SARS-Cov 2 infection and anti-tuberculosis immunity: temporal association or real protective role?

Abstract

Introduction: According to the literature consulted to date, there is epidemiological heterogeneity of covid 19 between countries depending on their vaccination policy, in particular BCG vaccination. These findings have led to several hypotheses, including the protective role of immunity induced by the BCG tuberculosis vaccine against Covid-19 infection. The immunity induced by the BCG vaccine significantly increases the secretion of pro-inflammatory cytokines, in particular IL-1B, which has been shown to play an essential role in antiviral immunity. This cross-immunity, although not specific, if highlighted, is a real providence that must be taken advantage of in the face of this pandemic. The main objective of this study is to rule out or confirm that anti-tuberculosis immunity protects against SARS-COV 2 in our context. Materiel and methods: Two groups will be compared: cases infected with the virus and controls who have never been infected with the virus. Both case and control groups will undergo a tuberculin skin test: the intra dermal tuberculin reaction (IDR). Results: We found that our control group had a high IDR immunity value, with an IDR tuberculin positive percentage of 67.2%. This suggests that immunity to IDR is a protective factor against coronavirus disease. Conclusion: The hypothesis of nonspecific anti-tuberculosis protection deserves further verification studies; it would have large positive repercussions for developing countries.