HealthDay News — Surveillance and characteristics of the SARS-CoV-2 omicron variant are described in a report published in the December 10 early-release issue of the US Centers for Disease Control and Prevention Morbidity and Mortality Weekly Report.

Researchers from the CDC COVID-19 Response Team summarized US surveillance for SARS-CoV-2 variants, characteristics of the initial persons with COVID-19 attributed to the omicron variant, and public health measures instituted to slow the spread of omicron.

The researchers note that enhanced surveillance was initiated through the National SARS-CoV-2 Strain Surveillance on November 28, 2021, to accelerate detection of COVID-19 cases attributed to the omicron variant. The first US case was identified on December 1, 2021, and 22 states had reported cases as of December 8, 2021. The earliest date of symptom onset was November 15, 2021. Of the first 43 cases of COVID-19 attributed to the omicron variant, 58% were in persons aged 18 to 39 years. One-third (14 persons) reported international travel during the 14 days preceding symptom onset or positive test results. Seventy-nine percent of the COVID-19 cases attributed to the omicron variant occurred in persons who had completed the primary series of a US Food and Drug Administration-authorized or approved COVID-19 vaccine 14 days or more prior to symptom onset or positive test result; 14 had received an additional or booster dose, including 5 who received the additional or booster dose less than 14 days before symptom onset. Six persons had a documented previous SARS-CoV-2 infection. Cough, fatigue, and congestion or runny nose were the most commonly reported symptoms. One vaccinated patient was hospitalized for two days; to date, no deaths have been reported.

“The rapid emergence and worldwide detection of the SARS-CoV-2 omicron variant underscores the importance of robust genomic surveillance systems and prompt information-sharing among global public health partners,” the authors write.

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