Vaccine Transportation: Major Challenges and Alternatives
“Most men would rather deny a hard truth than face it.”- George R. R. Martin
These words of the famous author summarises the attitude of the supply chain sector towards the vaccine transportation and last mile delivery challenge. Over 25% of vaccines go waste globally, of which only 11% includes the open-vial vaccine wastage rate, rest of the wastage happens when the vaccine loses its potency before the vials were opened. As per the report on vaccines spoilage by Associated Press, of all the wastage in a fiscal year, 62% wastage happens due to spoilage of vaccines, and to the industry it costs more than $ 20 billion in a year. (http://www.nbcnews.com/id/22100133/print/1/displaymode/1098)
As per Dr. Lance Rodewald, Director of Immunization Services at the Centre for Disease Control and Prevention in Atlanta, the biggest problem, causing vaccine wastage, is improper refrigeration including the inefficiency of cold chain, which makes it hard to identify early and even harder to rectify, since if it goes unnoticed, the patient receiving the vaccine is still prone to catch the disease.
To address the issue of efficiency in cold chain, for over the last four decades, immunisation programs across the world have been transporting vaccines using insulated containers. The containers use frozen ice packs for maintaining low temperatures, and the problems associated with them were conveniently ignored since no other alternative was available.
The major issues for the transportation system, in which insulated boxes with ice packs were used, are mentioned below:
- Vaccine Freezing: The vaccine loses its efficacy if the temperature goes down below 2°C or commonly known as freezing of vaccines. Conventional solutions use thermocole (EPS) along with ice packs in the frozen state. Ice packs freeze below 0⁰C and therefore ice packs kept in the frozen state increases the risk of temperature falling below 2⁰C. Usage of Ice packs directly risks the degradation of vaccine due to freezing, which if unnoticed, could lead to serious health consequences in the patient.
- Complex validated packaging solutions: The validated packaging solutions available in the market are too complex with standard operating procedures running into pages, which make the operations very difficult and therefore vulnerable to mistakes.
The need for conditioning the Ice packs and providing it the sweat time also leads to the biggest concern of performance. Since the conditioning criteria involve keeping the ice packs for a particular duration at room temperature, the human error margin is very high. Another factor is the difference in ambient temperatures across the globe, which makes the standard room temperature maintenance extremely difficult for operations and therefore variance in conditioning of ice packs. The conditioning of ice packs is never accurate because of these factors leading to temperature excursions.
Moreover, the current solutions need ice packs or coolants to be kept at either -20⁰C, +5⁰C or +15⁰C depending on the temperature requirements. This means an infrastructure requirement of a deep freezer, refrigerator and a cold room. Also complexity in packaging since it is usually a combination of ice packs conditioned at different temperatures placed in a particular order.
We have made it too complex for the pharmaceutical and logistics companies!
- Diversity in weather: The weather in India has its ups and downs on the extreme sides, including prolonged summers as well as extreme winters. These weather conditions affect the shipment of vaccines directly. Since extreme summers could cause the ice packs to melt faster and the backup duration dips down substantially, risking the exposure of overheating to the vaccines. Similarly, during winters the same box, conditioned in the same way, will cause the temperature to dip lower than 2°C, causing the freezing of vaccines.
- Placement of Data Logger: To measure the real time temperature, generally a data logger is placed inside the product box to measure and record the temperature for the complete duration. However, where does one place the data logger – bottom, centre, top, right beside the product or somewhere else? An ideal packaging solution should give similar temperatures across the box (Since the product can be placed anywhere in the box) irrespective of where the data logger is placed. WHO suggests a diagonal placement of data loggers to measure the uniformity in temperature:
- Bottom right/Bottom Left
- Top Left/Top right
Currently, most packaging solutions in the market would suggest that do not place data loggers on the side but at the centre. However, this should actually be immaterial.
To address the issues, UNICEF suggested under the “Last Mile” Project, that Phase Change Material could be a potential solution for overcoming existing limitations and effectively maintaining the cold chain throughout transportation.
Phase Change Materials (PCMs) are special thermal energy storage materials which store or release large amount of thermal energy while changing phase from solid to liquid or vice-versa at a particular temperature.
PCMs can be engineered to work at a variety of temperatures as compared to ice packs which work only at 0⁰C. PCMs bring in the precision in temperature control critical to the Pharmaceutical Cold Chain.
Pluss has recently launched Celsure™ – a unique PCM based shipping solution for Pharmaceuticals. Celsure™ is a patent pending technology, designed and developed by Pluss, which uses savE® Phase Change Materials combined with high density EPS insulation to give a precise temperature control (2-8⁰C or 15-25⁰C) for a period of more than 96 hours.
The design of Celsure allows it to provide the following advantages to the user:
- Single step conditioning (Place the PCMs directly from the freezer)
- Guaranteed temperature maintenance even at ambient greater than +40⁰C (2-8⁰C or 15-25⁰C)
- Easy and simple to use with only one type of conditioning and one size of PCM cassettes
- No requirement of different kinds of cooling equipments or cold room. Just one freezer at -20⁰C
- More than 96 hours of back up
The world is advancing with technology and so is the complexity of the challenge to maintain healthcare. The need of fighting diseases in advanced ways is only going to grow, which means an effective cold chain is required to meet the need of the hour. Celsure™ with the help of Phase Change Material technology and unique design addresses the current issues of the Pharmaceutical Cold Chain. The challenge now is breaking the inertia in the industry to switch to a simpler and more effective solution.