Isolated single organisms do not belong in nature as treatment of ailments. And certainly not those organisms that have been genetically manipulated in order to serve the higher purpose of selfish commercial or academic righteousness. Short from doing this, there is no other major, single, powerful, alternative option for genetic manipulation. We can just let our multitudes of tiny organisms do their ecological job. We do not need to risk epidemics of new and really unknown living things.
Sincerity abounds with hope.
Ye shall keep My statutes. Thou shalt not let thy cattle breed with a diverse kind. V. Bianciotto, et al. De Biologia Vegetale dell niversita di Torino. A.H. Fitter and J. Garbaye.