BALTIMORE (WJZ) — Philadelphia on Monday reinstated its indoor mask mandate after COVID-19 cases there increased by 50% in a two-week span.

While cases are rising once again in Maryland, it has become increasingly difficult for experts to accurately track the number of new positives with so many people using at-home test kits.

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As for whether mask mandates here could make their return, one expert tells WJZ that decision would have more to do with hospitalization rates than new infections.

Dr. Chris Thompson, associate biology professor for Loyola University Maryland, said it’s hard to interpret the data with fewer people getting tested and those who are testing at home.

“I think we’re seeing a lot of underreporting,” Dr. Thompson told WJZ.

After its positivity rate bottomed out at just below 1.5% in late March, Maryland’s positivity rate stood at 3.27% on Monday, more than double what it was.

But hospitalizations, which public health experts say is the more important metric, continue to hover around the 140 mark. The state has recorded a little more than 14,000 deaths.

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Yet with fewer people taking precautions, such as wearing masks in indoor public spaces, the professor said he fears the state could be on the verge of another increase.

Dr. Thompson said while the new variants don’t generally result in as serious of an illness, there is still a lot that we don’t know about the long-term effects of COVID-19.

“There’s a lot of new data coming out about long COVID, and that’s pretty scary,” Thompson said. “There’s some brain inflammation in a good chunk of the population.”

Based on that uncertainty and other long-term effects, such as lung issues and heart issues, he said ignoring basic safety and health protocols just is not worth the risk.

“I would really encourage people to go back to what we know works: wearing a mask, washing your hands, social distancing when you can,” he said.

With the weather getting warmer, the professor said people should look for opportunities to open windows and increase ventilation in public settings when possible.

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“And, of course, if you haven’t gotten vaccinated, get vaccinated,” he said. “Get boosted, so you’re not one of those people in the hospital.”