What exactly are dual-use organisms?

The term "dual use" means "double purpose". It is explicitly mentioned in TRBA 200 in connection with the requirements for professional qualification according to the Biological Agents Ordinance (BioStoffV). This stipulates that when working with Biological agents of risk group 2 With a possible dual use, biosecurity aspects must be taken into account, including the prevention of loss and misuse of biological agents. Annex II of the BioStoffV, which refers to Regulation (EU) No. 2021/821, must be observed. Regulation (EU) No. 2021/821 is directly applicable in the Member States, including directly in the laboratory. For activities involving Biological agents of risk groups 3 and 4 with a dual purpose, the ABAS position paper “Biosecurity from the perspective of occupational safety – assessment of interfaces” In addition, it is required that the expertise required for the use of such dual-use biological agents must refer to specific knowledge for assessing their properties and the necessary safety measures. Appendix II to TRBA 200 lists criteria for evaluating research work. These include, among others:

−Increased virulence −Increased transmissibility −Increased tenacity −Increased resistance −Biological weapon capability −Change in host spectrum −Increased susceptibility of host organisms −Synthesis of new pathogens −Reduction of therapeutic measures −Circumvention of detection methods

If you want to know specifically which biological substances are actually dual use, only a look at the Regulation (EU) No 2021/821 and there in Part III (p. 134 pdf version). There, under the Category 1C Materials, exactly 1C351, biological substances are included under the term human and animal pathogens and toxins. There, a distinction is made between viruses, bacteria, toxins and fungi, whereby 1C353 genetic elements or GMOs are also included. 1C354 also includes the plant pathogens listed. It's worth taking a look at the list for your own organisms.