What Does It Take to Get Vaccines to the End of the Line?

Author: Kristine Liao

Smriti Jain

For many people, the process of getting vaccinated begins and ends at some sort of health facility, where a health care worker sanitizes their arm before injecting a vaccine and sending them on their way.

But in reality, that’s just the end of the line for that vaccine. What it took to get that dose from point A to point B is a whole lot more complicated than simply ordering vaccines, having them delivered, and then having them administered — especially if they are being administered in a rural, hard-to-reach community.

A conglomerate of stakeholders are involved in the process of getting vaccine doses from a manufacturing center, to the airport, onto the ground of the receiving country, and finally to the clinics or mobile sites of local communities. It is a process that requires meticulous documentation and monitoring, rigorous logistical planning, and the mobilization of trusted community members who serve as vaccine ambassadors.

From the Manufacturer to the Airport

The vaccine procurement process begins when countries put in their orders for vaccine doses. If a country is facing an epidemic, the government can request vaccine doses through the World Health Organization’s (WHO) emergency stockpiles. This resource is available for cholera, ebola, meningitis, and yellow fever. Once the order is approved, UNICEF procures the vaccines and organizes their delivery, ideally within a week.

Since there was no preexisting stockpile of COVID-19 vaccines when the pandemic began, wealthier nations ordered doses directly from the manufacturer. Countries that did not have the purchasing power to do so had to rely on vaccine supplies from COVAX, the World Bank, or direct donations from other countries.

The vaccine procurement process begins when countries put in their orders for vaccine doses. Once the order and transportation details are set, the manufacturers process the orders, confirm batch release timelines, and pack the doses for transport.
Image: Smriti Jain

COVAX was founded in April 2020 in response to the pandemic and is a financing tool that aims to ensure equitable and fair access to COVID-19 vaccines. The initiative is co-led by Gavi, the Vaccine Alliance, the Coalition for Epidemic Preparedness Innovations (CEPI), and the WHO.

If countries are obtaining COVID-19 vaccine doses through COVAX or the World Bank, the order details go to UNICEF, which manages vaccine procurement and transportation. Here, officials work through the logistics of obtaining doses from manufacturers and finding flights that can transport the doses to their respective countries.

The process is similar for routine immunizations, including those for polio, measles, and human papilloma virus (HPV), which are made more accessible to low- and middle-income countries by global partnerships like Gavi, and are organized and delivered by UNICEF.

Once the order and transportation details are set, it’s time for the vaccine doses to get on the road. The manufacturers process the orders, confirm batch release timelines, and pack the doses for transport.

For many vaccines, including the ones developed for COVID-19, the distribution of doses requires a “cold chain” to keep the supplies in their recommended temperature range. Cold chain infrastructure enables vaccines to stay potent from the time they are manufactured until the moment of vaccination. Pfizer, for instance, has developed temperature-controlled thermal shippers that use dry ice to keep its vaccines cold. These shippers can maintain the recommended temperature conditions for up to 10 days unopened, allowing the doses to make the journey from a manufacturing center in one country to the airport in another.

From the Airport to the Health Facility

Once the vaccines land in the receiving country, the next step is distributing them to the regional level. First, they are loaded off the airplane and into cold rooms. Here, officials typically do a count of the vaccines to make sure they match the ordered amount and start to figure out what quantities will go to which districts.

Developing Sierra Leone’s vaccine supply chain strategy is one of Joyce Mariana Kallon’s main responsibilities. As the supply chain and logistics team lead for the country’s Expanded Program on Immunization, Kallon designs matrices that determine the movement of vaccines to the country’s 16 districts.

After they land in a receiving country, vaccines need to be distributed at a regional level. They are loaded off the airplane and into cold rooms, where officials do a count of the vaccines and determine the quantities for each district.
Image: Smriti Jain

There are several factors health officials consider when determining the number of doses a certain district receives, including how many medical teams are in the area, how many people they aim to vaccinate per day, and how many days they plan to run the vaccination campaign. These factors can be limited by insufficient medical personnel, a lack of cold storage facilities, and vaccine expiration dates, Kallon explained.

When it comes to COVID-19 vaccines, the doses are then put into cold boxes lined with conditioned ice packs that are designed to keep the temperature stable for 72 hours. These boxes are loaded onto refrigerated trucks, along with syringes, screening forms, and vaccination cards.

