Delta variant wasn’t detected in Alaska until a few weeks ago. Now it’s 40% of samples.

a person pipettes something into a tray
A researcher at a University of Alaska Anchorage lab prepares samples for sequencing — the process that scientists use to detect specific strains of the virus that causes COVID-19. (Jeff Chen/Alaska Public Media)

Alaska’s viral detectives have recorded a sharp increase in the number of cases of the more-contagious delta variant of the virus that causes COVID-19. The strain jumped from 7% to 40% of samples in just two weeks, according to a report published this week.

“We’re looking at a really fast-moving, infectious virus,” said Jayme Parker, who heads Alaska’s public health labs.

The numbers recorded by the researchers conducting viral sequencing — the complicated and labor-intensive process of detecting variants — don’t provide a perfect picture of how delta is spreading across the state. Some regions have higher levels of sequencing than others.

RELATED: Scientists team up to make Alaska a leader in the hunt for new COVID-19 strains

But officials say the delta variant’s fast-growing share of the samples analyzed in Alaska tracks with what’s happening across the country, as the substantially more contagious strain crowds out others.

The delta variant made up an estimated 3% of cases in the U.S. in mid-May, according to the Centers for Disease Control and Prevention. A month later, it represented 30%.

State officials say that the variant threatens to boost the number of cases in Alaska, which have been ticking up from recent lows for the past three weeks. It could put new stresses on the state’s health care infrastructure.

But officials also underscore that existing vaccines still appear to be highly effective against the strain — which, they say, provides another argument for getting the shots.

A woman smiles at the camera
Alaska Chief Medical Officer Dr. Anne Zink (Jeff Chen/Alaska Public Media)

“While every choice we make has risks and benefits associated with them, for the vast majority of people, getting vaccinated is a much safer choice for preventing illness and minimizing the impacts of this virus on your life,” Dr. Anne Zink, Alaska’s chief medical officer, told reporters at a briefing Thursday. “I just continue to encourage Alaskans to seriously consider that option, particularly as we see the delta variant spreading.”

[Sign up for Alaska Public Media’s daily newsletter to get our top stories delivered to your inbox.]

The delta variant was first identified last year in India, and is now present in all 50 states. Research suggests it’s 50% more contagious than the alpha variant, which itself was 50% more contagious than the original strain of the virus first seen in China. Preliminary research also suggests the delta variant can cause more severe illness, though those findings are not conclusive.

The strain was first detected in Alaska in late May, in the greater Anchorage area. But cases have now been discovered in many other parts of the state, according to the sequencing report published this week by state and university researchers.

This chart, produced by Alaska researchers, shows how the delta variant of the virus that causes COVID-19, has quickly increased in prevalence. (Alaska Sequencing Consortium)

That report shows just how quickly the variant took hold in Alaska: In the week of May 23, researchers found zero cases of the delta variant through their sequencing work. The next week, delta represented 7% of cases — then 16% the following week, and 40% the week of June 13, the latest available data. (There’s typically a lag in getting sequencing data because it takes researchers time to access and process samples.)

Officials aren’t downplaying the risk posed by the delta variant. But they say it doesn’t change the underlying strategies they’re using to fight the COVID-19 pandemic — from treating individuals to community-wide recommendations to slow transmission.

“In terms of prevention, the same strategies apply,” Dr. Joe McLaughlin, the state epidemiologist, said at Thursday’s briefing. “It’s more like an escalation.”

Nathaniel Herz is an Anchorage-based journalist. He's been a reporter in Alaska for a decade, and is currently reporting for Alaska Public Media. Find more of his work by subscribing to his newsletter, Northern Journal, at Reach him at

Previous articleLISTEN: How did this Anchorage runner go missing in a popular mountain race?
Next articleEnvironmental regulators to give Alaska LNG pipeline another look