As the number of coronavirus cases rises worldwide--more than 43,100 as of Tuesday--U.S.-based businesses are playing a crucial role in the fight to limit the spread of the virus. These include companies that we've spotlighted here on the pages of Inc., including Inc. 5000 and Best Workplaces honorees, as well as mentors in our Founders Project. We asked Inc. CEOs to tell us about their part in the battle, and the responses flooded in. Here are just a few of the stories we heard. 

Lighthouse Lab Services

Before a clinical lab can test for illnesses like coronavirus, it needs to be properly equipped, staffed, and validated. Lighthouse Lab Studios can provide all of that, and last year it booked $5.1 million in revenue, making it No. 4,341 on the 2019 Inc. 5000. One machine the company sells is the Thermo Fisher QuantStudio, which can test for the presence of coronavirus using a nasal or cheek swab. Unlike old methods that use cultures and take three to five days, the machine can produce results in three hours. The company has received a number of inquiries from both current and potential customers asking about getting equipped and validated for coronavirus testing, says Jon Harol, founder and CEO of Lighthouse, which is based in Holly Springs, North Carolina. So much so that the company recently debated whether to dedicate a branch of its business to the virus. The verdict: not just yet. "But we have our finger in the air," Harol says. "If it started to spread in the U.S., and we see a demand for testing, I think we're in position to pivot into that pretty quickly."

Xenex

Xenex makes a robot that disinfects hospital rooms and labs using light from a xenon lamp. The robot, called LightStrike, flashes high-intensity ultraviolet light that deactivates the DNA of pathogens including viruses, bacteria, and fungi. A two-minute LightStrike cleaning cycle eliminates 72 percent more pathogens than a manual cleaning, according to a 2018 study by MD Anderson Cancer Center. The robot is already being used in more than 500 hospitals and labs, including the Mayo Clinic and London's Kings College Hospital, says Xenex CEO Morris Miller. While the company hasn't yet been able to test against the coronavirus specifically--it could be months until there are samples available for testing--Miller says it will be effective since the LightStrike is a full-spectrum device, meaning it operates in every light wavelength in which pathogens live. Concerns over the coronavirus have led to an uptick in business for Xenex, with several hospitals using their emergency funds to buy one or more of the $100,000 LightStrike robots. Miller founded the company in 2008 in San Antonio, Texas, and recently served as a mentor in Inc.'s Founders Project.

Zogics 

Zogics sells gym equipment--but not just barbells and cardio machines. The company also sells cleaning products like disinfectant wipes, hand sanitizers, and electrostatic sprayers used to decontaminate facilities. The company has seen a 50 percent increase in sales of its wipes and sanitizers in the 30 days ending February 10 compared with the previous 30 days, according to founder and CEO Paul LeBlanc. Sales of its electrostatic sprayers, which have demonstrated effectiveness against viruses similar to coronavirus, have seen a 300 percent increase. And it's not only gym operators that have come calling. "We've seen a sharp increase in sales for disinfecting products going into office buildings, schools, recreational facilities, first responders, and the military," says LeBlanc. Lenox, Massachusetts-based Zogics came in at No. 3,759 on last year's Inc. 5000 list with $10.2 million in revenue, and was named one of Inc.'s Best Workplaces in 2019.

Georgetown Home Care

Georgetown Home Care provides care to seniors, particularly those who have just left the hospital, which places its clientele firmly in the most at-risk population. So it's highly practiced at precautions against the flu and other transmittable diseases. The CDC has warned that, as with the flu, the elderly and anyone with underlying health conditions are at higher risk of death when it comes to the coronavirus. The Washington, D.C.-based company recently met with the D.C. Department of Health to discuss best practices for preventing the spread of the illness. Georgetown now is taking the extra step of keeping employees who travel outside the U.S. off of home visits for several weeks after they return. "We've had calls from clients asking, 'Do I have to worry about coronavirus?' " says CEO John Bradshaw. "We tell them that if they want, we're happy to send them the paperwork we're giving to our caregivers to show them what kind of precautions we're taking." Those precautions involve lots of hand-washing and cleaning of surfaces, things the company already does to defend against the flu. Georgetown generated $5.7 million revenue in 2018 and finished No. 2,501 on the 2019 Inc. 5000.