Updated at 7:15 p.m.: Revised to include new Ellis County cases.

For the second day in a row, Dallas County has seen a sharp increase in positive coronavirus tests.

The county reported 100 new COVID-19 cases Wednesday, the most it has recorded in a single day. Tuesday’s total of 82 was the previous high.

Dallas County also reported two more deaths from COVID-19: a Mesquite man in his 50s and a Garland woman in her 80s. Both had been critically ill at hospitals, the county said in a news release.

There have been 731 cases of the disease in Dallas County and 15 deaths.

“We’re beginning to see the curve rise,” Dallas County Judge Clay Jenkins said in a written statement, “and we all must do our part to exercise personal responsibility.”

The county noted Tuesday that the number of intensive care unit hospitalizations related to COVID-19 in the past week surpassed the peak week of flu-related ICU hospitalizations in the 2019-20 season.

4th Dallas police officer tests positive

Meanwhile, an officer who works in the South Central Patrol Division is the fourth to test positive for the new coronavirus, according to the Dallas Police Department.

The officer has been out of the office since March 24, when symptoms began.

No one else at the station has shown signs of COVID-19, a police spokesman said.

The area of the building where the officer worked has been sanitized by a professional contractor, police said.

South Central is near Camp Wisdom and Lancaster roads in southeast Oak Cliff. The department has seven patrol divisions, and this is the third in which an officer has tested positive. The Central and Northeast patrol divisions have also reported cases.

The other officer to test positive works at the department’s In-Service Academy.

Tarrant County

Tarrant County Public Health announced Wednesday that two more people had died after testing positive for COVID-19, bringing the county’s death toll to three.

They were a man from Hurst and a woman from Fort Worth. Both had underlying health conditions, TCPH said, omitting any other information about the patients in its announcement.

The health department said it planned to investigate whom the patients may have come into contact with before testing positive.

“We express our deepest sympathy to the families,” the department said in a written statement.

These are the first coronavirus-related deaths in the county since March 15, when 77-year-old Pat James died while living at the Texas Masonic Retirement Center in Arlington.

Tarrant County also reported 15 new COVID-19 cases Wednesday, raising its total to 288. The county changed how it reports its numbers this week by including “provisional” cases.

Eighteen residents have recovered from the illness, county officials said.

Collin County

The number of COVID-19 cases in Collin County rose by 24 Wednesday.

Of the 184 total cases confirmed since officials began keeping track, 130 people were still battling the virus, officials said. One patient has died, and 53 have recovered.

The county is monitoring 211 people for signs of the virus, officials said.

Denton County

Denton County health officials reported 25 more cases of COVID-19, bringing the county’s total to 231.

None of the new patients were residents at the Denton State Supported Living Center, a facility that is home to about 450 people with intellectual and developmental disabilities and employs more than 1,400 people. Fifty residents and 23 employees at the center have tested positive for the coronavirus.

Four COVID-19 patients in Denton County have died, and 55 have recovered.

Lewisville officer tests positive

A police officer in Lewisville has tested positive for the coronavirus, Chief Kevin Deaver said.

The officer has been quarantined since March 24 after he was exposed to the virus by a relative. He was tested Tuesday, and the results came back positive Wednesday.

The department said the officer, who lives in Denton County, was in good spirits and would remain isolated.

Rockwall County

Rockwall County officials said Wednesday that a Fate resident had tested positive for COVID-19.

The county has reported 10 cases of the illness.

Ellis County

Six new coronavirus cases were reported in Ellis County on Wednesday.

There have been 25 cases in the county, including one death, and officials said to expect the number of positive tests to rise as their testing capability increases.