A recently modified World Health Organization (WHO) Formulation I was examined as 80 percent and 97 percent solutions against poliovirus type 1, adenovirus type 5 and murine norovirus according to the new European Norm prEN 14476:2011. In a previous study the unmodified WHO Formulation I had failed to demonstrate a sufficient activity against poliovirus type 1 according to the European Norm EN 14476-2007 whereas a sufficient activity was seen with adenovirus and norovirus.
The researchers found that the modified WHO Formulation I demonstrated a virucidal activity against all three test viruses of the European Norm prEN 14476:2011 under clean conditions. This was achieved as 80 percent solution against adeno- and norovirus within 30 seconds and as 97 percent solution against poliovirus within 60 seconds. Testing the unmodified WHO Formulation I against poliovirus type 1 in the 97 percent ass percenty of the European Norm prEN 14476:2011 an identical activity could be demonstrated. When comparing the 80 percent and the 97 percent assay of the European Norm prEN 14476:2011 the modified WHO Formulation I as 80 percent solution was active against adenovirus type 5 within 30 seconds whereas the 97 percent solution failed within 2 minutes exposure time.
The researchers conclude that the technical possibility in the new European Norm prEN 14476:2011 allows testing a ready-to-use disinfectant as 97 percent solution and is responsible for the new virucidal claim of the modified WHO Formulation I. In contrast to the improvements with poliovirus type 1 the activity against adenovirus type 5 decreased when increasing the test concentration from 80 percent to 97 percent. Their research was published in Antimicrobial Resistance and Infection Control.
Steinmann J, Becker B, Bischoff B, Magulski T, Steinmann J and Steinmann E. Virucidal activity of Formulation I of the World Health Organization's alcohol-based handrubs: impact of changes in key ingredient levels and test parameters. Antimicrobial Resistance and Infection Control 2013, 2:34 doi:10.1186/2047-2994-2-34