Vaccinating the world against COVID-19: How many shots would it really take?

Dubai: The demand for COVID-19 vaccines far outstrips supply today. When do we all get the shots needed to have immunity? The world faces an enormous challenges right now as the largest, most complicated public health drive in history gets underway. The situation, it’s been hoped, would be transient.

Consider the numbers: Epidemiologists state up to 75% of the world’s current population of 7.8 billion should be inoculated — equivalent to 5.85 billion people. With a double dosage (for most vaccines), that brings the number of doses the world needs today 11.7 billion vaccines.

Here’s the good news, sort of: The combined East+West vaccine production capacity stands at 12.18 billion doses, based on our current estimates. These numbers are based on claimed production run rates, multiplied by remaining months to get the total 2021 ballpark vaccine production figure.

The coronavirus has already claimed 2.4 million deaths, having infected 109 million people — about 1.4% of the world’s 7.8 billion inhabitants. In addition to deaths and sickness, virus-driven lockdowns have sent the economy in tatters and experts say a vaccine would greatly help resume.

The real test is whether this manufacturing capacity translates to shots that are shipped for the great multitude on earth waiting for a COVID-19 shot. Here’s the lowdown on the challenge of vaccinating the world against the on-going pendemic:

There are many. The minimum percentage of vaccinations to reach « herd immunity” must be hit. Estimates vary greatly, from 60% to the 90% — the latter figure is the level mentioned by Dr. Anthony Fauci, America’s top infectious disease exper (similar to the level for measles). In which case, the numbers need to be adjusted.

First: production and distribution. Sheer production numbers are daunting, at least in the short term. There’s a growing consensus that the current global vaccine production capacity is nowhere close to the demand. But reports have it that the production run rates are getting ramped up everywhere — the US, Europe, Russia, China, India and Brazil — for at least 8 vaccines (approved in different jurisdictions).

Second, the people who will be vaccinated: In some countries, children younger than 18 comprise up to 30% of their population, yet they’re currently excluded from vaccinations as the shots had not been included in trials. Fresh trials of the approved vaccines on children have started, with results due later this year.

Third, vaccine hesitancy: In certain countries, up to 40% say they have no plans of getting vaccinated against COVID-19. It means even if the shots are made available through bulk government purchases, may may opt out, potential exposing them and those around them.

Not days, but seven (7) years, according to a Bloomberg calculator, citing current rate of inoculations. But it does not account for the expected surge in production. The combined manufacturing capacities of vaccine makers both in the East and the West actually shows a rather optimistic picture. Besides, countries like the UAE have shown that it’s possible to hit 49.56% doses for every 100 people in a rather short span of time (as of February 12, 2021).

It’s worst-case scenario.

The answer is a bit more complicated than throwing up straightforward numbers. In the intense competition for COVID-19 shots, the world faces quite a high bar in bringing those vials to peoples’ arms within the shortest time possible. Our best guess: 18 to 24 months.

Based on Gulf News calculations, using the Boston Consulting figures as base, the most optimistic scenario is a cumulative vaccine production of 12.8 billion shots this 2021 — versus the 11.6 billion vaccines needed to cover 70% of the world’s population at the double-dose prescribed protocol. We don’t claim this to be the gospel truth, and call out out if we missed it, in order to update this story (readers@gulfnews.com).

But it’s a moving target, like an accordion. If the vaccination level is adjusted to 90% (14.04 billion doses), as Dr Fauci has suggested, it would mean a 2.4 billion shortfall in vaccines this year.

It’s something data scientists must continuously crunch, and policy makers must take heed. The production and inoculations may ramped up, as vaccine makers gain more experience from the already mega production rates.

Now, there good news: the tempo of vaccine manufacturing has gone up raised, and so is distribution. As of Saturday, February 13, 2021, more than 171 million doses had been administered across the globe — a 198,648% change from December 13, 2020, according to Our World in Data, which tracks vaccinations. As governments drive up demand and vaccine makers boost capacity — there are signs the run rate will get bumped up.

Do they really work? Here’s a brief history of vaccines

First, not everyone may be vaccinated — or need to be. Our best-case scenario is two years, based on available production figures (as of February 13, 2021) and estimated production capacity by end-2021. This could change, depending on a number of factors, primarily production and distribution.

A single dose from J&J’s vaccine-making arm Janssen, could be a game changer. Another potential game changer: the intra-nasal Covid shot announced by Israel. Another source of optimism, the quicker development time of mRNA vaccine shots for new strains of Pfizer and Moderna.

Also in place is mix of individual, country-level deals, non-profit intervention, and other arrangements to roll out the biggest vaccination campaign, at least for the most vulnerable populations and frontliners in the developing world. Let’s not forget, the first doses are out, and had been used in 171.26 million shots.

Based on existing reports/announcements made by the different vaccine makers, the combined capacities of both the Eastern and Western borks is 12.58 billion, by the end of 2021.

It takes time for vaccines to develop, typically 48 days (for inactivated shots) from cell culture to the vial-in-a-box package. This is a natural limitation due to the conventional vaccine development method. Most inactivated vaccines against viral diseases are made from viruses grown in chicken eggs or mammalian cells. The process of collecting the viruses, adapting them to grow in the lab, and shipping them around the world can take months and is complex.

Production time for mRNA vaccines is relatively much faster. It typically takes one week to generate an “experimental batch”, according to BioNTech. The RNA (which encodes an antigen of the infectious agent) is made from a DNA template in the lab. The DNA can be synthesised from an electronic sequence that can be sent across the world in an instant by computer.

The new mRNA-based vaccines are theoretically faster to produce than conventional ones. It’s unclear at this point how long it takes to generate a batch of, say, 100 million mRNA vaccines. For newly-emerging viruses like SARS-CoV-2, for which a new vaccine is needed as quickly as possible, these may pose a challenge in terms of speed of development.

While production may be faster, mRNA vaccines have one downside: they need super-cooling to keep their efficacy. For example, Moderna’s shot needs -20°C freezing, and Pfizer’s needs -70°C freezing. By comparison, the average Arctic winter temperature is -34°C. 

The biggest advantage of conventional vaccines is, once they’re made, they only need regular refrigeration.

Not yet. Bringing those shots to all corners of the world, including remote areas, is a key hurdle. It would mean the primacy of vaccines that can be stored in regular fridges — or that don’t require cold storage at all. This would mean a more intense demand for the initially limited number of vials for the regular-fridge COVID-19 vaccines.