Pfizer board member and former Food and Drug Administration head Scott Gottlieb said federal health officials’ messaging on COVID-19 booster doses is generally unclear. The “confusing messaging” from the Centers for Disease Control and Prevention (CDC) regarding COVID-19 booster shots “may end up being one of the biggest missed opportunities in this pandemic,” Gottlieb told CBS on Sunday. “We now see very clear evidence of declining vaccine effectiveness over time. There’s different reasons why that may be the case, but the trend is unmistakable. And this has been apparent since the end of the summer, now it’s very clear,” Gottlieb added, arguing that Americans who are eligible should get a booster. Gottlieb, like other current and former health officials, has not publicly elaborated on a timeline for vaccine booster doses. Some countries like Israel have required booster shots six months after the second vaccine dose in order for a person to …