1 Year, 500,000 Cases Of COVID-19 In Mass.

The state's daily coronavirus report on Monday confirmed that Massachusetts has crossed a brutal barrier, surpassing 500,000 cases of the coronavirus. The news comes exactly one year after the first case in the state was announced.

Half a million cases of the virus in a state with less than 7 million residents. And most of those cases came during the second surge, which entered with the fall season. On Sept. 22, the first day of fall, there were 126,869 confirmed cases in Massachusetts. Over the last four months, that number nearly quadrupled, with daily cases far exceeding the worst of the spring surge.

Compounding the second wave were the Thanksgiving, Christmas and New Year's holidays. While many people stayed home and did not travel for the holidays, others could not give up on the annual allure of coming together, which this year served as an opportunity for the virus to spread. Cases surged in communities in the weeks following the holidays. Some prisons also experienced outbreaks.

Gov. Charlie Baker, Boston Mayor Marty Walsh and other public leaders reimposed some restrictions on businesses and gatherings ahead of the holidays, and again after Christmas, but the measures were less stringent than those taken during the spring, and not nearly as strong as some epidemiologists and other public health experts recommended.

In the animated chart below, you can see the 20 communities with the highest average daily rate of coronavirus cases each week during the second surge. Though some communities would drop in and off the top of the list, others — like Lawrence, Revere, Saugus, Chelsea and Fall River — remained stuck with high levels of cases.

As the chart above shows, cases had been swelling steadily though October and early November, but the post-Thanksgiving and post-Christmas periods acted like a two-stage rocket, accelerating average daily cases before they began to recede by mid-January.

There have also been recent signs of progress, however. The number of cases in the fall far exceeded the spring surge, but thanks in part to developing therapies and more knowledge of how the disease works, the accompanying death wave did not reach the terrible peaks of the first onset.

Monday also saw the start of vaccinations for residents ages 75 and older. As of Jan. 28, Massachusetts had administered 496,103 doses of vaccine.

One year. Half a million cases. Half a million vaccinations.

For more on the latest data detailing the impact of the coronavirus in Massachusetts, see our statewide and town-by-town maps and charts here.