Idaho set some alarming coronavirus records this week.

New cases soared to a number never seen in the 20 months of the pandemic. Huge case spikes in some K-12 schools and colleges contributed to the surge.

The percentage of COVID-19 tests coming back positive also reached a peak.

Here’s a closer look at the troubling trends:

Cases: The state added 13,481 new coronavirus cases last week, shattering a record set in December 2020.

Three times last week, the state reported a daily record for new cases, including 3,266 cases on Friday alone.

As of Saturday, the state and its seven health districts reported 340,946 confirmed or probable coronavirus cases.

Case backlog: Large, and growing.

“Data for the most recent two-week period are incomplete,” the state reported on its coronavirus website. “Due to the recent surge in cases, approximately 22,000 outstanding positive laboratory results are pending local public health district review and followup.”

A week ago, the backlog was 9,900 cases.

Either way, the week’s record number of new cases is incomplete.

Child cases: Surging, as schools reopen.

For the week ending Saturday, 1,737 school-age children contracted coronavirus from Dec. 30 through Saturday — nearly 250 cases daily. From Dec. 30 through Jan. 8, the state logged about 77 child cases daily.

The weekly child cases are almost certainly a record; it’s the highest figure since October 2020, when Idaho Education News began compiling data on case numbers by age group.

Positive test rate: Clearly a record.

For the week ending Jan. 8, a whopping 25.7% of coronavirus tests came back positive.

The previous week’s rate was 17.2%.

In November 2020, during another coronavirus surge, this rate maxed out at 19.1%.

Any rate above 5% suggests a virus is out of control.

Hospitalizations: Rising, and rapidly.

On Wednesday, Idaho reported 378 COVID-19 hospitalizations, up 35% from the previous week.

Wednesday’s 98 ICU admissions are up 22%.

Despite this increase, hospitalizations remain far below record fall rates that threw the state’s hospitals into crisis standards of care.

Deaths: One slowdown.

The state reported 37 COVID-19 deaths last week, down from the preceding week. But deaths tend to lag behind a spike in cases, by several weeks.

Vaccinations: Current vaccination rates, and weekly comparisons.

• All Idahoans, ages 5 and up: 52.6%. (Last week, 52.3%.)
• 5- to 11-year-olds: 12%. (Last week: 11%.)
• 12- to 15-year-olds: 36%. (Last week: 35%.)
• 16- and 17-year-olds: 41%. (Unchanged.)
• 18- to 24-year-olds: 48% (Unchanged.)

Here are the latest booster shot rates:

• All age groups: 39.9%. (Last week, the state reported a 40.1% rate, and it’s unclear why this number decreased.)
• 12- to 15-year-olds: 5.2%, (No data available last week.)
• 16- and 17-year-olds: 14.5%. (Last week: 12.0%.)
• 18- to 24-year-olds: 15.9%. (Last week: 14.5%.)

K-12 thumbnails

The omicron surge fueled big case spikes in several of the state’s largest districts:

• Blaine County: 163 active cases last week, up from 154.
• Boise: 441 positive cases during the first week of spring semester, up from just seven the preceding week.
• Bonneville: 93 active cases Sunday, up from 66. The district closed schools Friday, and plans to reopen Tuesday.
• Coeur d’Alene: 240 positive cases, up from 74.
• Idaho Falls: 27 confirmed cases from Jan. 3 through Jan. 7, up from four between Dec. 20 and Dec. 31. No recent data available.
• Kuna: 118 positive cases Friday, up from 58 the previous week.
• Moscow: 11 new cases last week.
• Nampa: 226 cases last week, up from 92 the previous week.
• Pocatello-Chubbuck: 110 active cases last week, up from 20.
• Twin Falls: No new data available.
• West Ada: Numbers have fluctuated widely. The state’s largest district reported 383 active cases Friday, up from 149 active cases at the start of the week. On Monday, West Ada reported only 56 active cases, for a five-day window ending Sunday. 

Higher education thumbnails

• Boise State University: Cases soared to 366 during the first week of spring classes — a record for the year, and up from 179 cases the previous week. Of the new cases, 238 involved off-campus students, 70 involved residential students and 58 involved faculty and staff. Thirty students were in campus isolation beds, up from eight the previous week. The testing positivity rate remained a 17.9%, also a high for the school year.
• Brigham Young University-Idaho: 64 active cases Thursday, 57 involving students. BYU-Idaho reported a total of 50 active cases on Jan. 9. Classes resumed Wednesday.
• College of Eastern Idaho: During the first week of classes, CEI reported 26 cases, 19 involving students. CEI reported nine cases the previous week.
• College of Idaho: 40 cases in the past week. Three students are in isolation on campus, 13 students are in isolation off campus. Classes resume on Feb. 2.
• College of Southern Idaho: During the first week of classes, CSI reported 22 new cases reported, up from two the previous week. Thirteen current cases involve students.
• College of Western Idaho: Eight recent cases reported. Classes resume Tuesday.
• Idaho State University: Active cases soared to 108 for the week ending Tuesday, the second day of spring classes. This marks a peak for the school year, and a sixfold increase from the 17 active cases the previous week. Of the current cases, 74 involve students.
• Lewis-Clark State College: 17 active cases for the week ending Friday, 14 involving students; Lewis-Clark reported no active cases the preceding week. Classes resume Tuesday.
• North Idaho College: No active cases reported. Classes resumed Jan. 10.
• Northwest Nazarene University: 37 active cases reported last week, up from 28 the preceding week. In all, 69 students and employees are under stay-at-home directives.
• University of Idaho: Six reported cases for the week ending Jan. 7. No current data available.