This is something many quality professionals debate about, so not everyone feels the same way about how important disinfectant rotation can be. There are some quality professionals who believe that using different disinfectants at different times will make it less likely that microorganisms will become resistant to the disinfectant and therefore continue to provide effective cleaning and sanitization of surfaces. Others believe that rotating disinfectants only complicates things without showing any benefit.
In this post, I will define and explain this principle to help you determine when this practice would be necessary. So, what is the answer to the question that rotating disinfectants helps prevent contamination in drug manufacturing?
To get the right answer to this question, first we will understand the rotation of disinfectants and why people have implemented it in pharmaceutical industries.
Switching between disinfectants regularly allows for microbes to be exposed to different modes of action and reduces the potential that a microbe will survive and adapt or develop resistance to any disinfectant. This practice is generally discussed in several industries particularly pharmaceuticals.
Theoretically, if a variety of different disinfectants containing various active ingredients and different modes of action were used in rotation or as a series of disinfectant applications, the risk for tolerant microbial populations developing could be decreased. This seems logical when you think of antibiotics and resistance, however disinfectants have a much different way of interacting with microbes than antibiotics.
The term microbial resistance to disinfectants does not have the same meaning as antibiotic resistance; however, true genetic resistance to disinfectants is relatively uncommon. What we see much more often is tolerance or reduced susceptibility to the actions of disinfectants, which are typically the result of inadequate cleaning rather than chemical adaptation. Examples of this include:
- Microbes protected by organic soils on surfaces from the disinfectant.
- Use of incorrect time periods and/or incorrect dilutions will reduce the effectiveness of the disinfectant to kill.
- Conditions resulting in inadequate mechanical action on organisms will result in failure to remove them from a surface.
In all these circumstances, switching the disinfectant is not going to resolve the underlying problems; if improper cleaning technique is the cause, the same outcome will occur regardless of which chemical is used.
- Establishing that the disinfectants that you use achieve the appropriate kill rates for the microorganisms of concern.
- Establishing what the appropriate contact times and application methods are for your disinfectants.
- Utilising environmental monitoring programs to validate the success of your programme and to identify trends.
When inspecting companies for compliance with the regulatory requirements, the focus is not on rotation, but rather on whether the programme is appropriate and supported by scientific evidence.
These reasons have nothing to do with preventing the microbial adaptation to disinfectants; rather, it relates to the appropriate use of scientific fit-for-purpose disinfectant and effective cleaning program design.
- The training of your employees becomes more complicated because they will have to learn the proper preparation ratios, contact times, and safety protocols for multiple products.
- By introducing multiple products, you are increasing the likelihood of making mistakes when measuring the dilution, determining the appropriate amount of contact time, and determining which surface to use which product.
- With every different cleaning product, you now have to validate (or show that it is effective) for every chemical being used and every application of each of these chemicals, thus making the validation process more complicated.
If your cleaning efforts maintain a microbial count within acceptable regulatory limits and have not shown any signs of contamination, additional cleaning products (rotating multiple products) may not have an effect on the overall outcome.
Rotating disinfectants should not be used to achieve microbial efficacy but rotating disinfectants does not ensure superior control of microbes. What is important for disinfectants is that are they being used appropriately and their effectiveness has been demonstrated within your environment. Changing products without providing evidence and only for a change can lead to distraction from the real causes of consistent contamination control.
When determining a disinfectant to eliminate a specific organism that are problematic in your facility, it is difficult to select a disinfectant that has a mechanism of action that will provide the highest level of risk control for that organism based on your facility's environmental impacts and risk factors. This choice should be based on scientific analysis and should not be based on a random choice.
Establishing effective disinfection practices within pharmaceutical environments depends upon the selection of an appropriate disinfectant based on fit-for-purpose, ensuring validated application and maintaining continuous performance monitoring. As a blanket strategy, the use of disinfectant rotations does not have any scientific basis. Decisions are to be made based upon data, risk assessments and regulatory expectations. The rotation of disinfectants should only occur when there is clear microbiological or operational justification.
A disciplined cleaning program will be required for cleanrooms and controlled environments. Contamination control will be more effectively achieved when the premise is based upon sound science rather than myths.
To get the right answer to this question, first we will understand the rotation of disinfectants and why people have implemented it in pharmaceutical industries.
What Does Rotation of Disinfectants Mean?
Periodic switching between various classes or chemistries of disinfectants is referred to as the rotation of disinfectants. For example, using a peracetic acid disinfectant for the first week and then changing to a quaternary ammonium and then next using a bleach solution.Switching between disinfectants regularly allows for microbes to be exposed to different modes of action and reduces the potential that a microbe will survive and adapt or develop resistance to any disinfectant. This practice is generally discussed in several industries particularly pharmaceuticals.
Where the Idea Came From
The origin of this concept is based on the fear of microbial tolerance/reduced susceptibility. Essentially, if a disinfectant is used repeatedly against a microbial organism, it has been suggested by many that the organism will become "accustomed" to that disinfectant and will be able to withstand further use of that same disinfectant after cleaning.Theoretically, if a variety of different disinfectants containing various active ingredients and different modes of action were used in rotation or as a series of disinfectant applications, the risk for tolerant microbial populations developing could be decreased. This seems logical when you think of antibiotics and resistance, however disinfectants have a much different way of interacting with microbes than antibiotics.
