Moderna said on Thursday a third shot of its two-dose vaccine for the Chinese coronavirus will “likely be necessary” prior to winter — news that follows discussions of ongoing coronavirus booster shots similar to an annual flu shot.

Moderna announced additional data on its vaccine on Thursday, revealing it is maintaining a 93 percent efficacy six months after the last dose of the shot.

“We are pleased that our COVID-19 vaccine is showing durable efficacy of 93 percent through six months, but recognize that the Delta variant is a significant new threat so we must remain vigilant,” Moderna CEO Stephane Bancel said in a statement.