Does Your Disinfectant Work in Winter?
Increasing the contact time (more than 10 minutes) could help, however; the extended contact time is only effective if the surface remains wet, which might not be possible in freezing temperatures. Increasing concentration may speed up the rate of kill but comes at a risk of increased toxicity and higher cost in use.
Conversely, Virkon™ S maintains effective activity against disease-causing organisms at 5°C/41°F, eliminating the need to increase contact time or concentration of the disinfectant solution. Virkon S is an oxidative chemistry and therefore is not impacted by cold temperature. Numerous independent studies show Virkon S is just as effective at cold temperature as it is at room temperature.
Fall and winter pose new challenges as well as opportunities to enhance biosecurity protocols on the farm.
Environmental temperature can play a large role in the efficacy of a disinfectant. The ability of a disinfectant to work well at low temperatures contributes to the value of its use on a daily basis. It is well documented that the efficacy of some disinfectant chemistries, such as aldehydes (glutaraldehyde) as well as quaternary ammonia compounds can decrease as temperatures decrease within the environment. This can result in the disinfectant solution becoming ineffective against the disease-causing organisms of concern.
In order to compensate for any loss of efficacy under cold conditions, the corrective action would be to increase the contact time of the solution on the surface or, in some circumstances, increase the concentration of the disinfectant itself in order to achieve similar results.
Virkon S is Effective at Cold Temperatures (5°C/41°F), Against the Following Viruses
- Avian Adenovirus Type 2
- Avian Infectious Bronchitis
- Avian Influenza virus
- Marek’s Disease Virus
- PEDv
- PRRS
- Porcine Rotavirus
Virkon S Independently Proven Efficacy
| Pathogen | Concentration | Contact Time | Temperature |
| Avian Adenovirus Type 2 | 1:200 | 10 min | 5°C/41°F |
| Avian Infectious Bronchitis | 1:200 | 10 min | 5°C/41°F |
| Avian Infectious Bronchitis | 1:200 | 1 min | 5°C/41°F |
| Avian Influenza | 1:200 | 10 min | 5°C/41°F |
| Avian Influenza | 1:200 | 1 min | 5°C/41°F |
| Avian Infectious Laryngotracheitis | 1:200 | 10 min | 5°C/41°F |
| Marek’s Disease Virus | 1:200 | 10 min | 5°C/41°F |
| PEDv | 1:200 | 10 min | 5°C/41°F |
| PEDv | 1:200 | 1 min | 5°C/41°F |
| PEDv | 1:600 | 10 min | 5°C/41°F |
| PRRS | 1:600 | 10 min | 5°C/41°F |
| Porcine Rotavirus | 1:600 | 10 min | 5°C/41°F |
Chemical Reactions in Cold Temperatures
In order to understand how low temperatures can negatively affect the efficacy of certain disinfectants, we must understand the chemical reaction, which takes place. Aldehydes mechanism of disinfection is based on the inhibition through polymerization or gelation of the membrane of the microbe. The rate of this reaction is dependent on the ability of the protein coming into contact with the antimicrobial. This reaction rate decreases with decreasing temperature, which may ultimately affect the efficacy of the disinfectant.
Data from a glutaraldehyde manufacturer shows the dramatic decrease in efficacy that temperature has on glutaraldehyde. A 4-log reduction is required for disinfection. Their data shows that in order to achieve a 4-log reduction of E.coli at 22°C (72°F) a contact time of 60 minutes is required.
Quaternary ammonia compounds disinfect based on denaturation (disentanglement or unraveling) of the protein shell of the microbe. The denaturation of the protein is heavily based on mobility and is highly dependent on temperature. As temperature decreases, it affects the denaturation speed and therefore may decrease the efficacy of quat-based disinfectants.
Oxidative Chemistry
The mechanism of oxidizing disinfectants is based on radical-ion reactions. The oxidation of the cell is a continuous reaction, which creates new radicals and ions independent of temperature. The radical ions break up the protein found inside of the membrane of the microbe. Cold temperatures tend to not interfere with this reaction and therefore, the efficacy remains relatively stable.
Therefore, oxidizing compounds can be used during warm or cold weather conditions without showing a large decrease in reaction rate or efficacy of the disinfectant. Virkon S maintains effective activity against disease-causing organisms at 5°C/41°F and below, eliminating the need to increase contact time (10 minutes) or concentration of the disinfectant solution. Ten minutes is all it takes to prevent disease-causing organisms from affecting your live production, in cold and warm weather conditions.
Effect at Cold Temperature – Glutaraldehyde
During Cold Temperatures
- 4ºC/39ºF efficacy is 2.8 Log Reduction, 60 minutes
- 22ºC/72ºF efficacy for a 4 Log Reduction, 60 minutes
During cold temperatures, this results in longer contact times or higher concentration (than originally stated on the label).
Note: The information contained in this publication is current as of November 2020. Please contact LANXESS Corporation to determine if this publication has been revised.
Content From: Lanxess Corporation