This virus infects millions—and we just discovered its secret weapon

Scientists have discovered a stealthy mechanism that cytomegalovirus (CMV)—the leading infectious cause of birth defects in the U.S.—uses to infiltrate blood vessel cells while evading immune detection. The virus forms a hidden protein complex that acts like a molecular “backdoor,” allowing it to bypass the immune system’s defenses. This newly identified pathway may explain why vaccine efforts have failed for decades and opens the door to targeted therapies that could finally prevent CMV-linked birth defects in newborns and protect vulnerable patients.