Vaccination is one of the most effective tools for preventing infectious diseases in both humans and animals. Safe and effective vaccines reduce mortality, improve productivity and protect communities from zoonotic diseases that can cross species barriers. However, the success of vaccination programs depends not only on the quality of vaccines produced but also on how they are stored, transported and handled. When vaccines are exposed to temperatures outside their recommended range, their potency can decline, leading to a failure to generate adequate immune protection. Such failures can erode public trust when vaccinated individuals, both human or animal, still fall ill with the targeted disease.
Maintaining vaccines within the correct temperature range from the point of manufacture to administration is therefore critical. The temperature-controlled system that preserves vaccine potency along the travel route is known as the cold chain. A robust cold chain ensures that vaccines remain active and efficacious until their expiry date, forming the backbone of successful immunisation and vaccination programs.
Public health systems worldwide devote substantial resources to building and maintaining cold chain infrastructure. An effective cold chain requires three key elements. First, personnel: trained staff to manage vaccine storage and distribution at every point in the system, ensuring that handling protocols are consistently applied. Second, equipment: reliable refrigeration and transport equipment capable of maintaining required temperatures, together with temperature-monitoring devices that allow real-time oversight. Third, procedures: standardised protocols that guide proper equipment use, temperature monitoring, and the safe transport and storage of vaccines.
When any of these components fail, whether due to lack of training, power outages or equipment breakdowns, the integrity of vaccines can be compromised. For this reason, continuous investment in cold chain systems is not optional but essential for sustaining vaccine confidence and effectiveness.
While public health vaccination programs often receive strong institutional and financial support, animal health services in many low- and middle-income countries remain under-resourced. The consequences are significant: inadequate cold chain capacity can lead to unreliable vaccine supplies, loss of potency and high mortality from diseases that are otherwise preventable.
These weaknesses in animal health systems have several important wider implications. Livestock owners who experience disease outbreaks following vaccination may lose confidence both in vaccines and in veterinary health care services. High animal mortality can make it difficult to detect outbreaks early, diminishing the sensitivity of surveillance systems. Poor disease surveillance allows zoonotic pathogens — that is, those that can infect both animals and humans — to circulate unnoticed in animal populations, potentially spilling over into human communities. Finally, these outbreaks may have serious negative impacts on household livelihoods and national economics.
As a consequence, inadequate investment in animal health cold chains not only affects livestock productivity but also undermines public health security and food systems.
Encouraging progress has been made in Bangladesh, where a community-based One Health initiative funded by the USAID Feed the Future Bangladesh Livestock and Nutrition Activity and UK Research and Innovation-funded One Health Poultry Hub has highlighted the benefits of shared responsibility across sectors. A farmer survey conducted under the Bangladesh Livestock and Nutrition Activity revealed very low levels of vaccination coverage. This finding was presented at a national meeting that brought together public health, animal health and environmental health officials, along with local government representatives, reflecting the essence of the One Health approach, which seeks to balance and optimise the health of people, animals and ecosystems through cross-sectoral collaboration.
Public health officials were surprised to learn about the low coverage of livestock vaccination for two key reasons. Firstly, in rural districts facing high child undernutrition, improving access to nutrient-rich animal-source foods is seen as vital. Second, frequent high mortality in animals reduces surveillance sensitivity and timely disease outbreak reporting. Rather than attributing blame to veterinary services, they expressed readiness to support joint action. Proposed areas of collaboration included cold chain training, shared maintenance responsibilities and coordinated monitoring of livestock vaccination coverage. They further recommended that animal vaccination data, particularly for zoonotic and high-priority diseases, be routinely shared with District Public Health Nutrition Committees. This integration would help raise awareness of challenges in veterinary health systems and strengthen links between animal health and human nutrition initiatives.
Importantly, discussions also explored the potential for shared cold chain infrastructure. Public health facilities in Bangladesh now possess well maintained refrigeration units, backup power generators and trained personnel. Public health officers felt that, with proper coordination, these existing structures could benefit veterinary vaccination programs — and were keen to take this idea forward. (While the World Health Organization prohibits human and animal vaccines from being stored in the same refrigerator, this barrier can be overcome by installing separate storage units powered by a unified electricity source and shared backup systems.)
This example from Bangladesh illustrates the value of the One Health approach in addressing common logistical challenges. In many contexts, animal health and public health services operate in parallel, each maintaining their own infrastructure, staff and supply systems. However, greater efficiency and resilience can be achieved through integrated planning and resource sharing. Beyond Bangladesh, this idea is also being considered in the four countries participating in the West African One Health project — Sierra Leone, Guinea, Liberia and Nigeria — which aims to strengthen the mitigation and prevention of outbreaks and address sectoral inequities through increased multisectoral collaboration.
In fact, the Guinean National Health Security Agency is currently coordinating with the National Directorate of Veterinary Services regarding the storage and distribution of dog rabies vaccine. In Guinea, rabies vaccines are distributed through a tiered system to maintain cold chain integrity. Vaccines are first stored at four regional veterinary laboratories, then transferred to refrigerators within the Prefectural Directorates of Livestock, and subsequently to human health centres at the sub-prefectural level. Transport is conducted using coolers with regularly-replaced ice packs. Most health centres are equipped with solar-powered refrigerators. Coordination between the Expanded Vaccination and Primary Health Care Program and the National Directorate of Veterinary Services ensures effective management and safety of animal vaccinations.
