Watch how an inventor launches her life-saving device in The Big Idea: Last Mile

When cryogenics expert Kitty Liao discovers that half of the world’s vaccines spoil before they can reach those who need them, she invents a solution.

By Leigh-Ann Jackson — August 22, 2023


Watch how an inventor launches her life-saving device in The Big Idea: Last Mile

When cryogenics expert Kitty Liao discovers that half of the world’s vaccines spoil before they can reach those who need them, she invents a solution.

By Leigh-Ann Jackson — August 22, 2023

In 2014, while participating in a humanitarian hackathon in Geneva, engineer and physicist Kitty C. Liao read a statistic that shocked her. That year, more than 18 million children around the world were reportedly unvaccinated.

But it wasn’t a matter of supply. Rather, it was a crisis in logistics that was largely to blame. 

Due to cold storage delivery issues in many developing countries, children in rural communities are not getting basic vaccinations to protect  against preventable diseases such as polio, yellow fever, and measles. In some remote regions, healthcare workers must transport vaccines by boat, motor bike, or on foot — and, sometimes all three. They are often using storage containers that make temperature control difficult, if not impossible. Spoilage can occur when the lids of so-called “cool boxes” are repeatedly opened over extended periods of time, are packed incorrectly, or simply can’t stay cold long enough to reach kids living far from infrastructure. 

“One of the biggest issues is human error,” the UK-based Liao says. “We know that a functioning device can still fail when it’s not used properly and this is exactly what happens in the field.”

WATCH The Big Idea: Last Mile | MIT Solve

Cryogenics expert Kitty Liao tackles the crucial 'last mile' of transporting vaccines to those who need them most.

After researching the issue further, Liao — who has a cryogenics background and worked as a physicist fellow at international nuclear research hub CERN — dedicated her life to solving this problem. Her goal is to launch a reliable cooling device to help ensure successful vaccine delivery to underserved communities around the world.

From a humble sketch, she developed the prototype for the last-mile vaccine cooling system, which she called SMILE (SMart last-mILE). The device is an all-in-one backpack that features a rotating drum and air-locking technology that keeps the vaccines at the optimal temperature for up to four days — much longer than typical coolers lasting only a few hours. 


Learn more about HP’s digital equity partnership with MIT Solve and see the other films in The Big Idea series. 


From Cambridge to Cameroon

In The Big Idea: Last Mile, a Redglass Pictures film presented by MIT Solve and made with support from HP, we follow Liao’s quest to get her potentially life-saving invention out into the world, including her struggle to find backers and build case studies. She tests her device in real-world conditions in Cameroon, where healthcare outcomes in rural settings are much poorer than urban ones. In Africa overall, about 16% of rural villages do not have mobile vaccination programs because of a lack of transportation infrastructure and more than half of rural health centers experience vaccine shortage, according to Journal of Global Health Reports research on childhood vaccine uptake in Africa.

Last Mile is one in a trio of short documentaries that follow three innovators who are brilliant, bold and united by the desire to use technology, science and engineering to create radical change. 

Now the CEO of her own humanitarian engineering company, Ideabatic, Liao has spent the last few years seeking funding to manufacture more SMILE devices.

It’s been an uphill battle.

“There hasn’t always been a lot of interest,” she confides. “The users in the field love the device. However, they don’t decide what to buy.” 

Kitty Liao handling the last-mile vaccine cooling system, SMILE.

MIT Solve

Kitty Liao works on her vaccine cooling backpack system, SMILE.

She got a much-needed boost after applying to the MIT Solve Health Security and Pandemics Challenge in 2021. Solve’s mission? To globally source tech-based social entrepreneurs who are tackling the most pressing challenges in their community. As a selected innovator, she received $10,000 in grant funding, and in addition to finding an encouraging mentor, she connected with other innovators who shared her vision to make the world a better place. 

“Meeting a lot of social impact founders at MIT Solve was probably the most valuable,” she says. “It feels incredible that there are other people who think the same.”

Liao, along with the female social entrepreneurs profiled in The Big Idea films, saw their prospects change after being named part of MIT Solve's cohort of innovators. 

“We're like matchmakers for superheroes — teaming up tech-savvy problem-solvers with folks who can help their brilliant ideas fly,” says Solve’s Executive Director Hala Hanna. “Their stories are not only inspirational,” Hanna says, “but are also a testament to the potential of technology when combined with an unwavering commitment to social impact.”

The future of SMILE

Liao is currently supervising students who are working on research and development projects to upgrade the SMILE device. Her big-picture aim is to widen the device’s impact in low- and high-income countries alike. After her field tests, the government of Cameroon has since ordered more than 2,700 of her SMILE devices for deployment, but she’s still looking for funding to manufacture them.

“I never thought that my story would be made into a film,” she says. “I’m hoping we will be able to raise awareness and also use this as an opportunity to get closer with those who actually care about these issues.”


Read how MIT Solve connects startups with funding and resources to solve global challenges through social impact innovations.


A pillar of HP’s Sustainable Impact goals is to accelerate equitable access to those who have been historically excluded so that they can participate, benefit from, and thrive in a digital economy. HP supports and champions those, like Liao, using technology to make the world a better place. 

HP is a longtime sponsor of MIT Solve, providing focused support, prize funding, and sponsorship to social entrepreneurs advancing digital equity and sustainability solutions in their communities.