Persistent SARS Infections, Malignant Evolution, and Pertinent Hindrance of Tumors by Vaccination

The three coronavirus variant infections which evolve onto severe respiratory syndromes, have occasionally been related with persistence. The viral RNA might be affected singly, or else, by new, often systemic, and neurological symptoms that might represent the only disease manifestations. At times, it may associate with variable immunity. A persistent COVID-19 may initiate a “long COVID” episode. It has been hypothesized that, pending a protracted follow-up, the persistence of the SARS-CoV-2 might progress into a cancer: TMPRSS2 gene may develop into a prostatic cancer, while ground glass lung opacities may lead to a lung cancer. In contrast, vaccines may impede the development of a malignancy. Among these, the BCG vaccine predominates, together with the MMR vaccine; mumps and measles in the latter, being possibly responsible for a tumor handicap. It is too early to discern a similar role for COVID-19 with anti-SARS-CoV-2 vaccines, as they may relate to cancer.