For the second time this year, Nasdaq has shut its Philadelphia options-trading floor as the pandemic resurges, another sign that the virus is not under control.

The trading room, at Nasdaq PHLX’s facility in the FMC Tower on the west bank of the Schuylkill in University City, “will temporarily suspend open outcry trading and operate fully electronically as a precautionary measure related to COVID-19,” Nasdaq told employees in an alert Wednesday.

“Philly Covid numbers [are] skyrocketing,” Nasdaq spokesman Joseph G. Christinat said in an email.

The market hopes to reopen sometime in December after testing staff and traders who use the facility and taking additional precautions.

Nasdaq previously closed the trading area in March, sending 200 bright-jacketed traders and support staff to work from home or trading company offices. It reopened in June after adopting safety and cleaning measures.

The Philadelphia floor is one of the few places in the United States where securities buyers and sellers are still matched by live trading specialists and “open outcry” brokers who yell orders into a small crowd of fellow traders until they accept or reject deal prices.

Others include the New York Stock Exchange trading floor in Lower Manhattan, for stocks, and the Chicago commodities futures markets. Those markets, which closed in March and reopened in late spring, have not announced new closings.

While most trades at U.S. exchanges have occurred online since the 2000s, some market players insist they get better service for specialized orders, for example large bets on options contracts that attempt to lock in future gains, by dribbling the put and call (buy and sell) orders through live brokers instead of dumping them electronically into the anonymous electronic markets.

The Philadelphia exchange, the nation’s oldest, was purchased by Nasdaq in 2007 for $652 million and, with its technology unit, was expanded to consolidate all of Nasdaq’s options and futures business.

The market, which has moved around the city several times since its founding in 1790, most recently moved from its basement location at 1900 Market St. to three floors of the FMC tower in 2017.

In its options-trading heyday of the 1980s and ’90s, hundreds of members traded options in world currencies, Dell Computer, and other popular options contracts. The market has served as an incubator for Philadelphia trading and technology businesses, such as Susquehanna International Group, the multibillion-dollar trading and investment company based in Bala Cynwyd, which traces its roots to the Philadelphia exchange trading floor.