Survival time of organisms in the laboratory under suboptimal conditions?

The Genetic Engineering Safety Ordinance (GenTSV) lists the general criteria for the risk assessment of (micro)organisms during genetic engineering work in Annex 1, point 1. In addition to pathogenicity, infectious dose and transmission routes, the criterion of resistance or tenacity is also listed there. The term tenacity describes the ability of an organism to survive even under less than optimal conditions and to maintain its ability to reproduce and infect. For unicellular organisms, bacteria and viruses, the relative survival time outside their natural habitat or host increases with their degree of tenacity. Depending on the organism, factors such as temperature, nutrient supply or water content in the surrounding environment determine this time interval. In the context of genetic engineering work, where the formation of contaminated aerosols can occur, or in experiments with airborne, genetically modified organisms (GMOs), their tenacity is an important criterion in determining safety and decontamination procedures. The question often arises as to how long, for example, a released (genetically modified) organism remains viable or infectious on an inanimate surface in the work area. A wealth of experimental data and published studies already exist on this topic, although most of them were obtained using wild-type organisms (summarized, among others, in Wißmann et al., Microorganisms, 2021). For example, it has been shown that non-enveloped viruses (e.g., enteroviruses and parvoviruses) have high tenacity, whereas enveloped viruses (e.g., retroviruses) are inactivated relatively quickly on inanimate surfaces outside the host. Bacteria, especially those that form persistent forms, generally have a higher tenacity than viruses. Whether surfaces, equipment, or other materials (e.g., filter cassettes) in a genetic engineering facility can be considered GMO-free after a certain "cooling-off period," taking into account the individual tenacity of the organisms being processed, should always be agreed upon in advance with the responsible supervisory authority.