(SALT LAKE TRIBUNE) Lori Webb’s 19-year-old son died early Tuesday morning after spending nearly a month in a coma.

She said Friday she believes he died of an adverse reaction to an influenza vaccination he received on Oct. 15, the day before he first fell ill. The shot was part of a routine physical Chandler Webb got after deciding to go on a mission for The Church of Jesus Christ of Latter-day Saints.

His doctors declined to discuss his case, and public health officials emphasize the vaccine is safe, with serious side effects rarely reported.

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