Standard Test Method to Assess the Activity of Microbicides against Viruses in Suspension (ASTM E1052-20 Standard).
Test accredited by ENAC (Spanish National Accreditation Entity).
This test method is intended to demonstrate the virucidal activity of test substances with virus in suspension. To perform the test, one part of the virus suspension is added to nine parts of the test substance, the mixture held at the desired temperature (usually 22±2ºC) for the required contact time and then assayed for viable virus in an appropriate cell culture. The level of viral inactivation is calculated comparing the viral titre with those obtained from the control, where one part of the virus suspension is added to nine parts of buffer harmless to the virus. A load of interfering substance such as fetal bovine serum at a final concentration of 5% or a mixture of tryptone, BSA and mucin can be added to the test. The product should be tested at least three concentrations including one in the active range and one in the non-active range (these last two concentrations are chosen by the laboratory that performs the test since they correspond to the positive and negative controls, respectively). Cell culture, cytotoxicity, and virus susceptibility controls must also be included in each test. To carry out a complete and more rigorous test in our laboratory, the controls indicated by the ASTM E1052 standard and by the EN 14476 standard are used. To consider the virucidal product, a logarithmic reduction of 4 in the infectivity must be demonstrated.
The ASTM E1052 standard does not establish a mandatory test virus but rather suggests the following test viruses: Adenovirus type 2 or type 5, Canine Parvovirus, Cytomegalovirus, Feline Calicivirus, Hepatitis A virus, Herpes simplex, Murine Norovirus, Respiratory Syncytial virus, Rhinovirus, Rotavirus or Vaccinia.