Is the BCG vaccine a useful tool against COVID-19?

The Bacillus Calmette-Guérin (BCG) vaccine has been used since 1921 initially for protection against tuberculosis. BCG acts through stimulation of cell-mediated adaptive immunity with activation of the Th1 cells and production of interferon gamma. Additionally, it is able to stimulate the immune system in a nonspecific manner, which results in effectiveness of the BCG against non-mycobacterial infections and in some malignant, autoimmune, and inflammatory diseases.

Antimicrobial activity and antibiotic susceptibility of and spp. intended for use as starter and probiotic cultures.

Antimicrobial activity and antibiotic susceptibility were tested for 23 and three strains isolated from different ecological niches. Agar-well diffusion method was used to test the antagonistic effect (against , , and ) of acid and neutralized (pH 5.5) lyophilized concentrated supernatants (cell-free supernatant; CFS) and whey (cell-free whey fractions; CFW) from de Man-Rogosa-Sharpe/trypticase-phytone-yeast broth and skim milk.