Fifty years of immunisation in Africa: the evolution of vaccine supply chains

¹World Health Organization Regional Office for Africa, Brazzaville, Congo, ²Department of Community Health Studies, Faculty of Health Sciences, Durban University of Technology, Durban, South Africa, ³School of Health Systems and Public Health, Faculty of Health Sciences, University of Pretoria, Pretoria, South Africa, ⁴Cochrane South Africa, South African Medical Research Council, Cape Town, South Africa

^&Corresponding author
Chinwe Juliana Iwu-Jaja, World Health Organization Regional Office for Africa, Brazzaville, Congo

Essay    

Immunisation remains one of the most effective and cost-efficient public health interventions, yet its success depends heavily on countries' ability to store, transport, and deliver vaccines under strict conditions. In the World Health Organization (WHO) African Region, with its vast geography, diverse climates, and fragile health systems, vaccine supply chain evolution has been central to immunisation progress. From the establishment of the Expanded Programme on Immunisation (EPI) in the 1970s to recent advances in energy-efficient cold chain equipment, digital visibility, and continental vaccine self-reliance, these supply chains have undergone significant transformations. The journey from basic vaccine distribution networks to sophisticated logistics systems reflects broader development trends across Africa whilst highlighting unique contextual challenges. Understanding this evolution provides critical insights for policymakers, public health practitioners, and development partners working to strengthen immunisation systems. This paper provides a historical and thematic analysis of vaccine supply chain evolution in Africa, highlighting milestones, persistent challenges, and forward-looking priorities necessary for achieving sustainable vaccine security.

Historical evolution and progress

Foundations: early immunisation infrastructure development

Africa's vaccine supply chain has undergone profound evolution over recent decades. In the mid-20th century, vaccine access was extremely limited outside ad-hoc campaigns, and infrastructure for safe storage and delivery was virtually non-existent. A major turning point came in 1974 when WHO launched the EPI, catalysing African countries to establish national immunisation programmes and build foundational supply chains from central vaccine stores to village health posts [1,2]. Early pioneers in African immunisation logistics helped design and test the first comprehensive cold chain systems suitable for low-income settings [1]. Over ensuing decades, Africa's vaccine supply chain expanded from these rudimentary beginnings into a coordinated system encompassing international procurement, extensive distribution networks, cold chain technology, and trained personnel. Each link-manufacturing, procurement, logistics, cold storage, data tracking, and workforce, has seen significant developments that have collectively transformed the continent's capacity to deliver lifesaving vaccines to its population.

Local vaccine manufacturing in Africa

One longstanding challenge has been Africa's dependence on imported vaccines. Historically, only a handful of countries produced vaccines locally. Institutions like Senegal's Institut Pasteur de Dakar (producing yellow fever vaccine for decades) and Egypt's state vaccine institute exemplified early manufacturing capacity [1]. However, for most of the late 20^th century, African countries relied almost entirely on imports. Currently, fewer than 10 African manufacturers in only five countries (Egypt, Morocco, Senegal, South Africa, and Tunisia) engage in vaccine production, mostly limited to packaging or filling and finishing rather than end-to-end manufacture [1], while Africa imports around 99% of its vaccines [3]. This over-reliance was starkly highlighted during COVID-19, when African countries struggled to obtain timely supplies whilst higher-producing regions secured bulk doses [4], a disparity underscoring the continent's vulnerability due to limited local production.

In response, there is now a strong push for vaccine self-sufficiency, with ambitious goals to produce 60% of vaccines needed in Africa locally by 2040 [5-8]. This vision, described by Africa CDC as akin to Africa's "second independence" in health security is backed by strategic initiatives. The Partnership for African Vaccine Manufacturing (PAVM) coordinates investments and technology transfer for new manufacturing facilities [3]. Some countries are planning or building new vaccine plants, including mRNA production hubs in Rwanda and South Africa, and expansion of Institut Pasteur in Senegal [4-6]. Achieving these plans requires developing robust supply chains for specialised raw materials and equipment, plus stronger regulatory systems to assure quality.

