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Logistics 101: How each COVID-19 vaccine navigates the cold chain

01.23.2021 | By Chris Pickett | 12 min. read

Not sure how COVID-19 vaccine distribution works? We’re here to fix that.

Table of contents

–   How do the two vaccines differ and how do these differences affect transportation logistics?
–   How do the vaccines stay cold during shipping?
–   What are cold-chain logistics?
    –   Transportation
    –   Warehousing: A case study on cold-chain processes in McKesson’s distribution centers
    –   Security
–   Who orders the vaccines and decides where they ship to?
–   What does the vaccine distribution process actually look like?
–   Which carriers are moving the vaccine?
–   What happens when the FDA approves more vaccines?

The Herculean efforts we’re seeing from agents across America to quickly and safely distribute the COVID-19 vaccine certainly aren’t the first of their kind. But, due to the disease’s disastrous toll on American society — and the devastating number of lives lost to the virus — this very well may be the most important vaccine rollout in recent history.

Previous pandemics, such as the 2009 H1N1 swine flu outbreak, built the nationwide vaccination distribution infrastructure that Operation Warp Speed (the public-private task force whose mission is to deliver a vaccine to each and every American who wants one) currently relies upon.

Even with such infrastructures, an unprecedented pandemic like this one calls for new, innovative systems and technologies. For instance, scientists created the first COVID-19 vaccines just 11 months after the discovery of the SARS-CoV-2 virus, thanks to previously-unused messenger RNA (mRNA) technology. (The instability of mRNA, however, is the reason the vaccines require such stringent temperature control during transportation and storage.)

Since the U.S. Food and Drug Administration (FDA) issued emergency use authorizations (EUA) for two coronavirus vaccines — from Pfizer-BioNTech and Moderna — last December, agents across the country have sprung into action to begin moving the crucial cargo to vaccination sites far and wide. When the U.S. began administering the first vaccinations on December 14, 2020, health care workers were the first to receive them.

Manufacturing, transporting, storing, and delivering such a temperature-sensitive product require cohesion from many complicated moving parts, a process the freight industry calls “cold-chain logistics”. Much of this maneuvering remains a mystery to the general public, and a lack of transparency of the processes involved raises the question: How can the American population trust the integrity of a supply chain they’re unfamiliar with?

When dispelling myths about the safety of receiving vaccinations at large, it’s helpful to break down what the journey looks like from manufacturing facility to vaccination site and shine light on all the processes involved.

If you’ve ever wondered what COVID-19 vaccine transportation, distribution, and quality assurance logistics look like, you’ve come to the right place. Prepare to have all your questions answered, and more.

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How do the two vaccines differ and how do these differences affect transportation logistics?

On December 11, 2020, the FDA announced the first emergency use authorization of a COVID-19 vaccine for immediate distribution in the U.S.: the Pfizer-BioNTech vaccine. Pfizer, Inc., an American pharmaceutical powerhouse, and partner BioNTech, a German biotechnology company, developed a COVID-19 vaccine with a 95% efficacy rate. According to the Centers for Disease Control and Prevention (CDC), it recommends this vaccine for patients ages 16 and older and requires two doses, 21 days apart. Only seven days after the Pfizer-BioNTech vaccine authorization, the FDA cleared a second COVID-19 vaccine from Cambridge-based Moderna, Inc. for emergency use on December 18, 2020. Moderna’s vaccine, which the CDC recommends for patients ages 18 and older, has a similar efficacy rate (94%) and requires two shots separated by a 28-day period.

Although both vaccines employ mRNA technology, the differences between their individual structures necessitate vastly different storage environments.

You may have heard that the Pfizer-BioNTech vaccine requires storage at colder temperatures than Antarctica. It’s true — at the risk of ruining the vaccine’s potency during travel, Pfizer’s vaccine must remain at a temperature of -70°C (or -94° Fahrenheit). This poses all sorts of logistical challenges during the shipping process, not limited to the transportation of dry ice (which can be toxic when confined in a small space).

