Five charts that show how Mass. is doing in the battle against the coronavirus

A vaccine dose being prepared last week at the Harvard Street Neighborhood Health Center vaccine clinic at the Prince Hall Grand Lodge in Dorchester.Craig F. Walker/Globe Staff

Coronavirus data released by the Department of Public Health continued to offer hope in the past week that the pandemic is loosening its deadly grip on Massachusetts, as the state’s vaccination campaign raced to inject shots into people’s arms to protect them from the coronavirus and its variants.

Several key indicators are showing a similar pattern. The state’s second surge this winter was followed in March by a bump that some worried might be a third surge fueled by the variants, particularly the B.1.1.7 variant that first emerged in the United Kingdom. But that bump appears to be subsiding now.

Here’s a look at some of the key data:

Cases

The seven-day average of reported cases plummeted from the height of the second surge at the beginning of 2021 to around 1,300 a day in early March. It climbed again to over 2,000 in late March and early April before dropping again. In the past week, it continued to head down, though there was a tiny uptick Wednesday.

The levels are the lowest since the peak of the second surge but they have still not dropped to the levels reached during last summer’s pandemic lull.

Hospitalizations

Hospitalizations appear to be on the decline, a trend that became clearer in the past 10 days or so. However, like cases, hospitalizations have still not yet reached the summertime lows.

Deaths

Deaths have dropped to levels reached during the lull the state saw last summer. The single-day count dropped below 10 twice in the past seven days.

Test Positivity

The percentage of coronavirus tests that come back positive dropped after the second surge, then bumped up in March before subsiding again earlier this month. The numbers continued to head down this past week, though, again, they are not as low as last summer.

The chart shows the positivity percentage with the effect of college testing programs factored out. College testing programs dilute the data because they repeatedly test large numbers of asymptomatic people in an effort to rapidly identify new cases.

Wastewater surveillance data

The amount of coronavirus found in the wastewater at the Massachusetts Water Resources Authority’s Deer Island treatment plant has been on the decline in recent weeks, hitting its lowest levels since the peak of the winter surge. Again, though — like several of the other indicators mentioned above — the levels have not dropped as low as last summer.

The results are broken down by the northern section of the MWRA system, which includes Boston, and the southern section. The northern section has dropped to lower levels than the southern.

The trends in this data are particularly intriguing because they may provide a window into what happens next. Officials and experts believe wastewater data can serve as an early warning signal of cases that will be reported days later.

Experts have said the vaccine program, which they described as a life-or-death race to protect people before variants sweep through the state, appears to be working.

More than 5.9 million shots have been administered, including more than 3.4 million first shots of the two-dose Moderna and Pfizer vaccines, more than 2.2 million second shots of those vaccines, and 205,251 shots of the single-dose Johnson & Johnson vaccine. Older people, who are more vulnerable to the deadly virus, were prioritized early in the campaign.

Dr. David Hamer, a physician at Boston Medical Center and a Boston University epidemiologist, said Thursday he was heartened by the recent trends.

“All the indicators are that there’s some decreased transmission,” he said. “The virus is not gone, but things are improving. ... If we keep moving quickly with vaccinations, it should continue to get better.”

He said it was crucial to continue to push for people who are not vaccinated to get shots, including younger adults, people who are hesitant, and 12-to-15-year-olds once a vaccine is approved for them.

“If we’re careful, in a month or two we could be in a very good place,” he said.

Dr. Howard Koh, a professor at Harvard T.H. Chan School of Public Health and a former US assistant health secretary, said Thursday, “We are turning the corner and the end of this public health marathon is in sight. But we need to keep improving vaccination numbers, outrace the variants and overcome inequities in outcomes.”

“The current COVID-19 crisis in India, where the pandemic has erupted once again after appearing well-controlled, is one global reminder that we must not declare victory too soon,” Koh, who is also a former Massachusetts public health commissioner, said in an e-mail.