Maryland Gov. Larry Hogan announced Thursday that all state residents 16 years and older can now pre-register online to get vaccinated at a mass vaccination site, moving up a previously announced eligibility date of April 27.

Hogan credited the new timeline with an increase in vaccine doses from the federal government available to the state.

The news comes as Maryland experiences an uptick in positive COVID-19 cases. Since Hogan lifted many of the public health restrictions on restaurants and businesses early last month, the state has seen an increase in positive COVID-19 cases. Early last month, the state’s positivity rate was at 3.36%; it has since increased to 5.3%, according to state health data. There have been 677 identified cases of new COVID-19 variants.

“We are quite literally in a race between these variants and the vaccines,” Hogan told reporters at a press conference Thursday afternoon.

Most of the variants are the B-117, also known as the United Kingdom variant, but the state health department also detected six others, including strains from New York, California, South Africa, and Brazil.

For the time being, Hogan is urging residents to continue wearing masks and practice social distancing. Hogan is also urging residents to avoid travel to New York, California, Pennsylvania, and Delaware, where these variants are prevalent. But he maintains the reopening of businesses and restaurants within the state last month had nothing to do with the spread of the variants.

“Our indication is that these variants are much more contagious that’s why they’re spreading across the country,” Hogan said.

But Montgomery County Executive Marc Elrich told WAMU/DCist that whether or not the spike is driven by a more contagious variants of COVID-19, “cases are far worse than they were on March 8.”

Andy Pekosz, a professor of microbiology and immunology at Johns Hopkins University’s Bloomberg School of Public Health, told WAMU/DCist that there are two things driving variants. The first is that variants are more efficient at infecting people, and the second is less vigilant public health behavior. “We’re seeing spring and younger populations going out and getting together more…perhaps not using as much social distancing as they should,” Pekosz says.

Pekosz says the more positive cases of COVID-19 that exist, the more likely variants can emerge, and it’s critical to cut the case rate in half over the next few weeks.

Unlike other areas of the state, Montgomery County has been more conservative in its approach to business reopening, and still requires restaurants to limit their indoor dining capacity to 50%. In part because of those decisions, the county has managed to maintain a positivity rate around 3%.

But Montgomery County Health Officer Dr. Travis Gayles warned on Wednesday that since Hogan loosened business restrictions across the state last month, there’s been a steady increase in cases across the state. “The numbers are concerning, and the numbers are increasing across the board,” Gayles said.

Elrich encouraged residents to abstain from family gatherings this Easter and Passover weekend if not everyone is vaccinated. He’s also encouraging people to continue getting tested so that variants can be detected.

Meanwhile, Pekosz says the next three to six weeks are going to be critical as more people anticipate getting vaccinated.

“What we want to do in that period of time is not just wait for the vaccine, but we want to use the public health interventions and the vaccinations to drive case numbers down,” Pekosz said. “So that when we get to a stage where most of us are vaccinated, we’ll then feel much more comfortable about going out and take advantage of the summer weather.