PORTLAND, Ore. (KOIN) — New data on breakthrough cases in vaccinated Oregonians has been released by state health officials.

Oregon Health Authority reports nearly 20% of COVID-19 cases in July occurred in vaccinated people, compared to only 8% in June. However, health officials said those who were vaccinated still experienced less severe symptoms compared to those who were unvaccinated.

Of the 55 people who died of COVID in July, 91% were unvaccinated, according to OHA.

Furthermore, data shows the number of breakthrough cases in vaccinated individuals is small compared to the overall total of vaccinated individuals.

According to OHA, in Multnomah County, where 477,863 residents are fully vaccinated, only 855 breakthrough cases were reported, or about 0.179%. Clackamas County, which has 220,412 fully vaccinated residents, reported 395 breakthrough cases, while Washington County, which has 344,393 fully vaccinated residents, reported 479 breakthrough cases.

The state said all three FDA emergency-authorized vaccines work exceptionally well at preventing severe infection.

Oregon health officials have reported more than 1,000 new confirmed and presumptive cases for the past three days, and more than 2,000 cases were reported over the past weekend. More than 450 people are hospitalized with COVID-19 across the state.