The precipitous rise in COVID-19 cases, Whalen said, includes a rise in “breakthrough infections” — that is, vaccinated people getting sick with the virus. In April, breakthrough cases were very low, she said. Whalen cited rough data, which shows, of the 1,870 COVID-19 cases in Albany County between Aug. 1 and 31, eight-hundred-and-twenty-six of them were of vaccinated people. “That is a very high rate of breakthrough ...,” said Whalen. “This is a concern.”