Highly Extensible Resource for Modeling Event-Driven Supply Chains

Using a Systems Approach & Systems Modeling for Vaccine Supply Chains


What is a supply chain?
A supply chain is the complex system of equipment, vehicles, personnel, policies and processes needed to deliver a product from its point of origin to the consumer or population.

Why are vaccine supply chains important?
As described in "The importance of vaccine supply chains to everyone in the vaccine world", even the most effective vaccine cannot have any impact on human health without a properly functioning supply chain. Understanding and addressing this system is critical to ensuring the full impact of vaccines. Everyone involved in vaccine decision-making plays a role in this system, from manufacturers who develop and package the vaccine to funders who finance the vaccines to policymakers and public health officials who help ensure a healthy population. For each of these groups, taking the supply chain into account can guide informed decisions about the design of vaccines and vaccine programs to better match the system.


Focusing extra attention on supply chains has led to advancements in other industries. Many companies in the food and retail industries employ or consult supply chain experts regularly to ensure that their supply chains run effectively and efficiently. Additionally, product design often occurs with supply chains in mind. The packaging, size, shape and composition of the product facilitates its storage and delivery. Examples include furniture stores developing pieces that can be shipped in component parts more r eadily and food manufacturers adding preservatives and developing dried and compact versions of food.

By contrast, evidence suggests that vaccine supply chains have not received the same degree of extra attention. Studies have shown that many vaccine supply chains around the world have substantial constraints and bottlenecks and are not delivering vaccines to many of the people who need them. Supply chain issues have hindered efforts to control, eliminate or eradicate diseases such as polio and measles . While supply chains in many low and middle income countries may have the most substantial problems, many vaccine supply chains in high income countries face challenges as well.

Why is computational simulation modeling needed to better understand vaccine supply chains?


Unaided by technology, humans can struggle to appreciate and understand complex systems. Modeling is essentially using mathematical equations or computational programs to represent the components, relationships and processes in a system. A computational model can then serve as a "virtual laboratory" to help better understand how a system operates and test the effects of different changes within the system. Using data and information on storage, transport, vaccines and personnel along with data on how these factors work together, a user can use our HERMES software to create a computational simulation model that represents all of the components and processes of the vaccine supply chain to help users view the system as a whole. Without this computational system, it is far more difficult to diagnose system vulnerabilities, coordinate operations, develop solutions and anticipate the impact of changes in the system or new technology. HERMES can project what may happen if things stay the same or circumstances change so that appropriate modifications can be made.

What is the vision of HERMES?