The story of a time and temperature indicator that has dramatically changed the course of vaccine
management practices as well as shaped the future of the cold chain.


It is not an overstatement to say that VVM is one of the most important recent innovations in the area of public health, providing health workers with advisable and dependable means of ensuring that the administered vaccine has not been damaged by heat. Without a VVM, the only reference available at point-of-use is the expiration date. But, if a vaccine has not expired, does this mean it is always safe to use? Vaccines exhibit no visible change with exposure to heat. Before the development of the VVM, health workers had no means of identifying whether vaccine had suffered damage from heat exposure at any point during transportation and/or storage.

VVM renders immunization operations much more effective. It allows programmes to exploit the stability of each vaccine to the greatest possible extent, it minimizes distribution costs, and it increases flexibility in the handling of vaccines in the field.

Nowadays the administration of safe life-saving vaccines is much less a matter of chance. With VVM, health practitioners in the field can focus on delivering an efficient care and treatment service without needing to be concerned about medicine viability.

Immunization outreach is also boosted with immunization access and coverage increased. VVM helps to pinpoint cold chain problems and facilitates the efficient management of vaccine stocks. Countries adopting VVM-based vaccine management can now make informed decisions with the help of VVM readings.

Although VVM was developed as a time and temperature integrator, it also made a significant contribution to the reduction of inadvertent vaccine freezing. VVM facilitated the extension of the cool-chain concept by removing the ice that is a common source of freeze damage. This helped health workers to better understand the heat stability of vaccines and accept the fact that freezing is a greater danger than mild heat exposure.

Today, VVM continues to evolve to address emerging needs in immunization programmes. Incorporating a threshold indicator into VVMs (VVM+) and integrating VVM into 2D barcodes are the most recent examples of this evolution. This simple, yet elegant tool, which has sold over eight billion units by 2018, has played a decisive role in saving millions of children’s lives saved across the planet.