In the 1960s and 1970s, the world was suffering in the wake of the spread of a number of infectious diseases, the foremost being smallpox, which, if not treated, could be fatal. By the mid-1960s, the World Health Organization (WHO) had launched a global campaign to eradicate the disease.
Unfortunately, at the time, there wasn’t existing knowledge around the best way to transport and administer large amounts of the vaccine. Professor David Morley of the Institute for Child Health in London was one of the lead voices to steer the initiative. He made a strong case for temperature monitoring by highlighting three critical issues.
- The absence of systems to monitor the temperature of thermosensitive vaccines.
- The absence of appropriate equipment to store and transport vaccines.
- The insufficient number of adequately trained staff to handle vaccines.
He presented these to the WHO and proposed that a team within the Expanded Program on Immunization (EPI) address them. Once they had attended to these issues, the organisation could establish the administration of routine immunisation services globally.
The first forms of temperature monitoring were implemented at large national medical stores using continuous temperature recorders. These used a rotating disk of paper on which an ink stylus left a mark which showed a record of the temperature.
This manner of temperature recording complied with standard procedures at the time and worked well in some cases. It was also easy to note when temperatures deviated beyond pre-set limits, but in many other cases, the temperature reports proved to be unreliable.
From the early stages, the WHO envisioned the need for an ‘end-to-end’ temperature monitoring system for vaccines in the cold chain. In the early 1980s, the Swiss-based company, Berlinger & Co. AG developed what was referred to as a cold-chain monitor card (CCM). This was included in shipments of vaccines from the manufacturer to the intended countries and monitored the storage temperature in the various facilities.
This CCM then evolved into a vaccine vial monitor (VVM). The VVMs are small stickers that adhere to each vaccine vial. These devices then change colour irreversibly as the vaccine is exposed to heat, thus enabling health workers to easily determine which vaccine vials have been compromised.
Twenty years after the development of its first monitoring device, Berlinger developed an electronic 30-day temperature monitor, the Fridge Tag. This monitor is now available as both a standalone recording device and a remote recording device providing alarms and data transmission with internet-based reporting. This electronic temperature monitor is so well developed that it has become the gold standard for monitoring vaccines in storage, globally.
Multi-channel temperature loggers with remote alarms and recording capabilities have also made it possible for pharmacists to respond quickly to temperature alarms and use the temperature data to analyse refrigerator performance.
At TMSA, we are very proud to be the sole distributor for Berlinger temperature monitors in Southern Africa. It is a privilege to be associated with this company that has have played an integral part in the development of temperature monitoring in the global pharmaceutical industry.