Should a possible case of COVID-19 (the novel coronavirus) occur in Southern Nevada, health officials will be able to test for the disease without sending specimens to the Centers for Disease Control. But unlike health departments in many other metropolitan areas, the Southern Nevada Health District will not announce the number of tests in progress, but rather only those with positive results.

“That ‘s the way we operate,” says Dr. Fermin Leguen, acting Chief Health Officer of the SNHD. “We discuss confirmed cases. We don’t discuss anything else.”

But last month the SNHD announced it was awaiting test results for a patient who had returned two weeks earlier from China. The patient tested negative, according to the health district.

“Because this was an evolving situation and we were trying to be responsive to the requests and inquiries we were getting, we did provide the information initially,” SNHD spokeswoman Jennifer Sizemore told the Current.

Leguen says he has no information on the frequency of false-negative results for the test kits obtained by SNHD.

“I don’t have that information. I would have to ask the CDC,” Leguen says.

The CDC did not immediately respond to inquiries.

A high rate of false-negative tests has complicated efforts in China to get a true grasp on the extent of the outbreak. As of Tuesday, more than 1,000 people have died from the virus – mostly all in China — and more than 43,000 are known to be infected.

“Even patients who definitely have the disease only come back positive 30 percent to 50 percent of the time,” Professor Wang Chen, an expert in critical diseases and director of the Chinese Academy of Medical Sciences, told the Strait Times. “Testing throat swabs (from potentially infected people) also returns a lot of false negatives.”

Delays in diagnosing and treating the disease are extended not only by false-negative tests, but also by the nature of the virus.

“A person can have no antibodies today and tomorrow be positive,” says Leguen. “The level of pathogens was not enough yesterday to make the diagnosis and today that germ has multiplied.”

Is the conventional flu, which kills thousands of Americans a year, a bigger risk than coronavirus?

“If you look at today in the U.S., there are thousands of flu cases every day and every certain number of days you have someone die in the community. It’s already established. It doesn’t bring the level of uncertainty that this new virus brings,” says Leguen. “I wouldn’t say the flu is more of a threat than coronavirus. It’s just that coronavirus has not established itself here yet.”

Add to that the unknowns, such as a new study indicating the incubation period for the coronavirus could be as long as 24 days.

“So far, to my understanding, it’s 14 days,” Leguen says. “This is a new condition. Anything that is said today could change tonight.”

Leguen says he doesn’t believe Southern Nevada’s status as a tourist destination renders its residents any more likely to be infected by the coronavirus.

“The tourists, they are coming from all over the world and Las Vegas is not the only city that is a tourist destination. Typically, the tourists are limited to certain areas,” he says.

A group of 195 Americans evacuated from Wuhan in January reached the end of their 14-day isolation period today and were released from March Air Reserve Base in Southern California.

“There should be no concern about novel coronavirus from these 195 individuals,” Dr. Nancy Knight of the U.S. Centers for Disease Control and Prevention told reporters, according to ABC News. “They have been watched more closely than anyone else in the United States.”

An evacuee who arrived in San Diego last week was taken with three others to a hospital Sunday where they tested negative for the coronavirus and returned to quarantine at the Miramar Air Station. On Monday, the CDC alerted California authorities that further testing revealed one person tested positive. He has since been hospitalized, according to the San Diego Tribune.