Oregon recorded 575 cases of COVID-19 Thursday, the highest number since the start of the pandemic in March, according to the Oregon Health Authority.

Washington County alone reported 107 new cases. Multnomah County reported 102. 

“Preliminary data show this increase reflects continued widespread community transmission resulting in small clusters and outbreaks statewide,” the OHA said in its daily update.

Some of the cases are coming from gatherings of friends, coworkers, household contacts, travel and workplace exposure, said Deschutes County Health Department spokesperson Morgan Emerson. And as temperatures cool, people are spending more time indoors.

“This can increase risk if you are spending time with people you don’t live with,” Emerson said. “You should wear a mask and distance any time you’re around people you don’t live with and socialize outdoors if possible.”

The record number of positive test results is prompting health authorities to ask parents to not let their kids trick-or-treat on Halloween this Saturday and to avoid costume parties with people outside their household.

Officials also urge residents to wear a face covering indoors when coming in contact with people outside their household.

On Thursday, the Oregon Health Authority reported two more COVID-19 deaths, bringing the total number of deaths to 673 in Oregon. The two most recent deaths were women in their 90s, from Multnomah and Marion counties. One died Wednesday at Legacy Mt. Hood Medical Center and the other died Tuesday at her home.

At the same time, the number of newly tested Oregonians rose to 31,448 and the percentage of positive tests held steady at 6.5%, according to the health authority. 

Nationwide, the number of cases rose 78,981 and 994 new deaths were reported on Thursday, according to Johns Hopkins University of Medicine coronavirus information. Cases are rising in more than 45 states, according to data from Johns Hopkins.