New Jersey now has 11 "presumptive positive" cases of novel coronavirus after new test results nearly doubled the state's count in under 24 hours.

At a press conference Monday, state officials announced five new cases — including one person who seemed to be exposed by foreign travelers who've since tested negative. Monmouth County is seeing its first two cases, after a spate of positive tests that has mostly affected North Jersey.

The cases of the virus, also known as COVID-19, are considered "presumptive positive" after being tested by the state's health lab, but not yet confirmed by the Centers for Disease Control. Officials have said they're proceeding as though all "presumptive positive" cases are confirmed.

The new cases announced Monday at the press conference, which included New Jersey Department of Health Judith Persichilli and Lt. Gov. Sheila Oliver:

• An 18-year-old from Clifton, whose symptoms first appeared Friday, March 6, and who may have first been exposed March 2. That individual has not been hospitalized. Contact tracing for that individual has just begun, but the teen had close contact with someone who has tested positive from New York. Persichilli said.
• A 48-year-old man from Berkeley Heights, with an onset of symptoms on March 1. That person has received in-patient treatment at Overlook Medical Center. That person's exposure was reported to be from symptomatic friends from Milan — but those people have tested negative, Persichilli said. "That is an unusual circumstance as it was reported to us," Persichilli said.
• A 27-year-old man from Little Silver, in Monmouth County, with an onset of symptoms on Feb. 29. That person is not hospitalized. The exposure is believed to have occurred at a conference in Boston in late February, Persichilli said. Dozens of attendees of the Biogen conference tested positive.
• An 83-year-old from Hazlet, also in Monmouth County, whose exposure to the virus hasn't yet been traced. That person was being treated at Bayshore Medical Center.
• A 30-year-old from Teaneck, whose onset of symptoms was on March 3. That person was hospitalized at Holy Name Medical Center.

The Teaneck case is the only one tested through a private lab, LabCorp. All the rest were tested by the state's own laboratory.

Prior to the cases announced Monday, officials had announced six presumptive positive results — four in Bergen County, one in Camden County and one in Hudson County.

Officials said they don't know how many cases are pending in private labs. Persichilli said the continuing spread of the virus was "concerning but not unexpected."

"It follows the trend we are seeing around the rest of the country, and the rest of the world," she said.

Though some cases haven't yet been conclusively traced, State Epidemiologist Christina Tan said there doesn't appear to be "sustained community transmission in light of what we're seeing."

Oliver urged continued "common sense" in the public response to the virus.

"If we all remain calm and informed and educated, with each passing day, and just practice common sense, the risk of an individual contracting coronavirus remains low," she said.

Dozens of potential cases remained under investigation Monday.

Also in New Jersey Monday:

• Rick Cotton, the executive director of the Port Authority of New York and New Jersey, tested positive for COVID-19, according to multiple reports. However, New Jersey officials at their press conference Monday said they don't know of any direct contact with commuters that would cause concern.

• Bergen County James J. Tedesco said his county's director of consumer affairs would be investigating reports of price-gouging. He also urged people to stop buying up bottled water, stressing the local tap water is safe. "The amount of people I've observed hoarding bottled water is unbelievable," he said.

• The state has two COVID-19 testing kits and is expecting a third, New Jersey Assistant State Health Commissioner Christopher Neuwirth said. Each can be used up to 500 times, and each has been used 216 times so far, he said. Tests are done in batches and take a few days to come back before presumptive positive cases are sent to the CDC.

• So far, New Jersey isn't putting any restrictions on businesses — but that could change, Oliver said. "Who's to say, in the days coming, if we find ourselves in a different place in New Jersey, we will revisit that conversation with businesses in NJ.

• Schools are making their own decisions about whether to close, Persichilli said. Some had closed Monday to make plans about how to handle a potential outbreak in their communities, but not because of known exposures or positive results in their communities.

• Princeton University restricted gatherings and urged students to stay home after spring break. Rowan extended its own spring break to allow school officials time for contingency planning, NJ.com reported.

• CVS said it would waive charges for home delivery of prescription medications, and Aetna would offer 90-day maintenance medication prescriptions for insured and Medicare members. It said it was working with state governments to make the same option available to Medicaid members where allowable. Aetna said it would waive early refill limits on 30-day prescription maintenance medications for all members with pharmacy benefits administered through CVS Caremark. Caremark was working with all clients to waive early refill limits on 30-day prescription maintenance medications, it said. Those announcements come after Blue Cross Blue Shield of New Jersey said last week it would cover testing for free and waive early medication refil limits on 30-day prescription maintenance medications.

Monday's announcement of more cases came as officials in some states complained they don't have enough tests to serve their populations. But the New Jersey leadership gathered Monday instead stressed prudent use of the testing kits available.

Tan said it's not practical to routinely test health care workers, or to test anyone asymptomatic — as tests of people not yet showing symptoms could give negative results if they're still in the virus' incubation period.

"Doing frequent testing might give a false sense of security," she said.

In Pennsylvania, state officials say a Montgomery County resident had been hospitalized after testing positive for COVID-19, and was in critical condition at the Hospital of the University of Pennsylvania, the Associated Press reported. Six other people in the state who'd tested positive were in home quarantines with mild symptoms.

New York Gov. Andrew Cuomo warned some New York Schools could be closed for weeks if students test positive, the New York Post reported, as the state grapples with dozens of cases in the New Rochelle area. The state has seen more than 100 positive results in all, with 19 in New York City alone. Cuomo also boasted of the state's ability to make its own inexpensive hand sanitizer through a Department of Corrections work program — which The Hill noted meant it was being made by prisoners.

Stocks slid Monday, with the price of oil sinking 20 percent at the same time the U.S. and other nations continued to grapple with coronavirus. The Dow Jones Industrial Average was down more than 2,000 points at one point.

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