The book describes medical events, health events, social events, environmental events in the period from January 2020 to May 2023. Viruses are described in the book, bacteria, microorganisms. Disinfection methods, methods of sanitation, disinfestation methods. A method for eradicating the Sars-CoV-2 coronavirus means living in ventilated environments, doors, windows slightly open so that viruses do not enter they thicken in the air, they do not find the cells to infect and not they infect people. By opening the windows slightly, the doors, viruses dissolve in the air, capacity weakens infectious virus. Environmental factors and epidemics are closely related, every year due to the flu hundreds of millions of animals are killed by avian flu farm. A healthy nature is equivalent to non-diffusion, to the non-proliferation of pathogenic viruses and microorganisms pathogens. A healthy nature, a healthy environment plays a role protective action towards people. A healthy, unpolluted, uncontaminated nature equals face and inactivate pathogenic viruses. By putting into practice some simple rules, prescriptions and Indications reported in the book, a person, a family, groups of people they would not become infected and spread the Sars-CoV-2 virus.