North Dakota health officials are hopeful that the full Food and Drug Administration approval of the Pfizer vaccine will encourage more residents to get vaccinated.

More than half of North Dakotans 12 years of age or older have received at least one dose of the COVID-19 vaccine.

At a press conference held Monday, health officials say they are seeing an increase in the number of COVID-19 cases in North Dakota, and more than half of those cases are in people under the age of 50.

Since Aug. 1, the number of active COVID cases in the state has increased threefold, from 448 to 1,508.

They also warned that the Delta variant is the predominant variant in North Dakota and say it is as contagious as chickenpox.

“We have to look at a variety of data sources to try to piece the picture together. But I think it’s clear to us that when you look at trends and when you look at what’s happening in North Dakota, these increases are real and they’re probably even underestimated from our surveillance,” said Kirby Kruger, the North Dakota Department of Health Disease Control & Forensic Pathology Section Chief.

Moderna has also applied to the FDA for full approval of its vaccine.

Johnson & Johnson says it hopes to do so later this year.