New cancer treatment believed to induce immunity

Top of the range cancer treatments often rehabilitate the degenerative cells. After being cleansed they are injected back into the patient’s system, believed to induce immunity. With regard to covid, will endeavouring to stay clean, but continuing to be around a virus such as corona be effective in building up immunity? Diet and cleansers such as antiseptics would be paramount in beating the virus. Sugar is a food for bacterias, including viruses.