Vaccine Cold Chain Technologies
Even from the simplistic representation, we regard the vaccine cold chain as a sophisticated network of distributors and manufacturers, reliant on organization, responsibility, and best practices to meet their goals. Most of all, the implementation of sophisticated cold chain technology (refrigeration systems, GPS devices, and temperature monitoring solutions to name a few) is also important to improve old ways, eliminate bad practices, and maintain quality of the transported vaccines. Despite technological advancements, many of these bad practices still exist. Without these technologies, a vaccine may be exposed to a number of hazardous conditions or inadequate practices. In the steps to the 'Child and Mother', there are many important 'points' by which the chain can be broken.
Unfortunately, while many larger and more prominent "chains" have the financial means to implement scalable and comprehensive technology solutions (from manfucturer to patient), many bad practices and inadequate technologies remain in the industry. The CDC administers over $3 billion worth of vaccines to lower income families through the VFC (Vaccines for Children) program each year, and with that said, the vaccine cold chain plays an important quality control (and assurance) role in this program.
There are several issues to consider for vaccine cold chain technologies, and one of the most prominent issues is the lack of adequate temperature monitoring solutions. On the surface, vaccines stored outside the sensitive 2-8°C range can become ineffective if exposed for an extended time period. A recent analysis by Vaccine made an estimate that 14-35% of vaccines are subjected to variable storage temperatures during delivery. There are several concerns that arise out of this analysis; the costs associated with manufacture and delivery are wasted, delivery of vaccines may be delayed, but most importantly, the actual recipients may be given a comprised vaccine, or worse, one tainted with bacteria.
Given the strict 2-8°C compliance for most vaccines, the focus shifts to the monitoring technologies within the refrigerators or freezers. A refrigerator unit must be monitored from several different points to avoid confusion with common cycles and processes. These may include refrigeration cycles, air circulations patterns, use patterns, environmental conditions and defrost cycles. All of these processes can negatively affect the accuracy of a temperature monitoring device. With that said, the proceeding paper log is a familiar (and troublesome) sight in the vaccine cold chain and highlights the need for a robust temperature monitoring solution.
There are many advantages that electronic data loggers (or temperature monitoring devices) bring to the vaccine cold chain. There are several devices that provide a low-cost, high-performance solution for temperature monitoring and the benefits are tremendous when juxtaposed with the beleagured logging chart.
Continuous monitoring: All changes are captured, logged and can be accessed at any time.
Simplicity: These devices are easy to use, easy to install and provide a high level of accuracy.
Results: Data is quickly calculated and can be analyzed instantly, often from a cloud portal or GUI-based software.
Alarm Capabilities: E-mail notifications, text notifications, phone calls, and user-defined networks for alerting cold chain personnel
Glycol/Sand Sensor Buffers: Provides an estimate of properties/mass of vaccine and allows accurate temperature measurements for the vaccines.
For further reading on evaluating and installing temperature monitoring devices for the vaccine cold chain, we recommend this guide on Temperature, Pressure, and Flow Metrology from the National Institute of Standards and Technology (NIST).