The Moderna vaccine, on the other hand, must remain at a (relatively) balmy temperature of -20°C (or -4°F), making transportation and storage a bit more manageable.

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How do the vaccines stay cold during shipping?

To provide some perspective, the 2009 H1N1 vaccine’s required storage and transportation temperature range fell between 2°C to 8°C (35°F to 46°F). The point being: Each COVID-19 vaccine requires an unprecedentedly cold storage environment from factory to clinic. So, how does each manufacturer accomplish this task?

To ensure that the vaccine remains in the appropriate temperature range, Pfizer takes matters into its own hands. According to its website, Pfizer developed “specially designed, temperature-controlled thermal shippers utilizing dry ice to maintain recommended storage temperature conditions of -70°C±10°C for up to 10 days unopened.” This is more than enough time for the vaccine to reach its intended facility. By traveling via ground and air transportation, the company’s vaccines reach their destination within a day or two.

However, after the vaccine reaches the final administration site, another problem arises. Vaccine administration sites (which can range from hospitals or pharmacies to long-term care facilities or mobile clinics) may lack the super-cold refrigeration systems capable of keeping the vaccine at -70°C. (Typical at-home freezers can only go as low as around -18°C.) Luckily, Pfizer’s carry-on suitcase-size thermal shipper acts as its own refrigeration system, so long as healthcare workers replenish the stock of dry ice every five days.

Moderna’s vaccine follows a slightly different path. After the vaccine leaves the manufacturing facility, it travels to a distribution center where trained staff repack the doses into cool boxes. These cool boxes rely on cold gel packs, rather than dry ice, to keep the vaccine in the proper temperature range. Alongside the vaccines themselves, staff place thermal sensors within each cool box in order to monitor the package’s temperature throughout its journey. After the vaccine reaches the administration site, healthcare professionals can thaw the vaccine, which will remain stable for up to 30 days at standard refrigeration temperatures of 2°C to 8°C. With less stringent temperature requirements, Moderna’s vaccine is easier to store at most pharmacies and clinics.

Still, cool packaging technology is useless if the package falls out of the required temperature zone due to shipping delays, loss, or other supply chain mishaps. That’s where the importance of cold-chain logistics comes in. 

What are cold-chain logistics?

“Cold-chain logistics” refers to every step that a temperature-controlled product takes to get from its manufacturing facility to the point of delivery. Commodities like produce, frozen food, pharmaceutical products, and, yes, the COVID-19 vaccine all travel via cold-chain logistics. It requires precise planning, attention, and cohesion to ensure that products travel through one uninterrupted temperature-controlled process during storage, transportation, and distribution.

There are many complex systems to keep track of in order to ensure quality control in the cold chain. Let’s break it down.

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To ensure product integrity during transportation, companies must be able to prove that the product remained at the appropriate shipping temperature at every point of its journey. To accomplish this, shippers can utilize temperature sensors to upload temperature data to a monitoring center. When it comes to a high-need, high-value commodity like the COVID-19 vaccine, it’s imperative that alarms and systems are in place to alert when package temperatures are falling out of range. This way, the parties involved can take proactive measures to avoid product loss.

When shipping any freight, GPS tracking is hugely important to ensure the package stays on its correct path. IoT companies provide solutions ranging from trailer location tracking with electronic logging devices (ELDs) and GPS devices to improving visibility in the cold chain with remote reefer (refrigerated trailer) temperature monitoring and control technology.

Tracking and tracing the COVID-19 vaccine differ from typical freight tracking because, whereas a freight shipper might only track the truck the freight travels on, vaccine manufacturers and other invested parties may need to track each individual package to ensure they’re all headed to the appropriate state-designated facilities. Ultimately, effectively monitoring vaccine location and temperature requires an advanced framework of connected sensors and systems.

