PORTLAND, Ore. — A new and highly transmissible COVID-19 strain called XBB.1.5 is making its way across the United States, setting off a fresh wave of infections.
Health officials don't yet have clinical data to know exactly how much protection the existing booster vaccines provide against XBB.1.5, according to Dr. Katie Shariff with Kaiser Permanente, but there is evidence that being vaccinated will help people avoid severe symptoms.
"We do have good clinical data to suggest that a prior vaccination series with the original strain and the boosters appears to provide long standing protection against severe disease and hospitalization," she said.
The current "bivalent" booster series in use in the United States is designed to target both the original SARS-CoV-2 coronavirus and the BA.5 strain of the omicron variant, which was the dominant strain for much of last year.
The original omicron variant began spreading in late 2021 and quickly crowded out all prior variants due to its much higher transmissibility. Every new COVID version that has become dominant since then has been a strain of omicron, including XBB.1.5, according to the World Health Organization.
The symptoms of the new variant include coughing, fever and muscle aches, much like the flu. Sharff said the new strain is very contagious and spreading quickly, already accounting for almost 28 percent of cases nationally.
RSV and flu cases have begun to decline after surges in late 2022, but health officials are starting to see a rise in COVID-19 cases at the same time, she said.
"Individuals who are 65 and older, multiple medical conditions, pregnant women, those are individuals we should really be messaging that need their booster," Sharff said.
At LECARE Pharmacy in Northeast Portland, pharmacist Thanh Lee said staff have given out almost 25,000 vaccines since the summer, and the pace is picking up in recent weeks as the new strain spreads.
"We've been seeing a lot of young people coming in to get the vaccine," Lee said.
At Virginia Garcia Clinic in Hillsboro, Director of Patient Support and Safety Hazel Wheeler said staff have been seeing an increased number of patients with the virus. He said most of the patients they serve are Hispanic, and the positivity rates are over 20%.
"We have larger family structures closer together, and folks are unable to call in sick so they don't have the ability to call into work or self quarantine," Wheeler said.