What Is Virucidal Efficacy?

There are over 8 million forms of life discovered to date on our planet.  People used to think that all living organisms are either animal or plant.  With the development of science, people have come to the realization that life forms are far more diversified.  The current phylogeny puts all living organisms into three domains: Eukaryota (animals, plants, fungi and protists), Bacteria and Archaea.  All these organisms have DNA as their genetic material.

What about Viruses?

Virus, a biologically important type of entity, does not fit into any of the above domains.  Similar to bacteria, viruses cannot be seen by naked eyes so they are also “micro-organisms”.  But it shall be noted that viruses are not bacteria: they do not have a cell wall and they cannot reproduce by themselves.  All viruses may replicate only inside a host.  Additionally, viruses are much smaller than bacteria (by 1-2 orders of magnitude).  And interestingly enough, while some viruses use DNA as the genetic material, others use RNA.

Virucidal Efficacy Defined

When in contact with a host, a viral particle may bind to the host, enter it and begin replication.  This infection may lead to illness if the virus is pathogenic.  Therefore, there’s an obvious medical benefit if one can apply a chemical or a process to disrupt the viral particles to make them non-infectious.  These chemicals or treatments are usually termed “vc” or “virucidal”.  Commonly used chemical virucidal agents include bleach, alcohols, quats, hydrogen peroxide, aldehydes, acids, alkalines and phenolics, etc. Common physical processes include UV irradiation, heat and gamma irradiation, etc.  They vary in their efficacies: speed, safety, longevity and easiness of use.  The exact efficacy must be determined scientifically via laboratory testing; and the efficacy of these virucidal agents are termed “virucidal efficacy”.