Jenner’s 1796 cowpox vaccine generated lymphocytes to attack the smallpox pathogen. According to New Scientist 21/03 vaccine development takes 5 years.
In the meantime, Louis Pasteur’s (1822-1895) theory is to prevent and treat disease by killing germs. Alternatively, Antoine Béchamp (1816 -1908) proposed his ‘cellular theory’ or ‘biological terrain’, based on fostering good health. Principia Scientific on April 7th, 2020 updated respect for his theory.
Towards the end of his life, Pasteur renounced his germ theory and admitted that Bechamp was right all along.
All three theories are in use against COVID-19. A vaccine is being attempted, Pasteur’s method is trying to prevent spreading, transmission and inhalation of germs, using distance, barriers and disinfectants. Bechamp’s method strengthens immune system responses with diet, hygiene, fresh air and exercise. The three are complements but reducing exercise and fresh air would be contrary to Bechamp’s and anything enabling germ access would oppose Pasteur’s.
Public health advice has elements of all three approaches. Whether a person follows ‘germ theory’, or ‘vaccination’, or ‘cellular theory’, empirical validation would relate it to the health outturn.