Classes Of Disinfectants And Their Uses

There are literally hundreds of disinfectants out on the market now. So–which disinfectant do you pick? I will offer an overview of the different classes of disinfectants, their uses, drawbacks and strong points, and an idea of approximate costs for each class. If you are still in doubt after reading this article, do not hesitate to consult with a qualified avian vet for assistance in deciding which disinfectant, or combination, is best for your situation. It is not uncommon to need more than one kind of disinfectant to combat different types of pathogens in the same aviary. Hospitals, on the average, have over 14 different types of disinfectants in use at any given time; your home may not need 14, but just one may not be enough!

DEFINITIONS USED TO DESCRIBE CONTROL OF MICROORGANISMS

ANTISEPTIC

An agent that can be used as directed to reduce the microbial population found on skin. The maximum useable concentration of antiseptic is limited by risk of skin and mucous membrane irritation.

DISINFECTANT

An agent that will destroy many of the disease-causing microorganisms present on the surface of an inanimate object. A disinfectant claim is granted by the EPA to any solution which will destroy the following three microorganisms using an official AOAC (AOAC: Association of Official Analytical Chemists) procedure: Staph aureus, Pseudomonas aeruginosa, and Salmonella choleraesuis. A disinfectant label does not imply or include efficiency against viruses, mycobacterium, protozoa or heat-resistant bacterial spores.

GERMICIDE–(Also called Bactericidal)

An agent that kills certain specified types of pathogenic microorganisms when used as directed. The labels of these agents make minimal claims, such as excluding specific bacteria by name. The limitations of these claims can only be found by closely reading the labels. A germicide does not automatically kill spores, viruses, tuberculosis or fungi.

SANITIZER

An agent that reduces microbial contamination on the surface of an object to an acceptable level. Sanitizers must not leave a harmful residue.

STERILANT

An agent that destroys all microbial organisms including heat-resistant bacterial spores. Sterilization can be achieved by boiling, autoclaving or exposure to toxic chemicals. Solutions that contain chlorine or glutaraldehyde are frequently labeled as chemical sterilants.

SPORICIDE

An agent that kills two specific types of vacuum-dried bacterial spores, according to specific AOAC test requirements.

TUBERCULOCIDAL

An agent that kills mycobacteria and especially M. tuberculosis according to procedures recently defined by the EPA (Environmental Protection Agency). A disinfectant or germicide are not automatically considered to be tuberculocidal.

VIRUCIDE

An agent that kills certain specified types of viruses when used as directed. An EPA approved label claim must state which viruses the agent has been proved effective against.

CLASSES OF DISINFECTANTS

FIRE AND FREEZING

Freezing temperatures will deactivate some infectious organisms, but many, including viruses will survive. The longer the freezing time, the lower the survival rate for most organisms, but it won’t kill everything.

Flame is an excellent cleaner. Gas torches will kill any known living organism; remember, the solution to cleaning up after epidemics has been to burn down anything that was contaminated! But flame is obviously limited in its uses–it’s hard to disinfect wood nest boxes and plastic objects with flame, and it will often discolor metal surfaces.

STEAM

Pressurized steam directed into cracks and corners is an excellent sterilant. It is, however, quite disruptive to birds, especially during breeding, and it can be costly due to equipment rental/purchase charges. It is best to thoroughly wash all equipment prior to steaming it.

SOAPS/DETERGENTS

Soaps and detergents do not disinfect. But they help remove surface organic debris so it does not interfere with the function of disinfectants. Always rinse soap or detergent off completely before disinfecting, and never mix with disinfectant unless the disinfectant instruction specifically state that it is safe. Avoid oral ingestion of these products, as they can cause intestinal upset, and can irritate mucous membranes.

