As of Sunday, Connecticut was ranked fourth — behind Vermont, Massachusetts and Hawaii — in the country for the percentage of the population that has received at least one dose of the COVID-19 vaccine, at 64.2%, according to data from the Centers for Disease Control and Prevention.

But vaccination rates vary widely across cities and towns in Connecticut.

Connecticut Department of Public Health preliminary data updated last Wednesday show that partial vaccination rates varied from 33.7% in Mansfield to 88.5% in Canaan. Windham County has the lowest rate by far, while in New London County — third-lowest of eight counties — rates ranged from 47.3% in Griswold to 80.2% in Lyme.

After Griswold, the next lowest rates in New London County are 48% in Sprague and 48.3% in New London.

With state grants that Gov. Ned Lamont and DPH announced a month ago, local health districts are targeting vaccination efforts to underserved communities. Jennifer Muggeo, deputy director of Ledge Light Health District, said there is "absolutely" a correlation between socioeconomic factors and vaccination rates.

She said Ledge Light is focused on New London, as well as two census tracts in Groton and one in Waterford, which score high on the CDC's "social vulnerability index."

Communities with higher SVI scores tend to have lower vaccination rates, according to an analysis CT Mirror published last week. Income, poverty level, employment status and education were most predictive of vaccination rates.

Muggeo said some barriers to vaccine access include lack of transportation, work schedules, and language, and she pushed back on the idea that vaccine hesitancy is the primary factor in lower rates.

"People have complicated lives, especially people who have been placed at risk by systems, who have to work multiple jobs, who have jobs who don't have reliable transportation," Muggeo said.

Groton resident Lizbeth Polo-Smith is a community health worker who has been working with Ledge Light on outreach to Spanish-speaking communities. She is from Peru. Polo-Smith said she has dropped off flyers at Spanish markets, churches where a lot of people speak Spanish, the New London Homeless Hospitality Center, and New London Adult & Continuing Education.

She takes pictures at vaccination clinics to show people from different backgrounds getting the shot. When there's a clinic at the OIC in New London, she walks out into the street to tell people about it.

Polo-Smith said some of the hesitancy is because some people come from countries — Guatemala, for example — where they never had vaccines as children.

Another factor for New London is that the city has an unusually young population, and young people have lower vaccination rates.

According to DPH data updated Wednesday, 53.5% of people ages 16 to 24 and 56.9% ages 25 to 34 have gotten at least one dose, compared to 90.2% of people ages 65 to 74 and 86.6% of people over 75.

U.S. Census Bureau estimates show the median age in New London for 2015-2019 as 31.6 years old — the fourth-lowest out of all 169 municipalities in the state. When looking specifically at the population over 45 that have received at least one dose, New London has a higher vaccination rate than some nearby towns that have higher rates when looking at all ages.

Ledge Light is having a harder time doing targeted outreach in New London because the census tract-level data for the city is inaccurate; each of the city's seven census tracts shows up as having a lower first-dose vaccination rate than what DPH shows as the citywide rate.

Maura Fitzgerald, a spokesperson for DPH on COVID-19 matters, said in emails Thursday that DPH is well aware of the problem but doesn't know what's causing it and therefore hasn't been able to fix it.

Muggeo said last week she had been asking about the discrepancy for weeks, and it "kind of ties our hands if we're looking at: Where in New London should we do some concentrated outreach?"

"Being where people are already gathering"

In the City of Groton, Mayor Keith Hedrick said bilingual flyers were put in everybody's door at Branford Manor, where a vaccination clinic was held. Vaccines are also being offered at mobile food pantries.

Vaccine providers are making a point of "being where people are already gathering," Muggeo said, noting that Ledge Light offered vaccinations at Eat in the Street Wednesday, the premiere of "Those People" at the Garde Arts Center on Thursday, and food pantries.

Uncas Health District is also offering vaccines at food distributions, director Patrick McCormack said. Other sites include Night Flight Basketball League games in Norwich and places where the UniteCT mobile van will be, to help eligible people apply for rental and utility assistance.

McCormack said it's helpful to go to the same location for multiple weeks. He said in the first attempt people will ask a lot of questions and say, "I just want to think about it and I'll come back." And they do come back.

Uncas Health District is partnering with UCFS, Backus Hospital, Norwich Human Services, Generations Family Health Center, and Thames Valley Council for Community Action on outreach.

Specifically, they are focused on the neighborhoods of Greeneville in Norwich, Uncasville in Montville, Jewett City in Griswold, and Baltic in Sprague.

McCormack said vaccination efforts include door-to-door canvassing, outreach to churches, and sending out flyers when sending relicensing paperwork to restaurants, to see if they'd be willing to host a clinic for staff or customers.

Like Muggeo, he pointed to transportation and language as barriers. Of course, there are also people who have no barriers to access but are simply choosing not to be vaccinated.

UCFS is working with a community health worker who is fluent in Haitian Creole and a recent Norwich Free Academy graduate who is reaching out to youth, said Yolanda Bowes, director of patient experience.

As community resource coordinator at TVCCA, Terry Dunn has been working with both Ledge Light and Uncas health districts. He said part of this involves utilizing "trusted messengers in the local community that have been here for years" to combat misinformation.

"We kind of have the staff already in place; it was just a matter of trying to coordinate a combined effort to accomplish this goal," Dunn said.

e.moser@theday.com