More than half of the United States is now under the tri-state coronavirus travel advisory.

The total stands at 31 states, with one state that was recently removed from the list, added back on.

Ten more states have been added, including Maryland, Indiana and Alaska. Delaware is back on the list, after it had been removed last week.

Gov. Phil Murphy is encouraging all individuals arriving from the hotspot states to proactively get a COVID-19 test and self-quarantine.

"I was a little surprised to see Delaware back on because people are very conscientious down there," says Barbara Wiezik, of River Vale, who is an E.R. nurse who works and lives in New Jersey, but was heading to her second home in Lewes, Delaware. "I will quarantine myself because I'm not going back to work when I come back up here. I'm going down just to check on the house, just to make sure everything is OK, stay for a couple of days and come back," Wiezik adds.

Todd Chelmowski from Indiana says he was not aware of his state being on the list, but says he will quarantine himself for 14 days.

"Yeah, I mean, if that's what they want me to do, I guess I'll have to do it," says Chelmowski.

In a statement, Murphy says: "It is critically important that all New Jerseyans remain committed to beating COVID-19 by remaining vigilant and continuing our collective efforts to reduce new cases and the rate of transmission throughout the state in order to prevent additional outbreaks across New Jersey, and continue with our responsible restart and recovery process, I strongly encourage all individuals arriving from these hotspot states to proactively get a COVID-19 test and self-quarantine."

The travel advisory recommends any person arriving in New Jersey, Connecticut or New York from one of these states to self-quarantine for 14 days.

The travel advisory applies to any person arriving from a state with a positive test rate higher than 10 per 100,000 residents or a state with a 10% or higher positivity rate over a 7-day rolling average.

Minnesota was just removed from the list, but highly traveled states like Florida and California remain.

MORE: Full list of states under New Jersey's COVID-19 travel advisory