“At every point in time of the supply chain, we want to keep the vaccines at the standard 2 to 8 [degrees Celsius],” Kallon told Global Citizen. “We don’t want to compromise the temperature.”

The trucks then make their way to health facilities in the country’s districts. In Sierra Leone, the distribution of vaccines to districts is handled by two trucks — one goes to the North and West of the country, and a second goes to the South and East.

When they arrive at the health facility, the vaccines are immediately put into refrigerators. If a district is not equipped with refrigerators, its designated doses are kept at a nearby district that has the required storage resources. If it’s a remote area, where there are no other facilities nearby, the district keeps the vaccines in the cold boxes they came in and changes the ice packs every 72 hours to maintain the temperature.

From the Health Facility to the Local Community

The process doesn’t stop there. Once the vaccines reach the regional level, it’s time to start distributing them to villages and towns. Countries’ health workers load the determined quantity of vaccines for a certain population into yet another vaccine carrier with conditioned ice packs, and commute by motorbike, by donkey, on foot, or by whatever other means available to administer vaccines in local communities.

Savior Flomo Mendin, Last Mile Health’s county manager in Grand Bassa County, Liberia, oversees the local distribution of vaccines in her country. In Liberia, where 1.2 million people live outside the reach of the health system, long distances and poor road conditions remain significant obstacles for vaccine distribution in remote communities, Mendin said.

From the regional level, vaccines are then distributed to villages and towns. Long distances and poor road conditions remain significant obstacles for vaccine distribution in remote communities.
Image: Smriti Jain

“The further communities can take four to five hours [to reach from the closest health facility],” Mendin told Global Citizen. “There are some communities that are very remote and also pass through unique terrains, so it can take all day, up to eight hours.”

In communities without cold storage facilities, health workers set up mobile vaccination units and typically have to administer the doses the day they receive them in order to ensure they remain potent. This requires significant planning in advance, particularly making sure a sizable portion of the community is ready and willing to receive their immunizations — otherwise, doses will go to waste.

At this stage, vaccine education and trust building are key components to success, especially in communities where people are hesitant about vaccines.

In Sierra Leone, Kallon said they engage community stakeholders like chiefs, chairmen, chairwomen, and religious representatives to urge people to get vaccinated.

“You feel very safe when your own people talk to you, compared to someone who is coming from a very far distance to tell you to do something,” Kallon said. “That’s why our social mobilization effort doesn’t just have the national representatives — we also have people from the community, based on the ground, who are part of the team.”

In Liberia, too, community health workers are a big part of the local vaccination effort.

Mendin’s work supports the training of community health workers, providing them guidance on how to handle and store vaccines, as well as information on how to dispel misconceptions about vaccines and mobilize people to get immunized. These liaisons between the community and health systems have been critical to forming the optics around vaccination and increasing uptake.

Community outreach and mobilization efforts are vital components of global immunization programs.
Image: Smriti Jain

“We saw a lot of receptiveness when community health workers started to step up and take their [COVID-19] vaccines,” Mendin said. “Most of the community already trusts and respects them and their decisions, so when they get vaccinated, it encourages other members of the community to see value in the vaccine.”

Community outreach has been key not just to the COVID-19 vaccination campaign, but to many immunization efforts that have been at work prior to this pandemic.

Health workers who connect the local community to the health system have played an indispensable role in helping the Global Polio Eradication Initiative (GPEI) vaccinate more than 2.5 billion kids. The success of Gavi’s routine immunization efforts, which have vaccinated more than 888 million children in 77 countries, would not have been possible without the support of civil society organizations that deliver up to 65% of immunization services in some countries.

This is what it takes for vaccines to get to the end of the line. It may start with a manufacturer and international entities like COVAX, Gavi, the World Bank, and UNICEF, but it relies on so much more than that. It requires airplanes, refrigerated trucks, cold boxes, and ice packs — and it all comes down to the planning, strategies, and critical outreach of health workers around the world.


The End of the Line series looks at the amazing ways in which the world is reaching the “last mile” with vaccines. It covers what it’s like to deliver vaccines in war-torn settings, as well as hard-to-reach areas, while highlighting the role of community health workers and the logistics involved in vaccine delivery.

Disclosure: This series was made possible with funding from the Bill and Melinda Gates Foundation. Each piece was produced with full editorial independence.