It’s no surprise that COVID-19 vaccine integrity is the top priority for all parties involved in its transport. According to Pfizer’s website, the company tracks the location and temperature of each vaccine shipment using GPS-enabled thermal sensors that upload data to control towers, which monitor product integrity 24 hours a day, seven days a week. Pfizer says these devices allow it to “proactively prevent unwanted deviations and act before they happen.”

UPS, a key transporter of the COVID-19 vaccine, utilizes similar tracking and monitoring technology to ensure the company’s 24/7 Healthcare Command Center can monitor vaccine package location and temperature data.

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Warehousing: A case study on cold-chain processes in McKesson’s distribution centers

It’s important that every party in the supply chain trains their staff, from truck driver to warehouse worker, in handling pharmaceutical goods. To see what this looks like in action, we’ll take a look inside a McKesson distribution center for the Moderna COVID-19 vaccine.

Some background: In August 2020, the CDC named McKesson Corporation, America’s largest seasonal flu vaccine distributor (which also handled the H1N1 vaccine distribution in 2009-2010), the “centralized distributor for COVID-19 vaccines that are refrigerated (2-8°C) or frozen (-20°C).” This means McKesson currently only distributes the Moderna vaccine, leaving Pfizer to distribute its own vaccine directly.

When Moderna’s vaccines arrive at a McKesson distribution center, workers first use monitoring systems to verify the manufacturing facility shipped the vaccines at the correct temperature. From there, McKesson staff members move the Moderna vaccines into a freezer for storage. To ensure product safety, all employees must wear protective clothing before entering the walk-in freezer, including rubber boots, coveralls, protective facial gear, and gloves.

When an order comes in from the CDC, trained product handlers start packing vaccine doses into cooler boxes that keep the vaccines at the required temperature during transit. According to McKesson, “a digital temperature monitor will be packed inside each cooler to provide those receiving and administering the vaccine the confidence that the vaccine’s cold chain was maintained during shipment.”

Once staff have packaged, labeled, and sealed the vaccines in cooler boxes, they load the boxes onto pallets, after which the vaccines are ready for shipment. Typically, vaccine shipments go out within 24 hours after the manufacturer receives the order. With all cold-chain protocols in use and monitoring devices inside each package, McKesson is able to guarantee product integrity from the moment the vaccine arrives at the distribution center to the point it loads onto a carrier’s truck for delivery. From that point forward, the administration site receives the vaccine and assumes responsibility for storing the doses properly.

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When it comes to everyday freight-shipping, you’ll never see armed U.S. marshals patrolling warehouse floors or escorting a freight truck on its way to a distribution center. You will, however, find that it’s typical for cold-chain carriers to go the extra mile to ensure cargo security.

This is especially true for carriers that specialize in moving pharmaceutical freight, like those currently tasked with moving the COVID-19 vaccines. Pharmaceutical shipments typically have higher safety protocols, which lead carriers to use two-driver teams to ensure cargo is never unattended and that trucks aren’t at rest for extended periods of time. According to XPO Logistics President of Global Forwarding and Expedite, Katrina Liddell, XPO’s trailers containing pharmaceutical shipments have “tracing devices on every trailer… and alarms on all the doors.”

With all the data monitoring that goes into ensuring vaccines arrive at their destination under the right conditions, cybersecurity presents an issue as well. When it comes to data security, there can be no weak links.

All this information floating in cyberspace — ranging from GPS locations, temperature readings, remote trailer environment control, and more — poses a risk for cyber attacks. This is why it’s crucial for vaccine manufacturers, as well as carriers transporting the vaccines, to ensure the security of their IoT technologies and mitigate cybersecurity risks with adequate testing and monitoring.

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Who orders the vaccines and decides where they ship to?

Although the federal government oversees the centralized ordering, distribution, and tracking of COVID-19 vaccines, state, tribal, territorial, and local jurisdictions place all vaccine orders with the CDC. The CDC, then, sends the orders received off to the vaccine manufacturers, starting the distribution logistics chain.

Depending on vaccine supply, administration sites either receive the Moderna vaccine from the CDC’s centralized distributor (McKesson) or the Pfizer vaccine directly from the manufacturer.