ALCOHOLS

Alcohols are the base ingredient for many other disinfectants–for example, Lysol spray contains 79% ethyl alcohol and only 0.1% orthophenylphenol. When used as a surface spray or solution on inanimate objects, alcohol is an excellent pathogen destroyer. But it must be left in contact with the item to be disinfected for long periods to do its job–20 minutes contact time is considered proper for disinfection with ethyl alcohol. The higher the “proof” of an alcohol product, the better disinfectant it is, but the more volatile and evaporative it will be. Isopropyl alcohol is not considered to be a disinfectant–it’s main use is as a skin wipe to remove loose organic debris from the site of a wound or injection.

ADVANTAGES

Low cost; effective against many pathogens with correct contact time

DISADVANTAGES

Long contact time required for disinfecting action; only certain types of alcohol contain true disinfectant properties; may dissolve synthetic surfaces; fumes may be irritating and contain a fire hazard risk; not effective against some viruses; evaporates quickly, so items being disinfected must be physically soaked in alcohol to obtain disinfection

CHLORHEXIDINE GLUCONATES

BRAND NAMES: Nolvasan, Virosan, Hibitane, Hibistat

Chlorhexidine products are often used as disinfectants for inanimate objects or antiseptics for cleaning skin wounds. Some chlorhexidine compounds contain alcohol, and these have been found to have superior antimicrobial properties to those containing only chlorhexidine. Chlorhexidine is effective against many bacteria, and yeast (especially Candida). It is not effective against most viruses, mycobacteria spores and Pseudomonas. Hexachlorophene has been suggested to be a potent carcinogenic. Some aviculturists use chlorhexidine as a water additive for control of pathogens–this is not recommended by the manufacturers, as these products were never meant for ingestion, and long-term effects have not been studied.

ADVANTAGES

Recommended as a water pan additive in incubators and brooders for control of aspergillus fungus; effective against Newcastle virus; not corrosive to equipment; readily available, medium cost

DISADVANTAGES

Poor efficiency against most viruses and many gram-negative bacteria including Pseudomonas (Virosan is the exception–it is effective against Pseudomonas); must be discarded and re-mixed daily; not effective in the presence of organic debris; not effective against bacterial spores or mycobacterium

CHLORINE

BRAND NAMES: Clorox, Purex

The best known member of this class is sodium hypochlorite (bleach). Bleaches are very harsh but effective. They attack pathogens, organic debris and living tissues equally well. Bleach can create toxic fumes which can lead to chemical pneumonia, skin and eye irritation or burns. It is recommended to wear protective clothing and eye gear when using bleach.

ADVANTAGES:

Bleach is inexpensive; easily available without a license; depending on the concentration at which it is mixed it can kill most bacteria, viruses, and mycoplasmas; it is a potent deodorizer, and works best in the presence of sunlight which releases more free radicals (which destroy cells, including pathogens).

DISADVANTAGES

It is very caustic to tissues and equipment; very rapidly inactivated by organic debris (any dirt left on the object being disinfected will interfere with the action of the free radicals, up to the point where no chlorine is left to act on the actual pathogens); it loses its effectiveness quickly while still on the shelf in the bottle; not all brands of bleach, and not all production lots are the same concentration, so the standard dilution of 1/2 cup to a gallon of water (5:25% concentrate) may not always turn out to be the same strength; prolonged contact may be required for heavy sterilization, and the solution may require freshening every few hours. Bleach produces carcinogenic by-products, and must be used in a well-ventilated area; all objects treated with bleach must be well rinsed and allowed to dry before birds are allowed to contact them.

STABILIZED CHLORINE DIOXIDE

BRAND NAMES: Oxyfresh Dent-a-gene (full strength stabilized chlorine dioxide), Oxyfresh Cleansing Gele’ (detergent with stabilized chlorine dioxide added)

Stabilized chlorine dioxide is a chlorine derivative which is a powerful oxidizing agent. It can destroy many pathogens, including bacteria, viruses, fungi and protozoa. Many studies have suggested that stabilized chlorine dioxide is a superior disinfecting agent to sodium hypochlorite (bleach). It is used in Europe to treat drinking water because it does not form carcinogenic by-products like sodium hypochlorite does. Stabilized chlorine dioxide has been shown by Dr. Branson Ritchie DVM, to inactivate avian polyoma virus at a level of dilution of 1:200.
A detergent product containing stabilized chlorine dioxide is a good washing/soaking product for syringes, dishes and other hard surfaces, and can also be safely used on the skin of avian caretakers. Chlorine dioxide is an excellent deodorizer; the oxidizing properties destroy odor-causing molecules.

