SARS-COV 2, like HIV, induces an NK, CD4+, CD8+-based immune-depression proportional to the COVID-19 severity and immune-anergy after the seventh day from the beginning of clinical symptoms, which is the principal cause of fatalities in older people affected by atherosclerosis-based comorbidities. Since the 2003 SARS-COV pandemic, this clinical evidence did not orient WHO and anti-COVID 19 scientific committees to a natural innate and adaptive active immunity boosting-based primary and secondary prevention and immune-therapy in anergy. It represents a guilty omission, only orienting countries to mass vaccination with experimental vaccines of limited validity with unknown but clinical and scientific evidence of short-term and probable long-term adverse effects. Beta-glucans, structural polysaccharides present in Baker's Yeast, cereals, algae, or exo-polysaccharides in the wall of mushrooms or fungi like Ganoderma Lucidum (Reishi), Grifola Frondosa (Maitake), and Lentinula Edodes (Shitake), Coriolus Versicolor, in evolution responsible of the defense from massive pandemics, are powerful innate and adaptive immunity boosters. Extensively studied in cancer prevention and therapy, they boost innate humoral immunity, neutralize immimmunosuppression, and induce an active humoral adaptive one, representing an easy, cheap, formidable weapon against SARS-COV 2 accessible for all worldwide, for primary and secondary prevention, and therapy, at zero costs, inducing the pandemic shutdown, and cross prevention against cancer and other communicable diseases.