By CBS3 Staff

TRENTON, N.J. (CBS/CNN) — New Jersey Gov. Phil Murphy says the state is working to prevent double-booked vaccine appointments. A system glitch with the state’s online vaccine scheduling system caused trouble at the Gloucester County vaccine mega-site yesterday.

“Unfortunately, we needed to cancel a number of appointments that were erroneously double-booked. We will work with those canceled on rescheduling their appointments at the nearest available time. We regret the confusion this technical issue caused and we are working with our vendor,” Murphy said.

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In a statement, the director of the Gloucester County Commissioners says the trouble began when they had to switch to a backup scheduling system because the state’s system went down.

Meanwhile, New Jersey-based Johnson & Johnson’s COVID-19 single-shot vaccine was shown to be 66% effective in preventing moderate and severe disease in a global Phase 3 trial, but 85% efficacy against severe disease, the company announced.

The vaccines already on the market in the U.S. are about 95% effective overall against symptomatic COVID-19, with perhaps even higher efficacy against severe cases.

But experts say the Johnson & Johnson vaccine will still be useful against the pandemic in the United States and around the world.

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