SEATTLE — COVID-19 transmission in Washington is rapidly decreasing, according to the newest modeling report from the state Department of Health.
While cases, hospital admissions and deaths remain high, trends are moving in the right direction, DOH’s most recent COVID-19 modeling and surveillance report says.
However the Seattle Times reports health experts caution that much of how the next few months unfold is based on upcoming holiday gatherings and seasonal behavior changes.
The new report found that COVID-19 prevalence — the percent of residents with an active virus infection — has been declining significantly since early September. Last month, the state reported that virus prevalence was at a new high at 0.94 percent, or about 1 in every 106 people in the state. On Thursday, researchers reported prevalence around 0.41 percent, or 1 in every 244 Washingtonians.
The newest estimate reflects about a 50 percent drop in residents with an active COVID-19 infection since last month. Despite the decline, the report noted, “prevalence still remains high, similar to levels observed at the peak of the spring 2021 surge.”
Thursday’s report estimated a reproductive number — or Re, which shows how many additional people each positive person will infect — of roughly 0.83 as of early October, showing a drop from 1.14 last month, possibly brought on by increased preventive behaviors, like masking.
A reproductive number below 1 means cases could begin to decrease, though the number must stay below 1 for a “sustained period of time” to ensure a continuous drop in transmission.
“We’re hopeful that the declines we’ve seen in the last few weeks will continue, but that will only be possible if vaccination rates continue to increase and we continue wearing masks,” Dr. Scott Lindquist, state epidemiologist for communicable diseases, said in a Thursday statement.
Researchers reported population immunity in Washington has rapidly increased since August and now sits at about 63.5 percent — about 20.3 percent of immunity was derived from previous infection, while 43.2 percent came from vaccinations.
Case counts have continued to decline in the past month. As of early October, the seven-day rolling average was 2,224 infections per day — down from the most recent peak of 3,552 on Sept. 13.
