SACRAMENTO (KPIX 5) — The fight against COVID-19 marked a major milestone on Monday as the final trial involving an experimental vaccine began in the United States.

30,000 volunteers from 30 states plus the District of Columbia are expected to participate. Kelli from Sacramento County is one of those participants.

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“My husband is a health care worker. He deals with a lot of COVID patients and he said he’s probably going to bring it home anyway, so why not contribute to science and help find a vaccine?” remarked Kelli.

Benchmark Research in Sacramento is one of seven clinical trial sites in California. The need for test subjects is critical.

“I just pray this vaccine works. That’s what we really hope,” said Benchmark Research principal investigator, Doctor Greg Hachigian.

“Without the volunteers, we won’t know. So we are stressing for those volunteers to come and help us get this vaccine approved,” added Benchmark Lab Director Nav Kooner.

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The experimental vaccine is co-developed by Moderna of Massachusetts and the National Institutes of Health.

In the trial, half the participants get the real vaccine, the other half will get a saline solution. No one knows who gets what.

Benchmark Research is looking for 300+ volunteers 18 years of age and older from the Bay Area, Sacramento and the Central Valley.

Interested prospective volunteers can call Benchmark at 1-888-902-9605 to to see if they qualify.

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For more details about the clinical trial, visit the Coronavirus Prevention Network website or and search for trial identifier NCT04470427