The re-emergence of monkeypox, a viral zoonotic disease, into the forefront of public health has highlighted the importance of effective hygiene practices, particularly disinfection. Disinfection is essential in virus control, especially in healthcare settings, public facilities, and households. Disinfectants marketed as having virucidal efficacy against Mpox must undergo stringent tests to demonstrate their effectiveness in inactivating or destroying viruses. The following article provides an overview of methods for Mpox virucidal efficacy testing of disinfectants, regulatory standards, and why this is important for public health and safety.
Understanding Mpox and Its Transmission
Monkeypox or mpox is caused by the Mpox virus, which is part of the Orthopoxvirus genus that consists of Smallpox (Variola virus) and Vaccinia virus. People get it from direct contact with the infected body secretions, contaminated skin or surfaces and through respiratory droplets. Therefore, disinfection is crucial in controlling its spread.
Signs and symptoms include fever, rash, and lymphadenopathy; in some cases, there might be secondary infections resulting in bronchopneumonia or sepsis. The likelihood of human-to-human transmission, especially in close contact situations, therefore increased the need for effective disinfectants validated by Mpox virucidal efficacy testing for the inactivation of the virus on surfaces.
The Importance of Mpox Virucidal Efficacy Testing
The virucidal efficacy testing evaluates the anti-viral actions of disinfectants or antiseptic products. Tests are performed under controlled conditions where the virus is subjected to the action of a disinfectant, followed by the measurement of viral inactivation. Mpox virucidal efficacy testing plays an important role in identifying if a particular disinfectant has the potential to delay the spread of viral pathogens of concern, such as Mpox. These test results enable a disinfectant to be labeled effective against a virus such as Mpox.
Methodologies for Testing Virucidal Efficacy
Suspension Tests
One of the most common methods used in Mpox virucidal efficacy testing is suspension tests, whereby a virus is held in a liquid medium and subsequently mixed with test disinfectant. A neutralising agent is then added after a set time period of exposure to determine how many infectious viral particles still remain in the sample. This technique demonstrates the ability of disinfectants to interact with viruses in liquid medium such as blood or respiratory secretions.
The European standard EN 14476 serves as an internationally accepted guideline for suspension tests which specifies rules for testing disinfectants on enveloped as well as non-enveloped viruses. Any disinfectant that clears this test may be deemed effective against a range of different kinds of viruses, including Mpox.
Carrier Tests
Carrier tests, also known as surface tests, evaluate the efficacy of disinfectants on solid surfaces. In Mpox virucidal efficacy testing, the viruses are applied on solid surfaces such as glass or stainless steel and air dried. After that, a disinfectant, for a specific contact time, is used on the surface and the remaining active virus is titrated. This method is advantageous to examine the power of disinfectant on solid surfaces.
The ASTM E1053 standard is often used for carrier tests; it provides guidelines for testing the virucidal efficacy of disinfectants on surfaces. This standard is especially relevant to healthcare disinfectants.
Field Tests
Field tests are conducted to assess the efficacy of disinfectants in the natural environment. This test is essential to validate laboratory test results since environmental conditions such as humidity, temperature, and other variables may impact the effectiveness of disinfectants. For example, field tests are likely to be conducted on disinfectants used in healthcare settings, public transportation systems, or any other identifiable high-risk areas where the pathogen is likely to be found. The results of the testing will contribute to an understanding of the effectiveness of disinfectants.
Factors Influencing Mpox Virucidal Efficacy Testing
Virus Concentration and Load
The virus concentration and load on a surface or in the suspension can significantly affect the results of virucidal efficacy tests. Higher viral loads generally require more powerful disinfectants or longer contact times to be effective in the inactivation process. In the case of Mpox, understanding the typical viral loads present in different environments is crucial for selecting appropriate disinfectants validated by Mpox virucidal efficacy testing.
Contact Time
Another factor related to the Mpox virucidal efficacy testing is the time for which the disinfectant remains in contact with the virus. If the contact time is too short, the disinfectant may not fully inactivate the virus, and some of the viral particles may remain viable. For disinfectants, regulatory agencies (for example, Environment Canada or US EPA) usually provide you with a minimum contact time to fulfill the contact time needed for the disinfectant to work. For viruses, contact times may vary according to the active ingredients and the environmental conditions.
Composition of Disinfectant
The virucidal efficacy of any disinfectant mainly depends on its composition, especially on the active ingredients. Different categories of disinfectants are available that employ different classes of active ingredients such as alcohol, quaternary ammonium compounds, and chlorine compounds, all with different modes of action towards reducing viruses.
Most disinfectants that are used against enveloped viruses like Mpox contain ingredients that disrupt the viral coat, hence deactivating the virus.
Environmental Factors
The function of disinfectants is influenced by environmental factors like temperature, humidity, and the presence of organic matter. Some disinfectants may have increased virucidal activity at high temperatures while at low temperatures, their effectiveness may be reduced. The presence of organic materials (blood or body fluids) can also inhibit the effectiveness of disinfectants thus requiring higher concentrations or prolonged contact times.
For Mpox, these factors must be taken into account when testing virucidal efficacy and using disinfectants in high risk areas.
Regulatory Standards and Compliance
International Standards
Organizations such as WHO, EPA, and ECDC set out regulatory standards for virucidal efficacy testing. These guidelines define the tests for disinfectants that involve contact times and the levels of effectiveness that are acceptable to make sure they are safe and effective during usage by persons who are not specialized. The WHO has provided guidelines on disinfectants to be used in healthcare facilities emphasizing the selection of products that have been tested rigorously for their ability to kill viruses.
Labeling and Claim
Only disinfectants that fulfill the passing criteria during virucidal tests can be tagged as effective against the virus. In addition, these claims should be substantiated by strong scientific evidence and fulfill regulatory requirements based on the results obtained during Mpox virucidal efficacy testing.
Conclusion
To prevent Mpox transmission, protect susceptible populations, and safeguard public health, disinfectants need to be efficacious against this virus. Disinfectants can be validated for efficacy against Mpox through Mpox virucidal efficacy testing and checked for compliance with regulations.
At Microbe Investigations Switzerland (MIS), we offer comprehensive testing and validation services for antiviral disinfectants. Contact us today to learn more about our services.
