The question of illness and suffering involves the entirety of the work of Jonas and not only his works on applied ethics. As the analysis of the context of this question shows, Jonas meets it on several fronts: there is the history of freedom, illness and suffering, biological history, and again the physiological history of the meaning of suffering. The general philosophical lesson seems to be the following: while preserving themselves from the errors of existentialism, it is time for human beings to recover the virtue of endurance, which is the specific lot of finite time, suffering and mortal existence.
Dupuis, M. (2002). Le fardeau et la grâce de l’endurance. Revue Philosophique de Louvain, 100(3), 418-436. https://doi.org/10.2143/RPL.100.3.690 (Original work published 2002)