COVID-19: One shot of coronavirus vaccine not enough, say health experts

People will likely need two doses of the COVID-19 vaccine and one shot won’t be enough, Kathryn Edwards, scientific director of the Vanderbilt Vaccine Research program said in a report published by School of Medicine. As in the cases of Varicella, bacterial meningitis, Hepatitis A, B, Polio and many other diseases where more than one vaccine shot is required, COVID-19 would need two-dose series, a month or so apart with booster shots that may be required years later, according to the Vanderbilt Vaccine research. "MERS serology data suggest that by about three years, it could fade,” said Dr. Kathryn Edwards, however, she cited tests would tell if SARS-CoV-2 will need the same booster injection patterns. 

Additionally, some other challenges in administering two doses would be logistical, the supply chain issues, like procuring PPE and test kits throughout the pandemic. A blaring challenge would be to get everyone vaccinated, twice, according to US global analytics firm, Gallup's COVID-19 tracking survey, conducted with members of Gallup's probability-based panel. Associate director for immunization education with the Immunization Action Coalition (IAC) at Vanderbilt University, Dr. Kelly Moore, was quoted as saying that while there is no doubt that the COVID-19 vaccination would be the most complicated, largest vaccination program in human history, it would need a level of effort never tried before.

As many as six pharmaceutical companies have received worldwide funding and in the US via Operation Warp Speed (OWS) to get vaccine shots available for every citizen, as per the reports. While companies like AstraZeneca would enter Phase 3 trials, Moderna and Pfizer have begun the largest human clinical trials for a COVID-19 vaccine ever. With over 30,000 volunteers, the two companies have been administering two doses of the experimental vaccine candidate 28 days and 21 days apart, respectively. 

Meanwhile, according to reports, Johnson & Johnson's upcoming Phase 3 trials will have one shot given to the volunteers, however, Novavax which is yet to enter phase 3 will administer two doses. Although Sanofi, in its race to develop a new vaccine as well as manufacture and supply to curb shortage, hasn’t announced the doses it will experiment in its clinical trials. While there’s still a challenge to arrange two does vaccination for the humungous world population, Moore reportedly said that the companies will have to work with people to make the process work. 

Logistic and Human issues

In the US alone, at least 660 million doses for over 330 million Americans will have to eb manufactured as well as supplied, according to local media reports calculations. A professor of supply chain management at Northeastern University, Nada Sanders was quoted saying by US broadcasters that the companies were looking at the necessary double shots. That's twice the amount, and doubling those doses was a huge supply chain issue. One had to double everything in the supply chain, Sanders stressed. The syringes, the vials, the stoppers, the needles, and getting everyone to get vaccinated twice and in time. “I’m worried,” Sanders said at a televised interview, citing the current pandemic situation with shortages of Shingrix, a vaccine for shingles, an PPE, and ventilators. The countries couldn’t get enough supply of the PPE kits and shortage of N95 masks hit, Sanders reminded. 

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Two-shot regimen had challenges

According to a CNN poll conducted in the month of August for the US, at least 40 percent of the population in the country refused to get the vaccine. While there were hurdles of accommodation to administer two doses such as arrangements of mobile clinics, people themselves were difficult to convince to come twice. Director of the Center for Infectious Diseases Research at Walter Reed Army Institute of Research,  Dr. Nelson Michael, was quoted as saying in a local media report that to incentivize people to come back  and get another shot and for them to adhere to a two-shot regimen, looked like a challenging task. And these challenges are real, he added.

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