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caption: Ian Haydon awaits his first coronavirus vaccine injection
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Ian Haydon awaits his first coronavirus vaccine injection

Seattle man spikes fever after second dose of trial coronavirus vaccine

There’s been some excitement about the first coronavirus vaccine to be tested on humans, but a Seattle man who is part of that trial has had a reaction to a high dose of the vaccine.

“I did have some issues after getting the second dose. I had a fever and was nauseous and even fainted,” said Ian Haydon, a science communicator and vaccine volunteer.

Haydon said he recovered within a day, and that he got a dose that was 10 times more than the amount some volunteers received. Haydon also said he was happy to do his part to help determine what dose of this vaccine will be safe – if it ever becomes publicly available.

"This is exactly what a Phase 1 study is supposed to look out for," he said.

The vaccine is being developed by a Boston-based company called Moderna, which said two other volunteers also experienced full body reactions, but has not said what they were. The company has ended safety trials at the higher dose level, but testing of lower doses will continue.

This type of vaccine has never been licensed for use in humans. It uses something called messenger RNA (mRNA), which instructs your body’s cells to make a protein – a little bit of the coronavirus. The hope is that protein will trick your body into reacting and making antibodies that protect you against the real virus.

And earlier this month Moderna announced some positive news on that front: Several of the vaccine volunteers given lower doses did test positive for coronavirus antibodies, including Neal Browning of Bothel. Moderna indicated the vaccine could be ready for the public by the end of this year if all goes well.

But it’s still not clear whether the vaccine will ultimately be proven safe, or effective against the actual virus. And so far they are just at Phase I in the clinical trials. Two other stages also must be completed.