For IVD Medical Devices for Infectious Diseases e.g. Covid-19 are these classified in IVDR as high-risk Class D?
In which class is some IVD for COVID-19 depends on what type of the test it is. There are three main types of detection assays relevant for COVID-19 diagnostic testing and screening:
1. Nucleic acid tests that detect the presence of viral RNA.
2. Antigen tests that detect the presence of a viral antigen, typically part of a surface protein.
3. Antibody tests detect the presence of antibodies generated against SARS-CoV-2; like immunosorbent assays (ELISA), chemiluminescence assays (CLIA) and lateral flow assays (LFA).
According to IVD Directive 98/79/EC Article 9, on conformity assessment procedures, for COVID-19 diagnostic devices that are not intended for use as self-tests, the manufacturer shall, in order to affix the CE marking, draw up the EC declaration of conformity required before placing the devices on the market. This is a self-declaration procedure based on satisfying essential safety and performance requirements listed in the Directive and specifications of the device performance characteristics, stated by the manufacturer. In case of self-tests, the involvement of a third-party conformity assessment body is necessary.
European Commission has published a document which proposes a tentative definition of COVID-19 diagnostic test performance criteria (analytical sensitivity, analytical specificity, clinical sensitivity, and clinical specificity) - Current performance of COVID-19 test methods and devices and proposed performance criteria - Working document of Commission services https://ec.europa.eu/docsroom/documents/40805
European Commission also published a searchable database. The objective of the JRC COVID-19 In Vitro Diagnostic Devices and Test Methods Database is to collect in a single place all publicly available information on the performance of CE-marked in vitro diagnostic medical devices (IVDs) as well as in-house laboratory-developed devices and related test methods for COVID-19. - COVID-19 In Vitro Diagnostic Devices and Test Methods Database https://covid-19-diagnostics.jrc.ec.europa.eu/
And must the CE Mark have the NB 4 digit Number next to the CE Mark?
This depends again on what kind of diagnostic test it is. If it is self-test than it needs NB 4 digit numbers, if it is not then there is a self-declaration and there is no need for the NB 4 digit numbers next tot he CE mark.