Bacillus Calmette-Guérin (B.C.G.)

BCG and SARS-CoV-2—What Have We Learned?

“…Mycobacterium bovis (bovine mycobacteria), on which the BCG vaccine is based, after 11 years of attenuation (from 1908 to 1919), was deprived of its pathogenicity, which allowed it to be used for the production of an antimycobacterial vaccine [ 11 , 12 , 13 , 14 , 15 , 16 ]. By 1928, 114,000 children had been vaccinated [ 11 ], and although the studies at that time could hardly be assumed to meet the standards of double-blind placebo-controlled trials, the vaccine was considered safe and effective in children [ 17 , 18 , 19 , 20 , 21 , 22 ]. Soon, vaccination was implemented throughout Europe, and after World War II, the WHO recommended expanding the vaccination campaign beyond Europe [ 23 , 24 , 25 ].…”

“…An immune training mechanism is responsible for this effect, at least in part, in which the epigenetic reprogramming of innate immune cells leads to the increased production of inflammatory cytokines and, consequently, a stronger immune response [ 15 ]. Kurthkoti et al [ 22 ] hypothesized that BCG vaccination provides heterologous immunity by enhancing the innate and adaptive immune response to COVID-19. They concluded that it is possible that prior BCG vaccination may result in higher levels of IFN-γ, which may prevent T-cell migration to the lungs and reduce tissue damage [ 97 ].…”

BCG: who were Calmette and Guerin?

“…He was buried at Chatellerault, near Poitiers, where a town street, a hospital, and a lycee now carry his name. [3][4] The birth of BCG When Calmette was appointed director of the Pasteur Institute at Lille in 1896, the main public health problem with which he had to contend was tuberculosis. The death rate for tuberculosis in Lille was 300 per 100 000.…”

The Calmette-Guérin Vaccine

“…It may be true, as some claim, that the use of BCG carries danger of infection to the child. Especially in view of the dissociation into two types, one virulent for guinea pigs and the other not, demonstrated by Petroff,5 we are obliged to hold that the safety of the procedure has not been proved, and for the present must recommend caution in the use of the vaccine while hoping for the best.…”