Summary of TWIV 663, "The Joy of Vax": About Accelerated Vaccine Approval

 A summary of Alan Dove's segment of This Week In Virology episode 663, "The Joy of Vax", relating to the status of COVID-19 vaccines, as bullet points. He attended a webinar from the National Adult and Influenza Immunization Summit regarding COVID-19:

• Top level executives from eight of nine companies the furthest ahead in vaccine trials participated (Astra Zeneca declined, for the obvious reason that they had halted their trial): Pfizer, Moderna (CEO participated), Novavax, Inovio, Medicago, Sanofi Pasteur, J&J, and Merck.
  
• "We're all in this together". Cooperation among competitors is significant.
  
• Prevention of disease is the primary goal, not sterilizing immunity.
• The bar is set for a minimum of 80% efficacy. (FDA will accept anything over 50%, but the Bill & Melinda Gates Foundation has set 80% as a minimum.)
  
• Because the goal is protective immunity, it's not clear that sterilizing immunity will occur. Therefore, it's quite likely that even vaccinated individuals could act as asymptomatic carriers. This will have consequences for health care workers and the general population.
• "Herd immunity" therefore doesn't have the meaning people suppose it does, because vaccinated asymptomatic carriers can still spread the virus. We need new language to explain how this works. Infection is different from disease.
  
• Consequently, we will need testing to prevent transmission, even with a vaccine.
• All vaccines are two-dose regimens. (Merck believes theirs could be a single-dose.) All expect full approval, but plan on Emergency Use Approval. If you get a vaccine in 2021, it will likely be on an Emergency basis.
• Many of the vaccines will require adjuvants which will need to be added to the vaccine on-site. This is not a problem in the US and Europe, but will be a big problem in developing countries. The plan is to eventually reach single-dose distribution.
• Scaling is enormous. Sanofi, which regularly provides 100M flu vaccines per year, is building out for a billion doses for COVID-19. "People are building entirely new facilities for this stuff."
• Storage will be a non-problem in the western world, but the extreme cold needed (-70C) for mRNA vaccines (Moderna) will be a problem for the developing world. This is a conservative estimate, and research is ongoing for higher temperatures.
• Cross-testing of vaccines is not occurring, so you will need to get the second shot of whatever vaccine you started with to get the benefit.
• Population diversity is a problem in some cases. (Moderna has slowed their trial because they don't have enough African-Americans in their control group.)
  
• Efficacy is assumed to begin 10 days after the second dose. If someone gets sick after the first dose, it does not count.
• Consequently, it's unlikely there will be good data on any vaccine until mid-November. But Pfizer's CEO thinks there will be enough data to say whether a vaccine works by Halloween.
• Worst-case scenario is a vaccine that actually makes infection worse (as the dengue vaccine).
  
• Protection (from disease) is still important even if a vaccine doesn't provide sterilizing immunity, because you could still prevent hospitalization.