Arizona has three additional presumptive positive cases of new coronavirus, bringing the state's total case count to nine.

The Maricopa County Health Department on Wednesday morning confirmed that one of the new cases is in Maricopa County, in a man in his 90s who is recovering in the hospital in stable condition.

The Maricopa County Department of Public Health is working to identify close contacts of the man to prevent further spread of the infection. The man's case brings the total case count in Maricopa County to three.

The other two new cases are in Pinal County. Both cases are over the age of 60 and are members of the same household of three previous presumptive positive cases. They are recovering at home, a Pinal County spokesman said.

The first patient in that household to become sick with new coronavirus is a health care worker in her 40s who is in the hospital in stable condition and is expected to be discharged this week. The woman's case signaled a change in the spread of new coronavirus in Arizona because public health officials don't know how the woman contracted the novel virus.

The woman had no known contact with anyone who was infected and had not recently traveled to any of the affected areas. Her case means that the novel coronavirus is now circulating in the community, and public health officials say Arizonans should be vigilant about handwashing and avoiding close contact with people who are sick

On Monday, Gov. Doug Ducey and Dr. Cara Christ, the Arizona Department of Health Services director, urged Arizonans over the age of 60 and people with underlying health conditions to avoid crowds, and to stock up on household supplies.

Underlying health conditions refers to people with chronic health problems, including compromised immune systems, diabetes, lung disease and heart disease. People who are older and have chronic health conditions appear to be more at risk for severe illness and complications from the novel virus.

Pima County earlier this week announced a presumptive positive case.

A total of 100 Arizonans have been tested for the new coronavirus, also called COVID-19, and 59 tests have come back negative. There are 32 pending cases, indicating there could be more positive tests in the coming days.

Health officials are focused on testing people who have traveled to affected areas; who have been exposed to an infected person; or who are severely ill and test negative for other respiratory illnesses.

There is no vaccine for the new coronavirus and no known effective treatments for it, either.

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