Some businesses that were shut down by the pandemic are now making changes the help join the fight against the coronavirus.

East Farmingdale-based D'Addario is world-renowned for its guitar strings and other instrument accessories. After the pandemic rendered the factory silent, the company has repurposed and kept moving.

The same machines that make top-of-the-line drum heads are now churning out medical face shields. The company says it brought back a dozen workers, and eventually wants to deliver 100,000 face shields a week.

Young adults and students shop, deliver grocery items to Nassau seniors 

The first batches went out this week to Long Island hospitals in need of supplies.

In Wyandanch, Corinthian Cast Stone usually makes architectural elements for buildings, but it's now making lightweight plastic shields that cover COVID-19 patients as they're being intubated, protecting medical personnel from infection.

Cortinthian President Jason Hirschhorn says workers re-tooled high-tech machines to help design and manufacture the shield. Now he says he's getting orders from hospitals across the world.

For many employees, getting back to work was good, but some say what's really satisfying is that they're making something helping others.

"That is the important thing," says Chris Argila, of Corinthian. "Saving lives and doing what we can here."

Both companies say they've only been able to bring back a few employees, but eventually plan to bring back more workers to keep up with demand.