What the Science Says
In evaluation of disinfectant effectiveness, scientists consider several variables including log reduction, time of application, organic load on surface, surface type and types of microbes present. All of these variables determine if a disinfectant can achieve required kill rates in actual user application.The term microbial resistance to disinfectants does not have the same meaning as antibiotic resistance; however, true genetic resistance to disinfectants is relatively uncommon. What we see much more often is tolerance or reduced susceptibility to the actions of disinfectants, which are typically the result of inadequate cleaning rather than chemical adaptation. Examples of this include:
- Microbes protected by organic soils on surfaces from the disinfectant.
- Use of incorrect time periods and/or incorrect dilutions will reduce the effectiveness of the disinfectant to kill.
- Conditions resulting in inadequate mechanical action on organisms will result in failure to remove them from a surface.
In all these circumstances, switching the disinfectant is not going to resolve the underlying problems; if improper cleaning technique is the cause, the same outcome will occur regardless of which chemical is used.
Regulatory Perspective
The FDA does not have specific, written regulatory requirements regarding the schedule for rotation of disinfectants; however, it does expect to see a validated cleaning and disinfection plan that meets the criteria for controlling microbial contamination risks supported by data. This requires:- Establishing that the disinfectants that you use achieve the appropriate kill rates for the microorganisms of concern.
- Establishing what the appropriate contact times and application methods are for your disinfectants.
- Utilising environmental monitoring programs to validate the success of your programme and to identify trends.
When inspecting companies for compliance with the regulatory requirements, the focus is not on rotation, but rather on whether the programme is appropriate and supported by scientific evidence.
Reasons to Use Different Types of Disinfectants for Rotation
Using more than one type of disinfectant can be appropriate in certain situations:1. Different Pathogens or Organisms being Targeted
Some disinfectants have higher efficacy against certain organisms like hydrogen peroxide vapor is much more effective against spores than other disinfecting agents. If the organisms that are being targeted include spores then alternating the use of disinfectants with varying efficacy against these organisms is beneficial.2. Different Materials being Treated
Some disinfectants may be harmful to certain surfaces when used repeatedly while gentle cleaning agents can help to protect these surfaces. Using a gentle disinfectant on any surface that could damage from corrosive products is always a better choice.3. Operational Considerations
Various cleaning tasks may require different cleaning products due to product availability, staff preference with regard to safety or ease of use in certain areas.These reasons have nothing to do with preventing the microbial adaptation to disinfectants; rather, it relates to the appropriate use of scientific fit-for-purpose disinfectant and effective cleaning program design.
When Rotation Doesn’t Add Value
When rotation occurs for the sake of rotation, it creates unnecessary complexity with no discernible advantage.- The training of your employees becomes more complicated because they will have to learn the proper preparation ratios, contact times, and safety protocols for multiple products.
- By introducing multiple products, you are increasing the likelihood of making mistakes when measuring the dilution, determining the appropriate amount of contact time, and determining which surface to use which product.
- With every different cleaning product, you now have to validate (or show that it is effective) for every chemical being used and every application of each of these chemicals, thus making the validation process more complicated.
If your cleaning efforts maintain a microbial count within acceptable regulatory limits and have not shown any signs of contamination, additional cleaning products (rotating multiple products) may not have an effect on the overall outcome.
Best Practices for Disinfectant Use in Pharmaceuticals
If you are rotating disinfectants in your facility or remain with the same disinfectants consistently, you need to follow best practice guidelines.1. Test Disinfectants for Efficacy
Carry out efficacy testing in the facility's actual conditions such as soil load, contact time and type of surfaces.2. Validate Application Methods
Prove that you are using the appropriate methods like wipes, sprays, fogging or automated systems that are required to achieve the expected reduction of microorganisms.3. Clearly Define Contact Times
Be sure that cleaning will be followed and that staff members understand the required contact times. Shortcuts taken in this area are one of the leading causes of poor disinfection failure.4. Choose the Correct Disinfectants Based on Risk Assessment
Select disinfectants based on risks considering organisms that must be controlled, surfaces being disinfected and service workflows etc.5. Monitor and Trend Results by Ongoing Environmental Monitoring
Use ongoing environmental monitoring results to determine if your disinfectant and cleaning procedures are controlling the microorganisms in the area. If you identify a trend of increasing control failures then identify the cause instead of changing disinfectants.6. Simplify When Possible
Clarity and consistency often reduce opportunities for error. One or two good-suited disinfectants might meet all of your disinfection program requirements; Keep disinfectant programs simple.So Is the Rotation Principle True or False?
The basic answer is false as a universal rule but true in certain limited cases.Rotating disinfectants should not be used to achieve microbial efficacy but rotating disinfectants does not ensure superior control of microbes. What is important for disinfectants is that are they being used appropriately and their effectiveness has been demonstrated within your environment. Changing products without providing evidence and only for a change can lead to distraction from the real causes of consistent contamination control.
When determining a disinfectant to eliminate a specific organism that are problematic in your facility, it is difficult to select a disinfectant that has a mechanism of action that will provide the highest level of risk control for that organism based on your facility's environmental impacts and risk factors. This choice should be based on scientific analysis and should not be based on a random choice.
Establishing effective disinfection practices within pharmaceutical environments depends upon the selection of an appropriate disinfectant based on fit-for-purpose, ensuring validated application and maintaining continuous performance monitoring. As a blanket strategy, the use of disinfectant rotations does not have any scientific basis. Decisions are to be made based upon data, risk assessments and regulatory expectations. The rotation of disinfectants should only occur when there is clear microbiological or operational justification.
A disciplined cleaning program will be required for cleanrooms and controlled environments. Contamination control will be more effectively achieved when the premise is based upon sound science rather than myths.
No comments:
Post a Comment
Please don't spam. Comments having links would not be published.