Officials with the CDC are tracking several new COVID-19 variants including one in North Dakota.
The new strains are descendants of the Omicron variant.
The strain EU11 is among the new variants being tracked.
Scientists first began keeping tabs on it earlier this year as it moved rapidly through parts of Europe.
It now represented 1.7% of cases nationwide, and has been identified in North and South Dakota, Colorado, Montana, Utah and Wyoming.
Virtually all Americans are now estimated to have antibodies from a vaccination, at least one infection or some combination of the two. A growing share of hospitalizations and deaths are now from reinfections according to the CDC.