Union County is the only county in the entire northeast U.S. as of Wednesday where COVID-19 transmission rates are considered low enough that masks are optional by CDC standards.

The low risk designation is based on a seven-day rolling average charted by the Centers for Disease Control.

The CDC currently designates 2,656 counties in the U.S. as high, 361 as substantial and 148 for moderate community transmission.

Union County is one of only 52 counties nationwide — and the only in-state — rated low.

Essex County was right behind, with a transmission rate considered moderate, also making masks optional, while the rest of the state was considered masks recommended, due to substantial or high transmission rates.

All of New York, Delaware, and Pennsylvania also remained at substantial or high transmission rates, as mapped by the New York Times.

“The low transmission designation is a remarkable achievement that validates all of the hard work and extra precautions we have taken since the beginning of the outbreak, including vigorous guidelines on wearing masks,” Union County Commissioner Board Chairman Alexander Mirabella said in a written release late Thursday.

“However, the data can change from one day to the next, and Union County is not an island. The fact that so few other jurisdictions have achieved the low risk status demonstrates how important it is for everyone to step up and get their COVID-19 vaccine as soon as they are eligible. Vaccination is the only sure way to reduce the risk of death and long term health impacts from this devastating virus,” he also said.

Union County was the first county in-state to set up a free mass testing site for COVID-19 in March 2020, on the campus of Kean University in Union Township. It has operated continuously since then, currently on a walk-up basis.

Once COVID-19 vaccines first gained FDA approval on an emergency basis, Union County was among the first counties to have doses available at a mass vaccination site, also at Kean University as of January.

New Jersey continues to recommend mask wearing statewide, with no actual mandate for the general population, other than on public transportation and for school staff and students, as based on CDC guidance.

For the week ending Oct. 16, the statewide COVID-19 Activity Level Report for a third straight week showed the four-county Central East region that includes Union County at high transmission.

Essex is among the four counties in the state’s North East region, which has been at moderate transmission level since late April.

As of Thursday, there were 501,169 fully vaccinated people in Essex County, according to state data, while 588,405 people received at least one dose.

In Union County, there were 362,482 fully vaccinated people, while 416,571 people had received at least one vaccine dose.

Businesses and individuals may continue such precautions as masks and social distance, despite the encouraging CDC transmission data, county officials said.

Answers to 25 common COVID-19 vaccine questions

Vaccinations for COVID-19 began being administered in the U.S. on Dec. 14, 2020. The quick rollout came a little more than a year after the virus was first identified in November 2019. The impressive speed with which vaccines were developed has also left a lot of people with a lot of questions. The questions range from the practical—how will I get vaccinated?—to the scientific—how do these vaccines even work?

Keep reading to discover answers to 25 common COVID-19 vaccine questions.

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