Access to potent vaccines, safe food and effective disease control underpins both human and animal health. Yet sustaining these systems requires collaboration across sectors that have traditionally worked in isolation. The One Health approach offers a pragmatic and equitable framework for doing so. By sharing cold chain resources — equipment, expertise and maintenance systems — countries can strengthen both public and veterinary health services while maximising the impact of limited resources. In short, investing together means saving together: protecting livestock, safeguarding people and securing the health of the ecosystems we all depend on.
This blog on integrated cold chain management is really interesting and very relevant for ensuring good-quality vaccines. In many low- and middle-income countries, especially in rural areas, maintaining the cold chain remains a major challenge that can undermine national vaccination efforts.
For example, in Burkina Faso, technical livestock support units at village level do not have adequate cold storage equipment. As a result, vaccinators must travel long distances to obtain vaccines at the commune level and to store any remaining doses. In some cases, they temporarily store animal vaccines in the local health centres called Centre de santé et de promotion sociale (CSPS). However, during inspections this becomes problematic, since human and animal vaccines should not be stored together. This is why I find the suggestion of shared cold chain responsibilities particularly relevant. With proper coordination and separate storage units, this approach could help address current logistical constraints and ensure that potent, high-quality vaccines are delivered to animals.
However, I do have one question: would such shared systems be intended only for zoonotic diseases? Human health services may see limited benefit in supporting shared cold chain management for vaccines targeting non-zoonotic animal diseases. I would be very interested in hearing your thoughts on this point.
Thanks very much Eunice for highlighting the animal vaccine cold chain challenges in Burkina Faso. To answer your question, I would hope that a One Health cold chain would support all relevant animal vaccines, including vaccines that prevent non-zoonotic animal diseases. Endemic diseases, such as PPR in small ruminants and Newcastle disease in chickens, indirectly affect human health through their impact on food security, quality nutrition and livelihoods.
A practical solution for improving cold chain management of vaccination in Bangladesh is to adopt a shared, One Health-based system where public health facilities support veterinary vaccination programs through jointly managed cold chain infrastructure. This includes installing separate storage units for human and animal vaccines powered by shared electrical and backup systems, offering joint cold chain training, and coordinating maintenance and monitoring across sectors. Integrating animal vaccination data with district public health reporting and using renewable energy like solar-powered refrigerators can further strengthen resilience. By pooling resources and adopting unified planning, Bangladesh can enhance vaccine safety, reduce costs, and improve disease control in both humans and animals.
Thanks very much Esha for your encouraging comments. It is great to see Bangladesh, once again, leading on One Health implementation.
Thank you for sharing this concept. Strengthening collaboration between human and animal health systems is essential for improving vaccine cold chain management in LMICs and regions facing instability an approach fully aligned with the One Health vision. Shared logistics can make a real difference. Many health teams cannot reach remote or insecure areas, but coordinated transport, storage and information-sharing allow both human and animal health services to extend their reach to vulnerable communities.
This gap is especially clear in unstable regions where humanitarian providers often focus only on human health. Livestock keepers may need vaccines for their animals but cannot access them. A collaborative One Health oriented system would enable efficient delivery of both human and animal vaccines to those who rely on them. The WHO recommendations could be a barrier to this integrated system. Revisiting these policies could open the door to more resilient, inclusive, and cost-effective vaccine delivery for all.
Thank you, Arouna, for your insightful comments. Indeed, the importance of ensuring vaccine availability for people and animals in insecure areas is of vital importance to effective disease prevention and control.
I found this blog incredibly useful, especially the detailed examples of how coordinated cold chain systems can support both public and veterinary health services. It really shows how One Health collaborations can create real impact on the ground. I’m curious — what do you think are the biggest challenges countries face in scaling up these integrated approaches?
Thanks Munira for your positive comments and very important question. To answer your question, I guess we need to engage with national health services and relevant global agencies to better understand their perspectives.
Speaking from the human public health part of the One Health team, I heartily endorse the ideas in this post. Pragmatic sharing of resources benefits us all.
In fact, my first introduction to One Health thinking was a related idea: years ago, I was working at provincial level in central Mozambique. We human health workers had a very successful programme of childhood vaccination, but human rabies vaccine was costly and beyond our reach. We were seeing a number of preventable human rabies cases every year, often where a dog foraging in the forest came home infected and bit its owner. On the other hand, our veterinary colleagues had an African-made canine vaccine but no community connections. The answer was for us to invite our community contacts to a vaccination day, but asking them to bring their dogs instead of their children. The idea was well received, many dogs were vaccinated, and the following year there were no human cases in the province.
Thanks so much Jim for endorsing the concept of a One Health approach to vaccine cold chains and for sharing your excellent example of One Health in action.
Great to see the vaccination delivery chain highlighted. In the One Health world we have talked about the need to share infrastructure across health systems to get the best for people’s health and the health of the animals they depend on. The WHO recommendations seem like a barrier to achieving this, my question is why has this not been addressed?
Thanks Jonathan for your comments and insightful query. Advancing the concept of One Health cold chains would likely benefit from some One Health economic modelling that, if found to yield positive outcomes, could be presented for discussion by the Quadripartite. What are your thoughts regarding next steps?
It would be great for Bangladesh if the vaccines can be delivered maintaining the cold chain using the public health infrastructures. People from remote areas cannot think of doing animal vaccinations as they need to go to specific veterinary hospitals far from their houses, which also incurs a varying amount of costs to the owners. Great initiative. Hope it can be achieved through One Health.
Thanks very much Jinnat for your positive comments. A One Health approach to vaccine cold chains can be an important opportunity for it to demonstrate positive impacts at the community levels and on the national budget.