Procurement and funding mechanisms

African countries' vaccine needs were largely met via international procurement and donor support. As national immunisation programmes took off under EPI, UNICEF became the primary procurement agent, supplying vaccines (often donated or subsidised) to most African countries [7]. In the late 1980s, the global Universal Childhood Immunisation effort poured substantial external resources into vaccines and cold chain equipment for Africa [8], establishing a precedent of centralised procurement where UNICEF aggregated demand and purchased vaccines in bulk for dozens of low-income nations. This model continues today. Most African countries procure vaccines through UNICEF Supply Division with support from Gavi, the Vaccine Alliance, founded in 2000 to finance immunisation in the world's poorest countries [9,10]. Thanks to Gavi funding, African immunisation programmes introduced many new vaccines (hepatitis B, Haemophilus influenzae type b, pneumococcal conjugate, rotavirus, and others) throughout the 2000s and 2010s [11]. However, this meant greatly increased volume and variety of vaccines to handle, stressing supply chains originally designed for fewer antigens. Recent efforts have strengthened Africa's ownership and resilience in vaccine supply. Regional bodies and pooled procurement mechanisms are emerging. During the COVID-19 pandemic, the African Vaccine Acquisition Task Team (AVATT) was formed to collectively negotiate and purchase vaccines for African Union member states, a novel approach complementing the COVID-19 Vaccine Global Access (COVAX) facility [12]. Similarly, Africa CDC and UNICEF have agreed to collaborate on an African pooled procurement mechanism for routine immunisation supplies to ensure more timely and equitable access [13].

Logistics and distribution networks: innovation in last-mile delivery

Once vaccines arrive in-country, they must travel through storage facilities and transport networks to reach every community. The structure of these distribution networks has evolved significantly since early EPI days. In the 1980s and 1990s, most countries employed multi-tier systems: vaccines moved from national central stores to regional or provincial stores, then to district stores, and finally to front-line health facilities [2]. This cascading supply chain was necessary due to limited transportation infrastructure and the need to maintain the cold chain at every step. Over time, countries have optimised these designs. Some have reduced tiers (bypassing intermediate stores) to speed deliveries and improve vaccine quality [14,15]. Others shifted from "pull" systems (where clinics order vaccines) to "push" or informed push systems (where higher levels proactively send supplies based on need) to prevent stockouts in remote clinics [15]. A noteworthy trend has been private sector involvement and innovation in last-mile delivery [16]. Some African countries have experimented with outsourcing vaccine distribution to logistics companies to leverage efficiency and fleet networks. In South Africa's Western Cape Province, the government contracted a private partner (Biovac) to manage storage and delivery of all vaccines to clinics. Evaluation of this public-private partnership found that outsourced distribution maintained vaccine quality, met delivery timelines, and was cost-effective. It even helped the province respond effectively to a sudden measles outbreak in 2010 [17].

Perhaps the most striking advances in African vaccine logistics have addressed the "last mile" problem reaching remote, hard-to-access communities. Traditionally, health workers trekked on foot or used canoes, motorcycles, and even camels for final destinations. Today, drone technology bridges these gaps. Rwanda led the way in 2016 using Zipline's unmanned drones to deliver blood products to rural clinics, soon extending this model to vaccines [18]. Ghana followed in 2019 with one of the largest vaccine drone delivery networks in the world, supported by Gavi [18]. This innovation has prevented stockouts by enabling instant resupply when clinic vaccine stocks run low. Drones have dramatically cut delivery times in difficult terrains from hours or days to minutes, ensuring even children in remote villages can be reached quickly. Other countries like Malawi and Nigeria are piloting drone delivery in specific districts [19,20].

