Dr Robert Gallo, of the University of Maryland School of Medicine, who is credited as a co-discoverer of HIV, believes the oral polio vaccine (OPV) can be repurposed as a tool in the fight against Covid-19. In an interview with journalist and author Walter Isaacson for veteran American journalist Christiane Amanpour’s show on PBS, Dr Gallo said that the vaccine has been documented to provide protection against a number of viral and bacterial infections other than poliomyelitis, including flu.
With a SARS CoV-2 vaccine likely to take months to develop and prove efficient and safe, Dr Gallo says existing live attenuated (weakened antigen) vaccines that have proven to be safe through clinical evaluation can be used; the renowned researcher though batted specifically for OPV in the interview and in an opinion article in USA Today co-authored with Dr Konstantin Chumakov of the US Food and Drugs Administration (who also serves as the director of the Center for Excellence of the Global Virus Network that Dr Gallo co-founded). Chumakov and Gallo say, apart from inducing production of antibodies against the poliovirus, OPV activates other aspects of the immune system, including innate immunity that makes people resistant to a clutch of viral and bacterial infections. In clinical trials conducted in the 1970s during the outbreak of seasonal influenza, OPV was found to have shielded more people from seasonal influenza than some flu vaccines do.
Dr Gallo and Dr Chumakov briefly talk about research showing non-specific protection from vaccines such as BCG, measles and other live attenuated (weakened) vaccines. In his interview, Dr Gallo makes it clear that he isn’t certain of the duration for which the innate immunity from OPV may offer protection against SARS CoV-2, but estimated that it could do so for 1-2 months. While SARS CoV-2 and poliovirus are both RNA virus, Dr Gallo said that he wasn’t sure if this could ply a role in OPV conferring temporary immunity against SARS CoV-2. He spoke of the possibility of a double-blind trial of OPV as a response measure to SARS CoV-2 kicking off soon at two locations, Mt Sinai Hospital, New York, and the Institute of Human Virology at University of Maryland.
