GOV. MIKE DeWine announced that Ohio’s COVID-19 cases, which had declined to a “plateau,” are climbing again.

“During the past few weeks, we’ve seen an increase, unfortunately, in cases,” he said.

Bruce Vanderhoff, chief medical officer of the Ohio Health Department, said this is a nationwide trend.

“That mirrors much of what we are seeing in the rest of the nation. After a long and dramatic decline, cases leveled off last week and are rising this week,” he said, pointing to rising numbers in nearby Michigan, New York City and New Jersey.

Vanderhoff added that Michigan’s increases appear to be driven by more infectious mutations of the coronavirus, such as the United Kingdom variant.

He said variant cases continue to rise in Ohio as well, with the introduction of the UK and two California variants.

“These three account for more than 80 percent of our 620 genomic detections,” Vanderhoff said, adding variant cases have increased from 92 on March 12 to 173 on March 19, to this week’s 620.

“Cases … are also up in Ohio for the first week in a long time,” he said, noting the seven-day average for new daily cases this week is 1,800 compared to around 1,500 last week. “(Wednesday) we saw almost 2,500 new cases.

“This has been accompanied by a rise in our concurrent hospitalizations, up from 851 a week ago to 978 (Wednesday),” he said, adding that the seven-day rate of positive test results has increased to 4 percent from 3 percent in mid-March.

He said all parts of Ohio are impacted by increasing coronavirus cases, adding that many cases and almost half of the variant detections have been in the northern counties bordering Michigan. The zone stretches from Toledo to the Mahoning Valley.

“Ohio remains in a race against a virus that is now more contagious and it’s right back on our heels, but we can win this race as long as we don’t falter, as long as we press on with consistent masking and vaccination,” he said.

Vanderhoff also said the vaccines remain effective against the new variants.

DeWine on Thursday said 29.74 percent of the state’s population has been vaccinated.

In terms of top virus occurrence rates, Monroe County now ranks third; it had been first, due in part to its small population. Belmont County ranks seventh, Jefferson ninth and Harrison 70th.

DeWine also reported a statewide average of 167.1 positive cases out of 100,000 population. He had said all health restrictions would be lifted when Ohio’s average dropped to 50 cases out of 100,000 and remained so for two weeks.

“We were going very well for a while. Now, unfortunately, it has begun to go up,” he said. “For the past two weeks our statewide averages were just under 150 cases per 100,000. … We were headed in the right direction for a long time, but now they’ve started to go back up.”

Belmont County is no exception to this surge in coronavirus cases, with more than 70 newly infected residents this week, according to Belmont County Deputy Health Commissioner Robert Sproul. He said 5,701 cases have been confirmed in the county since the onset of the pandemic, with 330 people in isolation at home with active cases or hospitalized. Sproul said 5,264 people have recovered and 107 people have died after being infected with the virus.

Sproul added that plans are underway to meet DeWine’s goal of vaccinating as many college students as possible with the single-dose Johnson and Johnson version of the shot by May 1.