, viruses, and spores. They are not effective against mycobacteria, non-enveloped viruses in humans such as Poliovirus and Hepatitis A.  Most animal viruses are enveloped virus and are susceptible to this disinfectant. QACs can be easily inactivated in the presence of organic matter and are considered toxic to fish. F10SC is a very popular QAC disinfectant in veterinary medicine. It is composed of both Benzalkonium chloride (QAC), Polyhexanide (Biguanide) and added surfactants. This product is considered non-corrosive and nontoxic. F10 is commonly used as an environmental disinfectant, moderately effective in the presence of organic matter. It will treat a variety of bacteria, viruses, fungi, and spores. The fumes of F10SC appear to be non-irritating to the respiratory tract of the bird.

• Oxidizing agents are broad-spectrum products with bacteria, viral, fungal, and spore killing efficacy. Organic matter does not inactivate them. These products are also referred to as Peroxygen compounds. Accelerated Hydrogen Peroxide (AHP) is a synergistic blend of hydrogen peroxide, surface acting agents (surfactants), wetting agents (a substance to reduce the surface tension of a liquid), and chelating agents (a substance to reduce metal content and/or hardness of the water). An example of this type of product is Rescue. This product has been listed as a Category IV rating, which is considered the lowest toxicity rating given by the EPA.  Hydrogen peroxide at 5-20% is considered bactericidal, virucidal, fungicidal and at higher concentrations sporicidal. Virkon is a Peroxygen compound not containing AHP. It has similar capabilities as Rescue, but may be considered more toxic.

How to choose a disinfectant

As previously stated, three priorities of importance to consider when choosing a disinfectant are: the efficacy of the product, the sensitivity of the bird to exposure to the product and the safety to the human who may be in repeated contact with the disinfectant. Let’s compare three common disinfectants used in the United States: F10, Rescue, and Bleach: their efficacy and microorganisms they kill or reduce in number.

Disinfectant	F10 (QAC)	Rescue (AHP)	Bleach (Halogen compound)
Product inactivated by organic material	somewhat inactivated	not inactivated	inactivated
Contact time	2-30 mins	5-10 mins	10 mins
Expense	moderately	expensive	inexpensive
Microorganism efficacy
mycoplasma	+	++	++
gram + bacteria	++	++	++
gram negative bacteria	+	++	++
avian chlamydia	+	+	+
enveloped virus	+	+	+
non-enveloped virus	–	+	++
fungal spores	+	+	+
mycobacterium	–	limited	+
bacterial spores	+	+	++
coccidia	–	–	–
Notes:
limited efficacy
effective +
highly effective ++
not effective –

All three of the above disinfectants would be suitable to use. For any of these to work well, the organic debris (feces, blood, urates, food matter, etc.) must be cleaned and removed prior to disinfecting.  It is safest to remove the birds from the chambers when spraying with a disinfectant. The fumes can be toxic.  However, reports do indicate that F10SC fumes will not irritate the respiratory tract of the bird. In most instances, when the disinfectant has dried, it is safe to put the birds back into their chamber. Always rinse the water pans to remove any residue. Most important is to follow the dilution recommendations and contact times for your disinfectant of choice. An example is with Rescue: for viruses and bacteria, use a 1:64 dilution with a contact time of 5 minutes, but for fungal, use a 1:16 dilution for a contact time of 10 minutes. This will be important for raptor chambers and to reduce the aspergillus spores. Because one product will not fit all needs at all times, some rehabilitation centers and raptor breeding facilities will alternate between bleach and F10SC or Rescue. Never mix disinfectants together; this can be hazardous to your health.

Suggested Reading:

• Center for food security and public health

• Keep it clean: infection control and biosecurity in veterinary medicine, by the numbers.   Virox Animal Health

• Practical infections control guideline: Australia infectious disease advisory panel (AIDAP)