ADVANTAGES

Safe for use around birds and humans at recommended working dilutions; deactivates avian polyoma virus in 1 minute contact time; diluted solution creates no harmful fumes and is safe to use on skin or other surfaces; diluted solution at 1:200 is good for 7 days once mixed if kept sealed and out of direct sunlight; when first mixing up solution, the fumes created may be used to fumigate brooders. Medium cost–1 pint makes up to 16 gallons of diluted solution.

DISADVANTAGES

In undiluted form, fumes of stabilized chlorine dioxide may be toxic to living tissue; rapidly deactivated by organic debris and exposure to sunlight.

GLUTARALDEHYDES

BRAND NAMES: Wavecide, Cidex, Sporcide, Banacide, Sterol

This is a relatively new class of disinfectants which has come out within the past 25 years. The chemical action is to deactivate DNA and RNA proteins. They will deactivate most bacteria (including mycobacteria), viruses, and chlamydia. They are very stable and most work well even in the presence of organic debris. When mixed up in solution, they last a long time, making the cost per use fairly low. But they are very expensive to purchase initially compared to other disinfectants, and have many possible side effects, including tissue toxicity, irritation to the eyes, mucous membranes, respiratory tract and skin. Some glutaraldehyde formulas are corrosive to metals, others are not; read the label of a particular product to find the corrosive properties of that product. Never, ever mix glutaraldehydes with any other cleaning or disinfectant product.

ADVANTAGES

Equally effective in water of any temperature or hardness; effective against essentially any pathogen, even in presence of organic debris; solutions are good for longer periods than any other disinfectant available which lowers cost per use; speed of killing pathogens is very fast compared to many other disinfectants; available in many forms, including sprays, concentrates and bulk volumes

DISADVANTAGES

May require a medical license to purchase from some suppliers; EPA testing did not include all animal and bird pathogens–assumptions were made regarding those, based on results of human pathogen testing; may irritate respiratory system if not used in extremely well-ventilated areas; may cause eye, skin or mucous membrane irritation or damage with some brands; must be well-rinsed before allowing birds contact with cleaned surfaces; may cause skin irritation, yellowing or peeling; concentrated forms not available in all states; some forms/brands of product may be corrosive/caustic than others–it is necessary to read all labels carefully before using these products.

IODINES

BRAND NAMES: Vanodine, Betadyne, Povidone, Scrubodyne

Iodine solutions are frequently used as antiseptics for cleaning wounds and skin. Most iodine-containing disinfectants also contain a detergent, and are called “iodophors”. Medium cost.

ADVANTAGES

Limited vapor production; not usually affected by hard water; long shelf life; works well in hot or cold water; are effective against many bacteria, some fungi and viruses.

DISADVANTAGES

Most require full-strength use which increases cost per use; may stain surfaces and tissues brown; toxic if ingested (may cause iodine overdose); may dry and crack skin; corrosive to metal surfaces with prolonged exposure; easily deactivated by contact with organic debris; is NOT effective against hydrophylic viruses such as polyoma and PFBD (Psittacine Beak and Feather Disease); not effective against all strains of Pseudomonas bacteria.

PHENOLS

BRAND NAMES: Lysol, One Stroke Environ, O-Syl

Phenols are produced by coal distillation. Sodium orthophenol is the active ingredient in most phenol disinfectants. Phenols are effective against many bacteria, including Pseudomonas and mycobacteria, fungi and some viruses. They may not work well in the presence of organic material. Some phenols are inexpensive, and are easily available at the grocery store.

