COVID-19 | Now that we have a vaccine, how can we distribute it to people?

The first Europeans are expected to be able to get a COVID-19 vaccine as early as the end of the year – next week for the British – after several pharmaceutical companies announced conclusive clinical trials and the UK has approved Pfizer’s vaccine. / BioNTech.

So it seems that a vaccine has been found in record time and now the focus is on the challenge of distributing it to the world’s population of 7.5 billion people.

We spoke with two experts to find out what are the main obstacles that health authorities will have to overcome in order for the vaccine to be distributed in all corners of the world.

Manufacturing capacity

All three candidate vaccines require two injections, although interestingly, AstraZeneca / Oxford University has proven to be more effective when the first injection is half a dose.

AstraZeneca has announced plans to produce 3 billion doses over the next year while BioNTech / Pfizer plans to make 1.3 billion.

These goals “appear to be feasible,” said Dr Zoltan Kis, from the department of chemical engineering at Imperial College London. “However, the global demand by assuming 2 doses per person is far from being satisfied by the end of 2021.”

Prashant Yadav, professor of strategy at the INSEAD business school, told Euronews that “it could take up to two and a half years to manufacture the more than 10 billion doses needed for global coverage.”

Storage temperature

“Routine vaccines are stored and distributed between 2-8 ° C. There is sufficient infrastructure for cold storage and distribution at that temperature range in high-income countries, and thanks to the efforts of GAVI (the Alliance for Vaccination), the Gates Foundation and UNICEF, have also created in Africa, South Asia and other less developed regions of the world sufficient capacity to store and distribute vaccines between 2-8 ° C, “said Yadav.

The problem is that of the three vaccine candidates so far, only one falls in that temperature range: AstraZeneca’s.

The Pfizer / BioNTech and Moderna vaccines have cooling requirements of -70 ° C and -20 ° C respectively.

“Pfizer-BioNTech vaccines require a [infraestructura] frozen chain that does not even exist in the EU and the US, with the exception of some academic medical centers and some specialized distribution centers, “he added.

Pfizer has developed a special freezer box that can keep the vaccine safe for handling for up to 10 days, but still, its distribution to “low- and middle-income countries or rural areas of other countries is difficult due to the lack of of proper freezing temperatures, “said Dr. Kis.

As for the Moderna vaccine, according to Yadav, although “it can resist between 2 and 8 ° C for a few weeks”, the manufacturing capacity “is not that great”.

“Therefore, their supplies would not be available outside the US, Canada and the EU,” he added.

Overall, Dr. Kis concluded, “Europe and North America are considered to have the highest vaccine distribution and storage capacity at low temperatures, such as -70 ° C, relative to their population.”

“On the other hand, sub-Saharan Africa is considered to be in the worst position when it comes to the distribution of vaccines at low and ultra-low temperatures,” while “the other continents are somewhere in between,” he added.

Urban versus rural

Due to cooling needs that will also affect transportation, access to the vaccine in rural and remote areas will be more difficult than in large cities.

Additionally, Pfizer’s vaccine packaging is in 1,000-dose containers, according to Yadav.

“Some rural clinics do not have the capacity to absorb as many doses in a short time interval of 2 to 3 days. In rural areas there is a lack of staff who can act as administrator of the vaccine.

“Administration of the vaccine also requires PPE [equipo de protección personal] for the personnel who will administer the vaccine and the supply chain to deliver the PPE in rural areas is a challenge, “he also noted.

“Very difficult” immunization campaigns

“Administering vaccines to patients is another highly complex process,” said Dr. Kis.

This is due to the time needed to immunize people – including a 10-15 minute recovery period after the vaccine is administered – and to record each procedure correctly.

The requirement for social distancing and the “limited number of doctors / vaccinators available per capita” – which is even lower in low- and middle-income countries – compound the problem.

“In addition, the administration of the vaccine requires a greater degree of human involvement, so additional problems / issues may arise at this stage, especially considering that it is necessary to administer two doses of vaccines per person, usually with an interval of 3 to 4 weeks, “he added.