Quantitative carrier test for the evaluation of virucidal activity for instruments used in the medical area - Test method and requirements (phase 2, step 2) (NF EN 17111: 2018).
Test not accredited yet by ENAC (Spanish National Accreditation Entity).
Test with the Certificate of Good Laboratory Practices (GLPs).
This test applies to products that are used in the medical area to disinfect instruments by immersion. The European standard EN 17111 specifies a support test to establish whether a chemical disinfectant for use in instruments (surgical instruments, anesthesia material, endoscopes, etc.) has a virucidal activity in the fields described by the standard: 1) virucidal activity against enveloped viruses in pre-cleaning products, with a combination of cleaner and disinfectant, 2) virucidal activity for disinfection of instruments at temperatures < 40°C, and 3) virucidal activity for disinfection of instruments at temperatures ≥ 40°C.
In this test, a suspension of test virus in a solution of interfering substances is spread on a glass support. After drying, the support is immersed in a sample of the product as received and/or diluted and kept at the specified temperatures and contact time. At the end of this contact time, the numbers of surviving viruses in each sample are determined and the reduction is calculated by comparing the results of the product with those of a water control. For a product to be considered active, it must demonstrate at least a 4 log reduction in the titer of the test viruses.
The test conditions indicated by the standard, according to the activity to be claimed, are: 1) activity against enveloped viruses with pre-cleaning products, with a combination of cleaner/disinfectant: the test is carried out using the Vaccinia virus, a temperature of 20°C, a contact time not exceeding 60 minutes, and clean (0.3 g/L bovine albumin) or dirty conditions (3 g/L bovine albumin + 3 mL of erythrocytes); 2) virucidal activity for the disinfection of instruments at temperatures <40 ° C: the test is carried out with Adenovirus type 5 and Murine Norovirus viruses, a temperature between 20°C and < 40°C, a contact time not exceeding 60 minutes, and clean conditions (0.3 g/L bovine albumin) or dirty (3 g/L bovine albumin + 3 mL of erythrocytes); and 3) virucidal activity for the disinfection of instruments at temperatures ≥ 40°C: using Murine Parvovirus as the test virus, a temperature between 40°C and 70°C, a contact time not exceeding 60 minutes, and conditions clean (0.3 g/L bovine albumin) or dirty (3 g/L bovine albumin + 3 mL of erythrocytes).
Virucidal activity according to EN 17111 is carried out only with viruses with limited spectrum virucidal activity according to suspension standard EN 14476 (Adenovirus type 5 and murine Norovirus). This is because the Poliovirus cannot be used in tests on supports because it does not adequately resist drying. However, the EN 17111 standard indicates that to indicate that a product has general virucidal activity, the product must meet the requirements of the EN 14476 standard with Poliovirus, Adenovirus and murine Norovirus, and of the EN 16777 standard Adenovirus and Murine Norovirus.