ADVANTAGES

Kills many pathogens, including bacteria such as Salmonella and Pseudomonas, mycobacteria, fungi and lipophilic viruses; effective even in hard water; doesn’t stain surfaces or leave residual odors, low cost; easy to rinse off objects

DISADVANTAGES

Toxic to many tissues including skin, eyes, and respiratory tract; VERY toxic to cats and reptiles; may not work well if organic debris is present; not effective against bacterial spores or hydrophilic viruses; must be used with adequate ventilation; must be rinsed off cleaned surfaces before allowing birds contact with them

QUATERNARY AMMONIUM COMPOUNDS

BRAND NAMES: Roccal-D, Quintacide, Parvosol, Hitor, Omega, Barquat, Merquat, Cetylcide

“Quats” are a large class of disinfectants which add organic compounds to ammonia. Many quats also function as a detergent, and help remove organic debris from objects. The presence of organic debris, however, may deactivate the disinfectant in the quat compound. They are not recommended for use on objects that will be in direct contact with birds because they are very difficult to rinse off completely, and residue can cause respiratory paralysis and death! May be diluted for lower cost per use, but initial purchase cost may be expensive. Quats are effective against many types of bacteria, some viruses, and chlamydia; they are not effective against spores, mycobacteria or fungi, Pseudomonas, and hydrophylic viruses such as Polyoma or PFBD.

ADVANTAGES

May be used at very dilute solutions, allowing for lower cost per use; contains detergent for action against organic debris; pleasant scent in most forms; good disinfectant against many bacteria, a few viruses, and chlamydia

DISADVANTAGES

Not effective against bacterial spores, Pseudomonas, fungi or mycobacteria, hydrophylic viruses; high levels of organic debris may inactivate the product; hard water may inactivate the quat product; may leave slimy residue on objects which won’t rinse off; ingestion and inhalation of products or residue may cause respiratory paralysis and even death.

WOOD TAR DISTILLATES

BRAND NAMES: Pine-Sol, Hexol

Wood tar distillates are a by-product of the lumber industry. They include such products as creosotes, turpentine and pine oils. Pine oils are the only member of this group with any disinfectant applications, and only when mixed with soap. They are very safe, but have very low levels of effectiveness against any pathogens. Very inexpensive, and available at many department, hardware and grocery stores.

ADVANTAGES

Easily available; low cost; pleasant fragrance; low toxicity; detergent ingredients make them good cleaning products for removing organic debris

DISADVANTAGES

Very poor effectiveness against any pathogens; hard to rinse off surfaces, may leave floors slick.

IN CONCLUSION

When you do require a disinfectant in your aviary or home:

  • Using hot water usually increases the effectiveness of cleaning agents.
  • Washing items thoroughly of all organic debris (food, feces, dirt) will assist the activity of any disinfectant you choose. Be sure to rinse well after washing.
  • Read ALL instructions thoroughly before beginning to disinfect an object.

Use the best possible disinfectant for your specific situation–read about which pathogens it will kill, how difficult it is to use, and any special requirements. Don’t buy a bottle of a disinfectant if you won’t be able to use it properly for some reason (does it require protective clothing you don’t have? Will it create toxic fumes in a room you cannot ventilate?) . Take all required proper precautions before starting a disinfecting project.

The use of disinfectants is only one step in taking good care of the birds who share your life and home. Never rely on a disinfectant to take care of a disease problem after it’s gotten started–do your best to prevent the problems from getting a foothold beforehand!

For a general overview on the needs and uses of disinefectants, read the accompanying article An Overview of Disinfectants and Their Uses.

REFERENCES

Clipsham, R., Environmental Preventive Medicine, in proceedings of MARE seminars, 1992

Ritchie, B.; Avian Viruses, Function and Control, 1995; pp 114-118

Vaughn, S, Disinfectants and their Use, in proceedings of MARE seminars, 1993

Springthorpe, V.S. and Sattar S.A; Chemical Disinfection of Virus-Contaminated Surfaces; Critical Reviews in

Environmental Control, Vol. XX, No. 3, 1990