This idea has really caught my attention for several reasons -- mainly because the polio vaccine (OPV) is readily available (millions in stock, if not a billion worldwide) and its cost of production is reportedly around $0.15 should we need to ramp production, and we already know how to make it so it shouldn't be a problem.
The idea is interesting -- there is old data that suggested delivering a live attenuated (weakened) virus raises your innate immune response across the board, helping you fight off other infections. In this case it would be SARS-COV-2. This enhancement of innate immune response would help you clear the initial infection or at least dampen viral replication to help fight it off -- preventing outcomes that would lead to hospitalization. You may encounter some mild symptoms, but its lessens the likelihood of the worse outcomes.
It is just speculation, but this may be why children are seeing less severe disease. If they have their vaccinations, they may be somewhat protected through this mechanism. This "protection" wanes over time, thus older populations being more susceptible. That is why everyone would get a "booster" of this OPV vaccine, to give you this short protection while SARS-COV-2 is currently making the rounds.
Here is an opinion piece from Dr. Chumakov that discusses this possibility. He also recently appeared on TWiV to discuss. Apparently they have been given the green light for a trial, but are currently looking for centers to host and begin enrollment.
Some excerpts are below:
The idea is interesting -- there is old data that suggested delivering a live attenuated (weakened) virus raises your innate immune response across the board, helping you fight off other infections. In this case it would be SARS-COV-2. This enhancement of innate immune response would help you clear the initial infection or at least dampen viral replication to help fight it off -- preventing outcomes that would lead to hospitalization. You may encounter some mild symptoms, but its lessens the likelihood of the worse outcomes.
It is just speculation, but this may be why children are seeing less severe disease. If they have their vaccinations, they may be somewhat protected through this mechanism. This "protection" wanes over time, thus older populations being more susceptible. That is why everyone would get a "booster" of this OPV vaccine, to give you this short protection while SARS-COV-2 is currently making the rounds.
Here is an opinion piece from Dr. Chumakov that discusses this possibility. He also recently appeared on TWiV to discuss. Apparently they have been given the green light for a trial, but are currently looking for centers to host and begin enrollment.
Some excerpts are below:
Quote:
In addition to protecting against polio by inducing antibodies that kill the virus, OPV activates other protective mechanisms, including an innate immune system, thus making people resistant to infections caused by other viruses and bacteria. For example, in large scale multicenter clinical trials conducted in the 1970s during outbreaks of seasonal influenza, OPV protected more people from influenza than most flu vaccines do. Furthermore, observational studies in many countries suggested that the hospitalization rate and the overall mortality among children immunized with OPV were consistently lower compared with unimmunized children, even in the absence of poliovirus in communities.
Related studies revealed that similar nonspecific protection can be induced by immunizing people with measles vaccine, tuberculosis vaccine (BCG) and some other live attenuated vaccines. These observations suggest that the nonspecific protective effects are a result of boosting innate immunity that is our body's front-line defense against infectious agents. This protection would last for a period of several weeks or months preventing or reducing the severity of disease in immunized individuals and slowing down the spread of COVID-19.
Lower incidence of COVID-19 in countries using BCG could suggest that the nonspecific protective effects could last much longer. Involvement of innate immunity could be particularly important because there is an indication that it is suppressed by SARS-CoV-2, while immunization with live vaccines is expected to stimulate it.
OPV is a proven safe and inexpensive vaccine routinely used orally in young infants and even newborn babies around the world. Focused analysis and experimentation will be required to ascertain how best to deploy a vaccine conferring high immunity but for a limited duration.