Harvard works with plastics supply chain to address swab shortage

In the coming weeks, clinics around the world will need millions of nasopharyngeal swabs for coronavirus testing. But the specialized swabs are complicated to make, and hospitals and regulators worry that current suppliers can't keep up with demand.

But two U.S.-based plastics companies are playing a key role in addressing the shortage.

Researchers at Harvard University, working with health care, researchers and plastics supply chain partners, have designed a new fully injection molded swab that can be manufactured inexpensively and at high volumes.

The team went from design to large-scale manufacturing in just a few weeks.
Nasopharyngeal swabs are the long Q-Tip lookalikes used to collect clinical test sample of nasal secretions from the back of the nose and throat.

The project began just over a month ago, when Beth Israel Deaconess Medical Center (BIDMC) in Boston contacted the Wyss Institute at Harvard University, asking for help to solve the hospital's swab shortage.

"It was an interesting project. Definitely far from what I typically do at Harvard," Richard Novak, senior staff engineer at the Wyss Institute, said in a telephone interview with Plastics News.

"Beth Israel Deaconess reached out to my boss, Dr. Donald Ingber, and they were saying, 'We're reaching out to everybody. We have this huge swab shortage. We can't test enough people. Can you help?'" Novak said.

At the time, there were already two major suppliers of the specialized swabs: Puritan Medical Products in Guilford, Maine, and Copan Diagnostics Inc. in Brescia, Italy. Puritan's swabs are made by Teel Plastics Inc. of Baraboo, Wis. But U.S. Food and Drug Administration officials were concerned that shortages of swabs could limit the health care sector's ability to test people for COVID-19.

The Wyss Institute's staff come from Harvard's Schools of Medicine, Engineering, Arts & Sciences, Design and Education, and they have a close relationship with BIDMC. The institute quickly pulled together a team of experts to develop and test the new swabs.

"We initially started by focusing on 3D printing, just because it's so easy to iterate designs with 3D printing. Obviously there are challenges in terms of the material properties, chemical properties to an extent, structural and also in terms of manufacturing," Novak said.

"But it did enable us to very quickly iterate several designs, and maybe in a week we had some designs that were passed through preclinical testing, which was incredibly fast," he said.

Most nasopharyngeal swabs consist of two pieces: an injection molded handle and an absorptive tip made of a soft material such as cotton, polyester or flocked nylon. Each swab is manufactured in a multistep process, then assembled, sterilized and packaged. The swabs are about 15 centimeters long — long enough to reach where the throat meets the nasal cavity.

The Wyss team's swabs featured a flexible, honey dipper-like design that could be made in one piece.

"We were able to eliminate all of those secondary steps and the supply chain issues that they can create," Novak said.

When large 3D printing companies began to churn out the swabs, Novak's team turned its attention to developing an injection molded version, which he knew would boost production and reduce cost.

That's where Protolabs Inc. of Maple Plain, Minn., came in.

"We reached out to Protolabs, which is a company that is one of those rare, rare breeds that can do injection molding even the next day," Novak said. "And it was really great; they worked over the weekend to get some samples out for us."

"Our business model is based on speed," said Gurvinder Singh, Protolabs' global product director for injection molding. "With this pandemic and the shortage of supplies, everything is required now, or even yesterday."

In a matter of days, Wyss had injection molded samples of four similar-looking swabs: one made of nylon, two from polypropylene, and one with a roughened surface. The Wyss team sent the prototypes to eight hospitals and health centers for preclinical testing.

Clinicians evaluated the swabs' performance, including their comfort, ease of use and ability to collect a large enough sample with detectable amounts of viral RNA.

Because of its ability to quickly develop injection molded parts, Singh said, Protolabs has been involved in a wide variety of COVID-19 projects, including face shields, personal protection equipment and ventilators.

"We have formed a COVID tiger team within our injection molding services," Singh said in an interview with Plastics News. The cross-functional team includes managers, application engineers and designers. They know the importance of getting coronavirus-related projects finished quickly.

"Like I tell the team, we don't have time for rebirth, we cannot iterate on it. Let's make sure we put our best foot forward," Singh said.

When they settled on the best design, it was time to ramp up production. That's where Innovative Product Brands Inc. of Highland, Calif., came in.

The company, known as IPB, is a contract manufacturer that was launched by President and CEO Bryan Tapocik in 2001. IPB has expertise in mass-volume precision injection molding, making products including toothbrushes.

Shane Nielsen, vice president of global sales, said IPB already made a similar product to the nasopharyngeal swabs.

"We make a micro brush that we sell millions of in the professional dental space. So that's where we have the expertise, we understand how it works; we understand plastics," Nielsen said.

IPB was able to quickly make two eight-cavity tools and start molding the swabs at one of its partner company plants in Guangdong, China.

"Richard and his team made our job really, really easy. We took the drawing, and then we made a couple of enhancements on the handle, the grip," Nielsen said.

In addition to the one-piece honey-dip design, IPB will also make a flocked swab and an oropharyngeal version.

As Novak predicted, the injection molded swab will be a fraction of the cost of a 3D printed version.

"With 3D printing, they were charging $3-plus for each individual swab. We can make millions of these for under a buck [each]," Nielsen said. "For the 60- to 70- cent range, they get a sterilized, individually wrapped swab that's ready to go.

"Once we go to commercialization, after these clinical trials, we will be able to do 200,000 a day, or 6 million a month. And as demand increases, we can build 16-cavity molds, we can go to 32-cavity molds, we are confident that we can grow with the demand," Nielsen said.

"It's been a great experience, and it's been humbling, to think that we're contributing to saving lives," he said. "Right now getting people tested seems to be a bottleneck, getting everybody tested that needs to be tested or wants to be tested. And, if we can save lives, that's a really, really cool thing."