December 29, 2021 – The CDC added to research advising the Omicron variant can lead to reinfections that are characterized by mild COVID-19 symptoms. A cluster of recent COVID-19 cases in a family of six in Nebraska indicated that Omicron is able to infect people who have had past infections, and it causes milder symptoms in some people with immunity, according to the CDC. Reports in The Wall Street Journal said the variant also seems to bring about earlier symptoms – in about three days following exposure, rather than five days or later.