An Orally Administered Nonpathogenic Attenuated Vaccine Virus Can Be Used to Control SARS-CoV-2 Infection: A Complementary Plan B to COVID-19 Vaccination.

Background Coronavirus disease 2019 (COVID-19) vaccination has substantially altered the course of the pandemic, saving tens of millions of lives globally. The problem is that despite such spectacular results, vaccination alone will not be able to control the COVID-19 pandemic because of the rapid evolution of the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) even in vaccinated human populations. Therefore, the development of a post-infection, broad-based, orally administered antiviral therapy that would complement vaccination efforts is urgently needed. Methodology The so-called viral superinfection therapy (SIT) administers a nonpathogenic attenuated double-stranded RNA (dsRNA) vaccine virus drug candidate, the infectious bursal disease virus serotype R903/78 (IBDV-R903/78) that activates the interferon (IFN) genes, which are the natural, antiviral defense system of host cells. Results Here we present two cases of properly vaccinated (with BNT162b2-Pfizer) and booster-dosed COVID-19 patients with vaccine breakthrough infections whose disease duration was shortened to a few days by oral SIT. Conclusions SIT has already been demonstrated to be safe and effective against five different families of viruses, hepatitis A virus, hepatitis B virus, hepatitis C virus, SARS-CoV-2, and herpes zoster virus. The R903/78 drug candidate is simple to manufacture and easy to administer in an outpatient setting. The expected cost of SIT will be affordable even in resource-limited countries.