When a biotechnology company needed volunteers to test a new COVID-19 vaccine, a Rio Grande Valley science teacher answered the call.

Ralph Haskins, 62, volunteered to participate in the Phase 3 trial for a COVID-19 vaccine developed by Moderna, a biotechnology company headquartered in Cambridge, Massachusetts.

"Since I was a science teacher, I wanted to be part of this science experiment," Haskins said.

The Phase 3 trial started in July.

Some participants received the vaccine. Others received a placebo.

Haskins said he felt relatively safe because the vaccine had already passed Phase 1 and Phase 2 trials.

When he received the second of two shots, Haskins said he started experiencing what he described as side effects, including joint aches, a slight fever and chills.

Haskins said he feels better about going out in public because he's enrolled in the Phase 3 trial, but he still wears a mask and practices social distancing.

He'll be tested once a month for COVID-19 antibodies.

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