Arrow-right Camera
Subscribe now


With delta variant, COVID-19 case rates, hospitalizations soar in Idaho

Employees schedule COVID-19 tests and prepare test kits on Nov. 24 at Primary Health Medical Group’s clinic in Boise.  (Courtesy of Otto Kitsinger)
By Ian Max Stevenson Idaho Statesman

The story of the pandemic this summer is a rapid increase in COVID-19 cases and hospitalizations across much of the U.S. that health officials say is tied to the spread of the delta variant.

In Idaho, that growth since the start of July has been multifaceted.

As recently as July 1, the state recorded 97 people hospitalized with suspected or confirmed COVID-19, and 22 people in an ICU. On July 29, there were 170 hospitalized and 56 in an ICU, according to data from the Department of Health and Welfare.

“Our coronavirus metrics have really gone the wrong way for the last several weeks,” Dave Jeppesen, director of Health and Welfare, said at a news conference Tuesday. “Perhaps most concerningly, we see an increase in the number of COVID-19 patients in the hospital and in the ICU. In fact, we’ve seen those numbers more than double since July 1.”

The number of cases across the state has quickly risen in recent weeks, too.

Idaho’s seven-day moving average of new cases fell as low as 68.3 per day on June 30. On Monday, that average was up to 358.9 per day, according to data from Health and Welfare.

The week of July 18-24, the state’s test positivity rate, which Jeppesen said is a “good indicator of virus activity,” rose to 8%, well above the 5% threshold that many health experts use to measure control of a virus.

On Tuesday, Dr. Kathryn Turner, Idaho deputy state epidemiologist, pointed to a concerning rise in case numbers among young children. The number of infected kids 4 and younger has increased about 200% in the past two weeks, Turner said. For children 5-12, case numbers have roughly doubled over the same period. Turner said the number of teenagers with COVID-19 has also “increased substantially.”

“We’ve seen increases in all of the age groups, but we’re certainly seeing a relatively larger increase in the younger population,” she said.

Jeppesen noted case numbers are expected to rise further as summer shifts into fall.

“As we look forward, we see that the fall, with the return of the flu season and people returning to more indoor activities … leaves us concerned,” he said.

Delta variant ‘widely circulating’

State officials Tuesday tied the rapid rise in cases that began last month to the delta variant, a highly contagious strain of the coronavirus.

“The precipitous increase in our daily case counts … is certainly additional evidence that the delta variant is regenerating in our communities,” Turner said.

Based on state variant surveillance data, which sequences the genomes of test samples taken from people with COVID-19 to determine the prevalence of new variants, the delta strain became dominant last month.

Dr. Christopher Ball, bureau chief of the Idaho Bureau of Laboratories, which administers the state’s surveillance sequencing, said Tuesday that 76% of sequenced samples between mid-May and mid-June were the alpha variant, a strain of the virus that was predominant around the U.S. this spring.

But over the period from mid-June to mid-July, 81.3% of sequenced samples were the delta variant.

“This rapid shift in variant composition is very consistent with what we’ve seen in other states,” Ball said. “And we can certainly say that the delta variant is widely circulating in Idaho right now.”

Part of the reason for the delta takeover, Turner said, is that it appears to be more transmissible than previous strains of the virus and might have a shorter incubation period.

People infected with previous versions of the virus spread their infection to, on average, two or three additional people, Turner said. But with the delta variant, that number is closer to five to nine people, or “at least twice as contagious.”

“Increased transmissibility poses an exponential threat,” Turner said.

And the delta variant also might be able to spread between people sooner than other versions of the virus.

“It appears that those who are infected with the delta variant tend to have more virus, and that (it) is detectable much earlier after exposure compared to infections with viral lineages that came before,” Turner said.

She noted the incubation period – the time between when a person becomes infected and is able to spread their infection to others – might be shorter, too.

“All of these factors together explain why this variant is so concerning,” she said.

Gov. Brad Little also spoke at Tuesday’s news conference, emphasizing the need for more Idahoans to get vaccinated to stem the spread of the delta variant.

“The COVID vaccine is safe and effective,” Little said. “The vaccine almost guarantees that if you get COVID, you won’t get as sick from the disease.”