MIAMI (AP) — Omicron has overtaken the delta variant in Miami-Dade County as the dominant strain of the coronavirus in a matter of weeks, according to genomic surveillance data.

Genetic sequencing of the virus showed omicron grew from a tiny fraction of hundreds of samples taken the first week of December to nearly three of every four samples taken last week.

“It is absolutely astonishing how contagious this variant has proven to be,” Miami-Dade Mayor Daniella Levine Cava told the Miami Herald. The mayor’s office provided the the genomic surveillance data.

The county contracts with NOMI Health to conduct testing, vaccination and sequencing. The company found that 76% of 504 COVID-19 samples taken Dec. 14-15 were the omicron variant. That compared to 64% of 378 samples collected Dec. 10-13, and 1.3% of the 373 samples collected Dec. 1-5, county records showed.

The variant is also sweeping the nation, accounting for 73% of new infections last week, federal health officials said.

The county is also seeing a spike in positive COVID-19 cases, which stand at 10% after dropping to about 1% a month ago, according to data.


Last week, Levine Cava reinstated an emergency order requiring hospitals to provide daily bed inventories and COVID-19 patients counts.

“And it’s on us to protect ourselves and still the most important thing we can do is vaccinate.”


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