A massive logistical operation is underway Monday, to transport millions of doses of the Pfizer-BioNtech vaccine, stored at negative 70 degrees Celsius, across the United States, in preparation for the start of a vaccination campaign against the pandemic.

The enormity of the operation reflects the seriousness of the situation in the US, where the death toll from COVID-19 is expected to exceed 300,000, equivalent to the population of Cincinnati, Ohio.

Sunday, a convoy of trucks loaded with doses of the vaccine departed from the Pfizer factory in Kalamazoo, Michigan, stored in special boxes of 4,725 doses each, bound for the centers of UPS and FedEx, which are tasked with distributing vaccines to different regions.

According to Pfizer, 20 planes will work daily to transport the vaccines in preparation for distribution across the country, especially to the Native Americans from the Navajo tribe, who are severely affected by the pandemic.

- Vaccination begin Monday-

The logistical process aims to deliver the first batches of the vaccine to all hospitals and care centers that have requested it within 24 hours.

"I hope that will happen very quickly. I hope (as of) tomorrow," the head of the US Food and Drug Administration (FDA) Stephen Hahn, told CNN.

Half of the available 6.4 million doses will be delivered immediately, while the other half will be left for the second administration of the vaccine.

The Centers for Disease Control and Prevention (CDC) recommended that those aged 16 years and above be vaccinated, and that priority is given to elderly citizens in care centers (three million people) and health sector employees (21 million people).

The US government has previously ordered a hundred million doses of the vaccine, which has a 95 percent efficacy.

Additionally, the United Kingdom has already started using it in a vaccination campaign to tackle the pandemic.

Although the New Jersey vaccination campaign will begin Tuesday, Governor Phil Murphy has warned of "hell" in the state in the coming weeks, urging residents to avoid family gatherings as the holidays approach.

Experts say achieving herd immunity, which is synonymous with returning to a regular life, requires between 75 and 80 percent of the population to be vaccinated. The scientific advisor to the process of distributing vaccines Moncef Salawi excludes the occurrence of this matter before "May or June."

This article will be updated as more information is announced.

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