Massachusetts health officials this week added 11 municipalities -- including Boston -- to the red category of its coronavirus risk map, meaning they are considered at the highest risk for transmission of the virus.
The new communities bring the total number of high-risk municipalities to 23, including the state's biggest cities -- Boston, Worcester and Springfield. Those in the red have more than eight cases of COVID-19 per 100,00 people.
The designation impacts the level to which those communities can loosen restrictions imposed by the coronavirus, which had sickened 129,753 residents and killed 9,242 as of Wednesday.
Here's what you need to know.
Which Communities Have Entered the Red Zone?
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Each week, the Department of Public Health, includes a breakdown of the total number of coronavirus cases in each Massachusetts city and town, as well as the new map and more data.
The latest weekly data on the coronavirus pandemic, including the updated community-level risk assessment map, shows 23 communities considered at the highest risk for transmitting COVID-19, up eight from last week.
Among the changes is Boston moving into the red zone for the first time since the state started tracking the town-by-town data, something that Mayor Marty Walsh had been bracing for since last week.
The high-risk communities in Wednesday's report are Attleboro, Avon, Boston, Chelsea, Dracut, Everett, Framingham, Haverhill, Holliston, Lawrence, Lowell, Lynn, Lynnfield, Marlborough, Methuen, Middleton, Nantucket, New Bedford, North Andover, Revere, Springfield, Winthrop and Worcester.
Eleven communities were added to the red category since last week: Attleboro, Avon, Boston, Dracut, Haverhill, Lowell, Lynnfield, Methuen, Middleton, North Andover and Springfield.
Saugus, Tyngsborough and Wrentham dropped off the list.
The map shows the number of cases detected on average each day over the last two weeks in each of Massachusetts' communities. More than 8 cases per 100,000 translates to a high risk and red shading, between 4 and 8 cases per 100,000 is moderate risk and any less than that is low risk.
How does this impact communities?
Those communities in the red designation won't be able to move into Phase 3, Step 2 of the state's reopening process, which lower-risk municipalities will be able to do on Monday.
Gov. Charlie Baker said lower-risk communities -- those with grey, green and yellow designations on the state's weekly community-level spread map -- can move to the next step, but only if they have maintained that status for three straight weeks.
The activities allowed in Phase 3, Step 2, include indoor and outdoor recreation businesses. They "have not led to significant transmission in other states," Baker said.
Also new in the Baker administration's update are changes to gathering sizes for outdoor gatherings in public and at event venues. For Phase 3, Step 2, communities, they'll be allowed to have up to 100 people, while that limit will be 50 people for Step 1 communities when the new order takes effect.
Additionally, the Baker administration recommends remote learning for communities with a “red” designation three weeks in a row.
What does this mean for Boston?
Last week, Boston missed being categorized as high risk by just 0.1 cases per 100,000, following a warning from Walsh that the city was headed for high risk status. But this week's report put its number of cases per 100,000 residents at 8.5.
Walsh said Wednesday that Boston wouldn't be entering Step 2 of Phase 3 of the state's reopening plan on Monday since it was expected to be declared red in the report, which is released Wednesday evenings.
"Being in the red category is something we need to take extremely seriously here in Boston," Walsh said at his Wednesday coronavirus briefing. "It's not unexpected and it's based only on one data point. We've made incredible progress in the last few months and we still have the ability to continue that progress."
However, while state guidance is for communities in red to move schooling remote, Boston has been using a 4% positivity rate as its benchmark for changing course. Boston Public Schools moved to a hybrid of in-person and remote learning on Thursday and district officials didn't announce a change to that plan Wednesday night, when the recent percent positivity stood at 0.56%.
A district statement said officials "are monitoring public health guidance and we will only continue with the scheduled phase-in of the hybrid model if it is safe to do so."
A representative for the Massachusetts Department of Public Health noted Wednesday night that Boston is uniquely dense among Massachusetts' communities, with the state's largest population and a high concentration of colleges and universities and other jobs that bring people together. High levels of testing at institutions of higher education has contributed to higher numbers of positive cases as well.
How are people reacting?
Boston residents were discouraged Wednesday night to hear that the city has now moved into the "red zone," the highest risk category on Massachusetts' COVID-19 map.
The city is one of 23 communities shaded red on Wednesday's map due to having more than 8 cases per 100,000 people.
"It's unfortunate, to be honest, and disappointing," said Stephanie Sinclair, who has children who will be heading back to the school buildings in October. "Honestly taking it day by day, week by week, I can't say how I'll feel, to be honest, in a couple of weeks."
In Haverhill, Mayor James Fiorentini called an emergency meeting with the Haverhill Board of Health Thursday to discuss the rise in cases and a plan for Halloween. He plans to ask the board to require that restaurants identify customers for contact tracing and mandate masks downtown.
"We've been a totally green community up until now. All of a sudden we've seen a big jump in cases," Fiorentini said. "We've saw some of it connected with a house of worship, and some of it connected with a nursing home, and unfortunately some of those that began to spread into the community."
The city will also look at putting all school and recreational sports on hold. As for Halloween, Fiorentini said there will have to be an alternative to traditional trick-or-treating given the rising numbers.
How Massachusetts Measures Hot Spots
Massachusetts has changed over time how it's measured coronavirus metrics.
The color-coded town-by-town data was introduced in August, and the Baker administration announced that the state would focus its strongest COVID-mitigation efforts on towns in the red category. Communities can only move to Step 2 of Phase 3 of Massachusetts' reopening plan, announced Tuesday, if they are not consistently in the red.
Previously, the positive COVID test rate over the prior 14 days had been the standard for measuring hot spots. The Department of Public Health's weekly report still includes that information, along with other metrics like how many tests are being conducted locally and how many cases have been reported locally.
However, some of Massachusetts' smaller towns have taken issue with being categorized based on cases per capita.
They say that, when a town only has a few thousand people, an outbreak in just one household can send it into red, which is determined by 8 cases of COVID-19 per 100,000 residents.
Asked Tuesday why he prefers using cases per capita instead of percent positivity, Gov. Charlie Baker said Tuesday that the latter doesn't take into account that some people get tested repeatedly.
"We have a lot of repeat testers in our data, many of whom are repeating for work-related reasons," Baker said.