One of the main reasons why Gov. Phil Murphy has ordered children to wear masks at summer camps and when school begins in the fall is because no COVID vaccine has been given emergency use authorization for kids under the age of 12.

That could soon change.

Pfizer, in partnership with the German drug maker BioNTech, has started clinical trials testing its COVID-19 vaccine on healthy children between the ages of six months and 11 years old. Part of the trial is taking place at Rutgers University.

A total of 200 Garden State kids are participating, including 100 of them between the ages of 5 and 11.

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Two additional groups of children, 50 between the ages of 2 and 5, and 50 between 6 months and 2 years are also enrolled in the trial.

Rutgers University epidemiologist Dr. Stanley H. Weiss, also a professor at the Rutgers Medical School, said kids in these three age groups will be given different amounts of vaccine.

“Typically what you would do is start with a lower dosage and check that it looks safe,” he said. “And second, you would look at the immunologic reactions to it in terms of its potential efficacy.”

He noted the number of COVID infections is much lower now than even a few months ago in New Jersey and most other areas in the United States, so not many children in the clinical trial may actually be exposed to the virus.

He said this means it will be more difficult to measure vaccine effectiveness, however we’ve learned quite a bit about how the immune system reacts to the vaccine and “the FDA has already announced that they’re willing to look at surrogate markers, which means some marker for example of the immune system to see how well you’ve reacted."

in order to determine how effective the vaccine is, “you can look at things such as antibody cellular immunity as surrogate measures of whether the vaccine works.”

He said if Pfizer gathers this type of data “and shows mounting of a vigorous immune response, that would give a guideline to us that it looks like it’s going to be effective even before we have the clinical data.”

He said when the clinical trials are completed, perhaps by the end of the summer, “I suspect they won’t have enough numbers to prove clinical efficacy but they may show evidence of a high degree of immune reactivity that looks favorable."

Weiss noted the number of participants in the clinical trial underway for younger children is much smaller than number of people who participated in the clinical trial for the adult vaccine, so there will not be nearly as much data available.

He said even if all goes well for the COVID vaccine for younger children and early use authorization is granted, we should not assume these kids will react the same way to it as adults.

“A robust follow-up of what happens in the real world is going to be essential,” he said.

Dr. Weiss noted the immune systems of younger children have not been exposed to nearly as many corona viruses as adults, so it’s very important to monitor that closely.”

NJ's most and least COVID vaccinated towns, by county

New Jersey reported just short of 4 million people fully vaccinated against COVID-19 statewide, heading into the last week of May. So how does that break down across all 21 counties?

And, how can some communities show a vaccination rate of more than 100%, according to state data? Reasons include people who have moved, those who are traveling and not residing at home where the census counted them, students who may select their school residence for vaccination data and people in long-term care (or other facility-based housing) among other reasons, as explained in a footnote on the state COVID dashboard.

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