Vu Minh Huong

Vu Minh Huong works to deliver vaccine to babies—fast.

Can we stop good vaccines from going bad?

To have the best chance of saving a child from potentially deadly infection caused by hepatitis B, you must administer hepatitis B vaccine within 24 hours of birth. Not only must the vaccine be delivered promptly, it must be kept at a stable temperature to remain effective—a challenge when vaccines must travel long distances under varying conditions.

The “cold chain” is a system that keeps vaccines at controlled temperatures while they’re stored and transported. Maintaining the cold chain is one of the most critical—and challenging—parts of delivering vaccines. Project Optimize, a joint project of the World Health Organization and PATH, is collaborating with the government of Vietnam to test and apply technological advances to improve vaccine delivery systems—from the cold chain to logistics and tracking—so that children have the best chance at being protected from diseases.

Vaccine on ice

Dr. Vu Minh Huong, PATH’s senior team leader for vaccines and immunization in Vietnam, tells how Project Optimize is addressing the quandary of hepatitis B in his country:

“Parents tell me how much they want the [hepatitis B] vaccine to protect their children.”

The number of mothers who pass hepatitis B to their newborns during delivery is high in Vietnam. Infected infants are much more likely to become chronic carriers of the virus, which can cause liver cancer later in life. There is no effective treatment for hepatitis B. Fortunately, you can prevent mother-to-child transmission with a birth dose of vaccine. Unfortunately, it can be difficult to reach newborns in time.

Most routine vaccinations in Vietnam are given at a commune health center on one day per month. These small, local health centers often lack reliable electricity or refrigerators for storing vaccines. Shortly before the vaccination session, the commune health worker travels up to 50 kilometers to the district health center, where the vaccine is kept in a refrigerator, and carries it back in a cooler with ice packs. This system does not work for the hepatitis B vaccine, which needs to be stored nearby in order to be on hand when a child is born. And while hepatitis B vaccine needs to be kept cold, it can be damaged if it freezes when it sits on the ice pack.

A new way to store vaccine

Vu Minh describes how the nanoQ cooling device could help health centers safely store hepatitis B vaccine:

Through Optimize’s collaboration with Vietnam, we’re piloting a new passive cooling device named nanoQ, which could provide a way to store hepatitis B vaccine at the commune health centers. NanoQ uses state-of-the-art insulation materials and a unique configuration design in order to achieve appropriate temperatures for vaccine storage for longer periods of time. Another advantage of nanoQ is that it never gets down to freezing temperatures.

Using the sun to cool

The sun powers another option for safe storage, says Vu Minh, helping get vaccines to the children that need them:

We’ve also installed two solar-powered refrigerators in district-level health centers, where electricity can be unreliable and expensive. They worked so well during the initial months that the Vietnam’s manager of the National Expanded Program on Immunization recommended that they be used for regular vaccine storage in those centers.

I’ve had many chances to see children infected with hepatitis B since I began working for PATH in 1997, and parents tell me how much they want the vaccine to protect their children. I also understand how challenging it is for commune health workers to make an extra trip to the district health center to get the vaccine, especially in mountainous areas or during the rainy season. My colleagues and I are working hard to find solutions to protect newborns from this deadly infection, and we’re optimistic that we are succeeding.

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Photo: PATH/Nguyen Phu Cuong.