Cold chain infrastructure and technology: from basic refrigeration to sophisticated systems

The cold chain, the system maintaining vaccines within safe temperature ranges (typically 2-8°C) from manufacture to use, is the backbone of vaccine supply chains. In Africa's tropical climates, maintaining this cold chain has always been critical. During initial EPI rollout in the 1S970s, many countries had to create cold chains from scratch. Early assessments found that ordinary domestic refrigerators and picnic coolers brought from Europe were ill-suited for African contexts, often breaking down in heat or during transport [1]. This led WHO and partners to design more robust solutions: sturdy cold boxes and vaccine carriers, kerosene- or gas-powered refrigerators for areas without electricity, and later ice-lined refrigerators that could stay cold for days despite power outages. By the end of the 1980s, virtually all African countries had functional cold chains reaching most health centres [1].

One landmark innovation was the introduction of vaccine vial monitors (VVMs). In the late 1970s and 1980s, WHO and PATH collaborated to develop a visual way to track whether vaccine vials had been exposed to excessive heat. This resulted in small heat-sensitive labels that gradually change colour as cumulative heat exposure increases. By the mid-1990s, VVMs were implemented on oral polio vaccine vials and later on virtually all UNICEF-supplied vaccines [2,21]. The impact was enormous: health workers could see at a glance if vaccines were still good, reducing waste and enabling safe use in high-temperature field conditions previously deemed too risky.

VVM technology laid the groundwork for more cold chain flexibility. In 2012, a new meningococcal A vaccine (MenAfriVac) became the first approved for Controlled Temperature Chain (CTC) use, meaning it could be kept at temperatures up to 40°C for limited periods (up to four days) during mass campaigns [22]. Benin's 2012 meningitis campaign demonstrated this approach's success as vaccinators could carry MenAfriVac in the field without ice packs, yet vaccines remained potent in temperatures up to 39°C [23]. Following this breakthrough, efforts have extended CTC use to other vaccines for campaigns in Africa's hottest regions [22].

Beyond novel products like VVMs and CTC, African cold chain capacity has expanded in volume and improved in quality. In the 2000s and 2010s, Gavi and partners made major investments replacing ageing equipment and installing new cold chain storage at all levels. Since 2017, Gavi's Cold Chain Equipment Optimisation Platform (CCEOP) has helped African countries deploy tens of thousands of modern refrigerators and freezers (including over 45,000 solar-powered units) and hundreds of walk-in cold rooms [24]. Latest vaccine refrigerators are more reliable, solar units no longer require battery maintenance (using "solar direct drive" technology), and many are equipped with digital temperature monitors or remote alarms.

Digital tracking systems: from paper records to real-time monitoring

In the pre-digital era, vaccine logistics in Africa were managed with paper forms, ledgers, and manual reporting. Health facilities recorded vaccines received and used in logbooks, and supervisors compiled monthly reports by hand, making it difficult to have timely visibility into stock levels or quickly rebalance inventory between locations. Over the last 10-15 years, there has been a concerted move towards digital information systems. Early steps included Excel-based stock management worksheets and mobile phones (SMS) for reporting stock on hand. As internet connectivity and computer access improved, many countries deployed electronic logistics management information systems (eLMIS) dedicated to vaccines [25]. Benefits of digital systems are already evident. Real-time stock tracking and data dashboards help managers identify which districts are running low on which vaccine or which storage freezers need maintenance. A recent multi-country evaluation (including Guinea, Rwanda, and Tanzania) found that implementing eLMIS was associated with reduced vaccine stock-outs at health facilities [25]. Moreover, digital records improve data accuracy and save health workers time: over 80% of users reported faster workflows with electronic registries [25]. Ethiopia, Nigeria, Zambia, and Kenya are among countries introducing electronic vaccine stock management, often starting at sub-national levels and scaling nationally.

