Progress vaccinating children age 12 to 15 appears to be slowing down, and though experts and officials are hopeful it will pick up, they say there is reason for some concern. As of last week, the state reported that 59,830 children in this age group had received at least one dose of the Pfizer-BioNTech vaccine, an increase of about 7,000 from the previous week. It was a relatively small increase compared to the week of May 19 to May 26 when vaccinations nearly doubled with 25,556 children aged 12 to 15 received at least one dose, the state data shows. Less than 1 percent of the population in this age group \u2014 127 children \u2014 were fully vaccinated as of last week, the state data shows. However, the Pfizer vaccine was not approved for this age group until May 10, meaning most of the children who were the first to get the shot will not be fully vaccinated until at least next week. \u201cYes, vaccination rates have leveled off very quickly among the 12- to 15-year-olds,\u201d said Peter Yazbak, spokesperson for the state Department of Education. He said turnout has varied substantially across the hundreds of student clinics that have been held in the past eight weeks. \u201cWe have seen just a handful of students get vaccinated (at some clinics),\u201d Yazbak said. \u201cOthers have vaccinated over 1,000 students in a single event.\u201d The varied turnout has a number of causes, Yazbak said, including vaccine hesitancy among parents of children in this age group. This might have been heightened last month by reports of an inflamed heart muscle \u2014 also known as myocarditis \u2014 in some young recipients of the Pfizer vaccine. The Pfizer-BioNTech vaccine is the only one approved for those under 18 years old. Moderna said it plans to ask the U.S. Food and Drug Administration for emergency authorization to administer its vaccine to children. Though it\u2019s understandable that some parents might still be hesitant about vaccinating adolescent children, the benefits outweigh the risks, said Dr. Daniel Gottschall, vice president of medical affairs for the Fairfield region of Hartford HealthCare and St. Vincent\u2019s Medical Center in Bridgeport. \u201cI certainly am sensitive to parents\u2019 concerns but, as medical professionals, we can show them that all the evidence points to this being safe for (children),\u201d Gottschall said. As numbers for children age 12 to 15 level off, health experts say there is now concern it could lead to a bump in COVID infections \u2014 and even serious illness \u2014 in this age group. A recent report for the Centers for Disease Control and Prevention showed that COVID hospitalization rates among those age 12 to 17 \u201cpeaked at 2.1 per 100,000 (people) in early January 2021, declined to 0.6 (per 100,000 people) in mid-March, and rose to 1.3 (per 100,000 people) in April. Among hospitalized adolescents, nearly one-third required intensive care unit admission, and 5 percent required invasive mechanical ventilation.\u201d No associated deaths occurred, the report stated. But overall, COVID-19 metrics have remained low in Connecticut over the past month. On Tuesday, the state recorded a daily positivity rate of 0.71 percent as 66 new cases were found statewide out of 9,356 tests. The number of Connecticut hospitalizations remained flat, with 72 patients hospitalized for the disease. Two more fatalities brought the state\u2019s official death toll to 8,255. Widespread vaccination is key to stopping the spread of the virus, said Maura Fitzgerald, spokesperson for the state Department of Public Health. \u201cAnyone, regardless of age, who remains unvaccinated is at higher risk for contracting COVID-19 and potentially suffering severe health consequences as a result,\u201d she said. \u201cVaccination is a safe, effective and powerful tool in minimizing the spread of the virus and allowing us to return to a sense of normalcy.\u201d Gottschall said there is a potential for \u201cpockets\u201d of COVID cases in adolescents, especially as more children return to camps and social activities in the summer, and to in-person classes in the fall. Even if these children do not get seriously ill, Gottschall said they can still be asymptomatic carriers of COVID, which will allow the illness to continue spreading. If vaccinations in this age group do not pick up, Gottschall said it could delay a return to normalcy and put more people at risk for the illness. For example, Gottschall said, as summer camps start to open, staff and administrators will be faced with having to make some difficult decisions. \u201cIndividual camps have to decide what makes sense for them,\u201d Gottschall said. \u201cThey have to decide whether they\u2019re going to have a masking policy or whether to limit certain activities.\u201d If camps lift restrictions, and the vaccination rate among campers is low, he said, that could increase risk of infections. As of last week, nearly 2.2 million Connecticut residents have received at least one dose of the vaccine and about 1.8 million are fully vaccinated, state data shows. \u201cThe more people that are immunized, the better off we are as a society,\u201d Gottschall said.