Omicron Is Turning Out to Be a Weak Vaccine

With each new variant, that period of protection keeps getting shorter. In the past few weeks, studies out of South Africa, the US, and China have revealed that Omicron subvariants BA.2.12.1, BA.4 and BA.5 are alarmingly good at escaping immunity from a previous Omicron infection. In practical terms, this means that for the large swath of the US population that was first infected with Covid over the winter, the post-infection honeymoon may be over. Those people might wonder how safe it is to travel, attend large gatherings and have dinner with vulnerable friends and relatives. Unfortunately, there are no easy answers. “People want it to be, ‘Am I safe or not?,’” says Abraar Karan, an epidemiologist at Stanford University. But risk is a continuum.