Four Oregon residents tested positive for COVID-19 after being vaccinated against the disease, Oregon health officials reported on Friday.
The Oregon Health Authority said two of the cases occurred in Lane County and two in Yamhill County.
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Two of the cases were found during routine surveillance tests. The other two appear to be connected. OHA officials did not specify which are the two.
“This is a serious development, but not surprising,” said OHA director Patrick Allen.
These reinfections, called “emergent infections”, are infections that occur more than 14 days after the administration of the second dose of the vaccine.
Given the effectiveness rate of the two vaccines – 95% for Pfizer-BioNTech and Moderna – it is inevitable that some of the 177,000 inhabitants of Oregon vaccinated will be reinfected.
It is not yet known whether these four known cases of reinfection involved a more recent variant of the coronavirus. The Oregon Health Authority is trying to obtain samples from these patients for testing, a process that could take more than a week.
The Centers for Disease Control and Prevention are collecting data on innovative COVID-19 cases, but have not yet released that data. Oregon is one of the first states to participate in its genomic surveillance program and has sent information about these cases to the CDC.
Many innovative cases were reported during the modern vaccination trials and Pfizer COVID-19. These cases tend to be asymptomatic or mild and, so far, Oregon cases fall into one of these two categories.
State epidemiologist Dr. Dean Sidelinger said it was good news, considering that the death toll from COVID-19 for unvaccinated Oregonian is almost 3,000.
“Vaccines prevent you from becoming seriously ill, even if you are not sick,” he said.
Sidelinger said that these telling cases underscore the importance of continuing to follow safety measures against the pandemic, such as wearing masks and social distance, even after receiving the vaccine. Until enough vaccines have been administered to achieve collective immunity – something that is still months away – innovative cases will continue to happen.