Massachusetts health officials on Tuesday reported ... 290 more deaths in people with breakthrough cases. In the last week, 27,530 new breakthrough cases - infections in people who have been vaccinated - were reported, with 555 more vaccinated people hospitalized over the period. It's a 40% drop in the rate of new breakthrough cases in Massachusetts - the previous week saw 46,092 new COVID infections in vaccinated people. On Tuesday ... there were 127 new deaths reported -- a statistic that includes three days because of the weekend -- bringing the death toll to 21,546. The seven-day average test positivity stands at 7.13%. In December, Massachusetts Department of Public Health officials released a study that found that 97% of breakthrough cases in the state did not become severely ill and rarely led to deaths, especially among young people. Massachusetts' COVID metrics, tracked on the Department of Public Health's interactive coronavirus dashboard, have been trending downward after spiking to heights not seen since previous surges, a peak thought to be driven at least in part by the omicron variant.