Arizona's count of reported presumptive positive and confirmed coronavirus patients rose to 31 on Wednesday after new cases were confirmed in Maricopa, Pinal and Pima counties and the Navajo Nation, Coconino County announced its first case and Luke Air Force Base announced two cases.

That number is up from the 18 cases reported in the Tuesday morning update from the Arizona Department of Health Services.

The state announced it had 27 total presumptive positive and confirmed coronavirus patients in its morning report. Four other cases were reported by other entities later in the day.

Coconino County's first reported presumptive positive case is a man from the greater Flagstaff area who is over 60 years old and is isolated at home, according to a release from Coconino County Health and Human Services.

Luke Air Force Base's 56th Fighter Wing Commander announced in a Facebook post Wednesday evening that two people from the base tested positive for COVID-19. The two and their families "have been isolated in their home since first showing symptoms," the post said. Those two cases have not yet been confirmed by state or county officials.

Navajo Nation President Jonathan Nez announced Wednesday night that a third member had tested positive for COVID-19. It is a 62-year-old man from Chilchinbeto, Arizona, the same region as the first two cases. The Navajo Health Command Operations Center is now considering issuing a shelter-in-place order for Chilchinbeto requiring residents to remain in their home, according to a release from Nez.

Maricopa County identified two new cases of the disease COVID-19, caused by the new coronavirus, since Tuesday:

A woman in her 40s who is recovering in isolation at home.

A man in his 70s who is recovering in isolation at home.

Pinal County identified three new cases:

A woman in her 30s who is isolated at home and recovering.

A second woman in her 30s, with no connection to the other woman in her 30s, who is isolated at home and recovering.

A woman in her 80s who is hospitalized and is recovering in a hospital.

Details about the one new Pima County case were not immediately available.

As of Wednesday, state and county agencies had reported 11 positive cases in Maricopa County, eight in Pinal County, five in Pima County, two in Navajo County, one in Graham County and one in Coconino County.

On Tuesday, the Navajo Nation announced its first two cases in patients in their 40s who had been traveling.

The number of pending tests is 102, according to the state.

The tally of cases reported in Arizona is likely much lower than the actual number of infected people in the state because testing has been limited to people who are very ill.

Evidence shows infected people who aren't showing any symptoms can spread the virus.

The Arizona Department of Health Services this week updated its recommendations on social distancing. State health officials recommend canceling or postponing gatherings of 10 or more people and they recommend working from home when possible.

The Arizona Poison and Drug Information Center is available to answer questions about COVID-19 at 844-542-8201. Arizona providers can call for testing and patient guidance. The general public can call for information about testing, isolation and quarantine.

The Johns Hopkins University COVID-19 Resource Center was reporting 207,518 cases worldwide as of Wednesday morning, including 8,248 deaths.

Reach the reporter at Stephanie.Innes@gannett.com or at 602-444-8369. Follow her on Twitter @stephanieinnes.

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