Virox Animal Health Blog

In my last blog, I spoke about pathogens and the hierarchy of susceptibility, also known as the order of microorganisms and their susceptibility to disinfectants based on where they are on the scale. But it occurred to me after, that this doesn’t explain what to do with emerging or “new” pathogens. This leads me to ask what we can expect of a disinfectant when a new pathogen emerges out of left field and we might not know much about it yet.

Prior to the updated emerging pathogen guidance, disinfectant registrants were forced to test each and every virus they wanted to make a claim against.  This of course causes significant issues when new viruses “pop up” leading to significant outbreaks such as Ebola, new strains of canine influenza or Porcine Endemic Diarrhea virus (PEDv).  When an outbreak erupts as a result of a new virus, it can take a considerable amount of time to identify what the new virus is (e.g. think back to SARS when we had no clue what the virus was).  If we have not yet identified the virus, a disinfectant manufacturer cannot have their product tested against it.  Even if the virus has been identified it can be months or years before a method is developed that meets the EPA’s requirements to allow for label claims.

There was an excellent article written in 2007 by Dr. Syed Sattar, a world renowned microbiologist who recommended “In the case of new and emerging viruses still awaiting culture and full characterization, it is proposed that any official recommendations for disinfectant use be based on the well-established hierarchy of susceptibility to such chemicals as related to virus particle size and structure”.  Several countries including Canada, Australia and several in Europe have implemented a “General Virucide Claim” whereby a disinfectant, if it has shown efficacy against one or more viruses such as poliovirus, adenovirus or parvovirus, allows a product to state that it has the ability to kill both enveloped and non-enveloped viruses.  This claim can then be applied in the event of an outbreak by a virus of unknown origin. 

Now, The EPA’s Emerging Pathogen Guidance has been updated to allow for some wiggle room. Under the new guidance document, the EPA outlines to registrants the viral hierarchy that can be used to identify effective disinfectant products for the use against emerging pathogens. In addition to this, it now permits registrants to make limited claims of their product’s efficacy against such pathogens. According to the EPA, the intention of the new guidance applies only to emerging viruses and is intended to allow for a voluntary, two stage process that involves product label amendments and modified terms of registration.  Unlike the countries noted above where there is a blanket General Virucide Claim, the EPA has decided that this guidance may be taken for eligible products ONLY after the Centers for Disease Control and Prevention or the World Organization for Animal Health (OIE) has identified an emerging pathogen (new or re-emerging) where environmental surface disinfection has been recommended to help control its spread. 

According to the EPA, in order to be eligible to meet the Emerging Pathogen Guidance, the disinfectant product must meet the following 2 criteria. 

1. The product is an EPA-registered, hospital/healthcare or broad-spectrum disinfectant with directions for use on hard, porous or non-porous surfaces
2. The currently accepted product label (from an EPA registered product as described above) should have disinfectant efficacy claims against at least one of the following viral pathogen groupings:
1. A product should be approved by EPA to inactivate at least one large or one small non-enveloped virus to be eligible for use against an enveloped emerging viral pathogen.
2. A product should be approved by EPA to inactivate at least one small, non-enveloped virus to be eligible for use against a large, non-enveloped emerging viral pathogen.
3. A product should be approved by EPA to inactivate at least two small, non-enveloped viruses to be eligible for use against a small, non-enveloped emerging viral pathogen. 

For example, this means that if the virus associated with the outbreak is caused by a small, non-enveloped virus, the disinfectant must already be registered and proven effective against two small, non-enveloped viruses.  If the product only has claims against enveloped viruses it will not qualify. 

All this information provides further evidence that strength does not always come in numbers. And at Virox Animal Health, we pride ourselves on testing our Accelerated Hydrogen Peroxide® (AHP®) products against the hard to kill pathogens and the relevant pathogens within your facility.

P.S…we have many small, non-enveloped virus claims so we have you covered!!!