Digital tools extend beyond inventory management. Many African immunisation programmes now use electronic temperature monitoring devices such as remote temperature sensors that send SMS alerts if freezers go out of range, or data loggers that record temperature throughout vaccine shipment journeys. Global Positioning System (GPS) and mapping software optimise delivery routes and map populations for reaching zero-dose (unvaccinated) children. Electronic immunisation registries (EIR) are being implemented in countries like Rwanda to track individual vaccination records and flag defaulters, often linked with eLMIS so supply and demand data connect. Beyond these digital systems, artificial intelligence (AI) is beginning to play a role in vaccine supply chains. AI-powered tools have been piloted to strengthen predictive demand forecasting, optimise distribution routes, and provide real-time decision support for managers [26,27]. In Africa, such innovations are still at an early stage but hold significant potential to complement existing eLMIS and electronic registries by reducing stockouts, improving delivery efficiency, and enabling faster responses to supply disruptions. As connectivity expands, integrating AI into national immunisation programmes could become a critical step in achieving sustainable vaccine security.

Workforce and human capacity development

Building and maintaining effective vaccine supply chains is ultimately a human endeavour. In early immunisation programmes, supply chain duties were often added to health workers' responsibilities with little specialised training. As immunisation systems grew, it became clear that competent, dedicated workforces were needed at all levels to manage increasingly complex logistics. A major shift came in the late 1980s when WHO and UNICEF helped establish TechNet as a global network of immunisation logistics professionals [1]. TechNet provided forums for cold chain officers and EPI logisticians, including many from African ministries of health, to share best practices and standardise approaches. This community played a key role in spreading innovations like preventive refrigerator maintenance and implementing auto-disable syringes.

Despite such efforts, assessments into the 2000s found that many countries' immunisation supply chains had under-qualified and under-supported personnel. Supply chain roles were often not formally recognised as professions; staff managing vaccines were frequently untrained, with limited career growth and little authority within health ministries [28]. To address these gaps, Gavi launched a comprehensive Immunisation Supply Chain Strategy in 2014, emphasising "people and practice" as one of five fundamental building blocks [28]. This strategy advocated for every country to appoint an immunisation supply chain manager and pushed for more systematic capacity building: developing supply chain training curricula, instituting supportive supervision, and creating professional recognition for this cadre [28].

Progress has been steady over the past decade. By the mid-2010s, nearly two-thirds of African countries had created dedicated immunisation logistics or supply chain manager positions at national level, signalling growing recognition of the need for specialised leadership [29]. Training opportunities have expanded, for example, the Agence de Médecine Préventive (AMP) established the LOGIVAC training centre in Benin to provide professional development for francophone African immunisation logisticians [30]. WHO and UNICEF have institutionalised periodic effective vaccine management (EVM) assessments, which benchmark performance and foster regional peer learning [31].

Africa's vaccine supply chain has evolved remarkably from the fragile systems of the 1970s to today's increasingly sophisticated networks. Each stage of this journey has brought progress, from building basic cold chains and procurement systems, to scaling volumes and integrating new technologies, and now to digitalisation, regional coordination, and renewed focus on local production. These advances show Africa's resilience and capacity to adapt, often under difficult conditions. Yet, the task is far from complete. Gaps in infrastructure, financing, human capacity, and regulatory systems still threaten the reliability of vaccine delivery. The COVID-19 pandemic laid bare these weaknesses while also creating momentum for change, particularly around the push for continental manufacturing. The African Union's target to produce 60% of vaccines locally by 2040 is both ambitious and necessary, linking public health security with broader development goals. Moving forward, success will depend on sustained political will, regional integration, skilled personnel, and strong partnerships. If achieved, Africa's vaccine supply chain will not only secure reliable access to vaccines but also symbolise a shift towards self-determination in health, ensuring every child is protected against preventable diseases.

Authors' contributions    

The study was conceptualised by Chinwe Juliana Iwu-Jaja. Chinwe Juliana Iwu-Jaja, Akhona Victress Mazingisa, Chidozie Declan Iwu and Charles Shey Wiysonge contributed to different sections of the paper. All authors read and approved the final version of the paper.

References