SALEM, Ore. — The Oregon Health Authority announced on Friday that has discovered the first known "breakthrough" coronavirus cases in the state — individuals who are fully vaccinated, but tested positive for COVID-19.
OHA said that there are currently four such cases. All had gotten their second dose of a vaccine at least 14 days before testing positive.
Two of the cases are in Yamhill County, and another two in Lane County. OHA said that it is working with local public health officials to investigate the origin of these cases.
Illnesses among the four cases range from asymptomatic to mild symptoms.
"Genome sequencing is underway, and we expect results next week," the agency said.
Breakthrough cases are "not unexpected," OHA said. Clinical trials of both the Pfizer and Moderna vaccine resulted in some amount of these cases, though severity of the illnesses tended to be reduced.
"Based on what is known about vaccines for other diseases and early data from clinical trials, OHA experts believe the existing vaccines are very effective," the agency concluded.
Oregon's daily number of vaccinations performed has continued to ramp up, with 25,772 doses added to the state's registry on Friday — the majority from inoculations done on Thursday. At present, a total of 649,602 first and second doses have been administered in the state, of more than 884,000 delivered to sites across Oregon.