Vaccine Transportation: Maintaining a Successful Cold Chain Without Reliable Electricity (Part 2)

Keeping vaccines refrigerated when they’re delivered to the most remote parts of the world is a critical challenge that many experts have been trying to solve for decades. Dr. Harvey Rubin is one of the experts who have crafted new alternatives to address the issue.

Energize the Chain

Dr. Rubin is the Director of the Institute of Strategic Thread Analysis and Response at the University of Pennsylvania. Motivated by the millions of children who die from vaccine-preventable diseases every year, he and his colleagues developed an idea that materialized into a non-profit. Energize the chain has revolutionized cold chain logistics in Zimbabwe (http://www.energizethechain.org/our-team/).

On September 27, 2014, Dr. Rubin was a speaker at an independently organized TED event (watch here: https://www.youtube.com/watch?v=B6STcFfKFVU). During his presentation, he pointed out that there are more cellphones in the world than toothbrushes; and the industry grows exponentially, especially in the developing world. Phones work with electricity from cell towers, and Dr. Rubin explained how excessive amounts of electrical power produced from cell towers is always available, even in the most remote areas of the world.

Dr. Rubin believed if the private (mobile phone industry) and the public sector (health ministries) established partnerships, the power from cell towers could be used to sustain vaccine refrigerators. The refrigerators could be co-located in the cell towers. Back then he realized that it was doable; the technology worked and it was available. He established his refrigeration project in Zimbabwe and so far the non-profit has installed over 110 refrigeration sites in Zimbabwe and is expanding to other countries, like India. In one year Energize the Chain vaccinated over a quarter of a million children using refrigerators run by cell power. Dr. Rubin estimates that by 2016, the nonprofit will manage to vaccinate approximately one million children.

Temperature Monitoring Technologies

The function of the cold chain is to keep vaccines properly refrigerated throughout their journey. With difficult climates, unreliable access to electricity and poor transportation infrastructures, temperature monitoring becomes critical to ensure the success or failure of any given cold chain.

Monitoring temperature has evolved from the process of vaccine vial monitoring (VVM) to the most recent monitoring technologies. Vaccine vial monitoring was developed in the 1980s and consisted of a sticker that changed colors when the vaccines had been exposed to temperatures out of their recommended range. Still today, VVMs are widely used in developing countries and most of their immunization programs. According to estimates from the PATH (http://sites.path.org/vpsse/cold-chain-innovations/temp-monitor/) “between 2002 and 2012, VVMs allowed health workers to recognize and replace more than 860 million doses of inactive vaccine and to deliver 1.45 billion more doses in remote settings—helping to save more than 150,000 lives and reduce morbidity for countless others.”

Some of the most relevant innovations for monitoring temperature include:

Sending alerts to mobile phones

Monitoring devices nowadays allow users to select a specific temperature range; and the devices are programmed to send out alerts (whether it’s a phone call, a text message or even an email) to one or many people who are in charge of supervising temperature-sensitive vaccines. SmartSense’s system provides monitoring every 5, 15, or 60 minutes and sends out multiple and continuous alerts if the temperatures fall out of range. Continuous temperature reading makes it easier and more reliable to determine when and for how long vaccines have been exposed to unadvised temperatures.

Continuous monitoring without electrical power:

In places where power outages are very common, it becomes very difficult to figure out whether the integrity of the vaccines has been compromised or not, specially if the monitoring device stops working at the same time the refrigerator does. SmartSense's system keeps recording temperatures and sending alerts when the temperatures fall out of range for up to 24 hours after a power outage; however devices with expandable batteries are also available upon request.

The key takeaway of this series is learning how cold chain logistics play a key role in determining the effectiveness of vaccination efforts. Knowing that the inequality in terms of access and use of electricity faced by many developing countries should be addressed; and more comprehensive, practical, low-cost, and accessible solutions should be sought to deal with the challenges they face.