FORT LAUDERDALE (CBSMiami/AP) — Members of the Florida National Guard have started on-the-spot testing of residents at nursing homes for the new coronavirus as long-term care facilities in the state have reported scores of cases.

Guardsmen have conducted tests of residents and staff at nursing homes in South Florida and UF Health Shands has done other spot-testing at facilities, DeSantis said.

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“We want to continue to do that, given that is the most high risk population,” the governor said.

In Clay County, in the Jacksonville area, 49 cases have been reported at long-term care facilities, and 51 cases among residents and staff have been reported at a nursing home in Suwannee County, located halfway between Jacksonville and Tallahassee.

Statewide, there were almost 840 coronavirus cases in residents and staff at long-term care facilities, as of Saturday.

Last month, DeSantis ordered a suspension of all visits to nursing homes, assisted living facilities and similar sites across the state.

As of Saturday evening, Florida had about 19,000 coronavirus cases and at least 446 deaths.

The governor also said Saturday that the state Department of Health has ordered serology tests that can detect coronavirus antibodies in people who aren’t currently sick.

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“There may be people who had an illness in February or March and didn’t go to the doctor for it, and maybe they think, ‘Maybe I had it,'” DeSantis said. “You can also spot-check and see a representative sample to see how many people in our society have the antibodies.”

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Separately, the governor said a stay-at-home order and the resulting reduced traffic had provided an opportunity to speed up construction on central Florida’s biggest infrastructure project: the expansion and refurbishment of Interstate 4, which stretches from Daytona Beach to Tampa.

A stretch of the interstate highway that goes through the Orlando area is in the middle of a $2.3 billion overhaul. The speed-up could allow the project to finish one or two months earlier than planned, DeSantis said. Portions of the highway that usually get more than 100,000 cars a day are now seeing 40,000 cars.

“We should take advantage of this pause,” DeSantis said. “The fact that we don’t have as many people on the roads, let’s take advantage of that.”

DeSantis also announced Saturday that 32,000 laptop computers are being distributed to 34 small and rural school districts around the state so that children can participate in their classes online.

At Walt Disney World, union officials said Saturday that Disney plan to stop paying wages to 43,000 workers in about a week while allowing them to keep their benefits for up to a year in what is the largest wave of furloughs since the theme park resort closed in mid-March because of the new coronavirus spread.

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(© Copyright 2020 CBS Broadcasting Inc. All Rights Reserved. The Associated Press contributed to this report.)