Costello researched hospital-acquired infections and realized how pervasive this problem is: "It is the No. 1 patient killer in the United States," she said.
Not only are these preventable illnesses dangerous, they are expensive. Infections like MRSA, E. coli and C. difficile, cost the U.S. health-care system around $30 billion a year, according to the Department of Health and Human Services.
Costello teamed up with James Peterson, an aspiring mechanical engineer and one of her college friends at Rensselaer Polytechnic Institute. After forming the company in their senior year, they spent 18 months developing a product that could help. They figured how to manipulate light to create a technology that does not harm humans.
Hospitals already use ultraviolet lights to kill germs, but UV can't be used around people for prolonged periods of time, since it can cause damage to skin cells. Also, UV lights bathe an entire room in a disco blue color and who wants to be in a blue room? "There's nothing out there that continuously cleans in the marketplace," Costello said.
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During their research they found studies that showed blue-violet LED lights had a different effect on certain bacteria, which have molecules that humans don't have. When the light hits those molecules, it causes a chemical reaction, producing toxic oxygen. So much oxygen is created that it effectively blows up the bacteria.
Costello and Peterson got the bright idea to use a mix of LED lights to create a commercially desirable solution. They were able to develop innovative software, which produces white light. They can even tweak the white levels to make them softer or harsher depending where they're being used.
Vital Vio just started selling the lights this fall and in New York City, Mount Sinai Hospital is testing the product. Fran Wallach, who is an infectious disease specialist at Mount Sinai, says the applications for the product could reach well beyond hospital rooms. "It could potentially have a huge impact because of all the public spaces … public restrooms, airplanes, subways, public spaces in general would be an ideal fit for a product like this," Wallach said.
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Mount Sinai expects to publish results in a medical journal by spring showing how the lights are performing. Wallach is excited about the technology, but she said the lights won't replace hand-washing and standard cleaning. Still, she welcomes the new technology.
"I don't want to put a completely positive spin on things until we actually know what the data shows. We have the assumption and the hope and initial view that there is a pretty good effect, but wait till we have the numbers," Wallach said.
The lights have already been tested at the Wadsworth Center, the New York state Department of Health biodefense lab. The product is registered with the EPA and it is certified by Underwriters Laboratories.
Vital Vio is also in talks with major health-care providers on both coasts.
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The company's staff of 10 is expected to increase to 15 employees in January and while it is making the lights by hand now, it expects to enlist a large-scale manufacturer in 2015.
At only 24 years old, it's safe to say Costello probably has a pretty bright future ahead: "Our alma mater's motto is 'why not change the world?' And we took that seriously and we don't see why not? Why we should stop anywhere along the path?"