SALEM, Ore. (AP) — The Oregon Health Authority reported 457 new confirmed COVID-19 cases on Friday, the state's largest daily total since the the start of the pandemic.

Officials attributed the rise in cases to Labor Day gatherings, the return of college students to campus and the interruption of testing during recent wildfires in Oregon.

“Today we find ourselves at another crossroads,” Oregon Health Authority Director Patrick Allen said. “After weeks of steady decline in COVID-19, cases have begun rising.”

Currently more than 32,300 people have tested positive for COVID-19 in Oregon. The death toll is 542.

For six weeks, Oregon's COVID-19 cases and rate of transmission were heading down.

However, Allen said that the most recent data provided by the Oregon Health Authority shows that the percentage of positive tests has increased from 5.6% to 6.2% and hospitalizations increased by 28%, revealing “how fragile our progress against the virus is.”

“These are discouraging numbers,” Allen said. "As experience has taught us throughout the pandemic, this is a marathon not a sprint. We cannot let the virus regain momentum. We cannot let up in our collective efforts to flatten the curve of COVID-19. ”

Dr. Dean Sidelinger, the state’s epidemiologist, gave several examples of recent outbreaks, including 35 cases connected to various university parties, Greek life parties and college sports team gatherings, and 19 cases and one death connected to a prayer and sewing group.

“These are all reminders that when we get together with friends, family and coworkers, we often let our guard down — and that is where we are seeing the spread of the disease right now,” Sidelinger said.

On Thursday, officials also reported an outbreak of COVID-19 at a seafood processing plant on Oregon's coast where 79 people tested positive.

Recent wildfires, which displaced thousands of Oregonians, have also been a factor in the increase in cases. Officials said not only did smoke and fire delay testing, it pushed people out of their homes, forcing them to spend nights at family or friends' homes or seek help at a shelter where there are hundreds of other people.

“There is significant movement of people," Allen said. "There is lots of people moving around and interacting with people.”

Many outdoor testing sites in Oregon and the state’s laboratory that processes and holds tests were closed for part of the week.

Officials said, however, that it is unclear what effects the evacuations because of recent wildfires in Oregon and the poor air quality might have on COVID-19 transmission.