Although the CDC can make recommendations, it’s ultimately up to each state to create its own vaccine distribution, prioritization, and allocation plan. State officials designate the sites to receive vaccinations, and the number of doses per site.

When it comes to deciding who to vaccinate and when, the Advisory Committee on Immunization Practices (ACIP) determines those recommendations. Again, it’s up to each state to decide whether to follow the ACIP’s recommendations in its vaccine distribution plan.

The ACIP recommended on December 1, 2020 that health care personnel and long-term care facility residents receive the COVID-19 vaccination in the first phase of vaccine rollout (Phase 1a). Later recommendations determined that people 75 years of age and older, non-health care frontline essential workers, and first responders should have vaccine prioritization in Phase 1b. In Phase 1c, the ACIP recommends vaccinating persons 65-74 years old, high-risk people 16-64 years old, and other essential workers (such as transportation and logistics workers). Lastly, Phase 2 includes all other people 16 years of age and older.  

What does the vaccine distribution process actually look like?

Want to know what happens after a vaccine leaves its manufacturing facility?

The answer is, it really depends on the manufacturer.

Pfizer utilizes what it calls “a direct ship distribution strategy”, which means that vaccinations largely travel directly from the manufacturing facility to the administration site and skip distribution centers. Pfizer utilizes a just-in-time (JIT) system which, if you’re unfamiliar with inventory control practices, means that supplies ship out as soon as Pfizer receives an order. This eliminates the need for storing excess products in warehouses (cutting down on operational costs), but can expose supply chain gaps in the case of product shortages.

To put it simply, Pfizer’s distribution strategy flows along the following path: The vaccine leaves the manufacturing facility, travels to a FedEx or UPS facility for distribution by either air or ground transport, and arrives at the administration site.

Because McKesson Corp distributes Moderna’s vaccine, it follows a slightly different path. Typically, Moderna transports the vaccine to a McKesson distribution center, McKesson repackages the vaccines into cool containers, the vaccine stages at the distribution center until pickup by FedEx or UPS, and then FedEx or UPS delivers the shipment to an administration facility via ground or air transportation.

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Which carriers are moving the vaccine?

The main transportation companies tasked with moving the COVID-19 vaccine are UPS and FedEx. However, in the early days of the Moderna vaccine rollout, we also saw subcontractors (such as Boyle Transportation and XPO Logistics) assist with transporting the vaccines to airports and other transfer locations.

Of the smaller carrier partners, fleets that specialize in moving pharmaceutical freight are better prepared to move the ultra-sensitive COVID-19 vaccines. This is because these fleets are experienced in the rigorous temperature tracking and temperature-validated services that are so important during this process. Trucks come equipped with sensors to monitor, record, and report that the trailer temperature remains within the appropriate range. Plus, according to the Wall Street Journal, these fleets already “undergo extensive quality audits and certifications based on global standards for the transport of medicine,” giving Americans peace of mind that the vaccine is traveling according to the highest standards.

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What happens when the FDA approves more vaccines?

More COVID-19 vaccines are currently in development. Interestingly, large-scale manufacturing occurs at the same time as clinical trials so manufacturers may be that much better prepared to begin distributing the vaccine upon FDA approval.

With new vaccines gaining traction in other countries, such as those from AstraZeneca/Oxford and Novavax, it may not be long before we have a third, viable option in the United States. In any case, vaccine distributors and manufacturers have shown that they have the flexibility within their cold-chain processes to accommodate a variety of cold or frozen vaccines.

As stated by Operation Warp Speed, “The eventual objective of the vaccination program is to leave the U.S. government and commercial infrastructure better able to respond to pandemics and public health crises in the future.” If there’s anything the coronavirus pandemic has taught us, it’s the ability for public-private partnerships inside and outside of the health care system to work together in order to mobilize and ensure safe vaccine distribution. We’ve built upon existing infrastructures to roll out the most important vaccine distribution in recent memory, and we’re now better prepared for anything that the future could throw at us.

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