Tuesday, April 05, 2022

CDC Nowcast: Omicron BA.2 Now Dominant Across the Nation

 

#16,672

As expected, this week's CDC Nowcast has Omicron BA.2 dominant in every region of the country, having nearly completely supplanted the original (B.1.1.529) Omicron variant, and heavily eroding the BA.1.1 variant's position. 


This week's Nowcast estimates 72.2% of all cases in the country are now due to BA.2, while just over 25% are still caused by BA.1.1.  While some areas in the middle of the country are seeing just over 50% of cases from BA.2, in the North East, they are at nearly 85%. 

Unlike what we're seeing in hard hit places like Hong Kong - with this transition to BA.2 in the United States - infections, hospitalizations, and COVID-related deaths (see charts below) all continue to fall. 


Lower infections could be due to less testing, but the other metrics (hospitalizations and deaths) would be harder to miss. 

The higher uptake of COVID vaccines, and booster shots - particularly by the elderly here in the United States - is thought to be at least partially responsible for this lower impact.  There are, however, minor differences between the BA.2 circulating in this country - and those found in Hong Kong (BA.2.2) - and that could be a factor as well. 

We may still see an uptick in cases with BA.2 - as is currently happening in the UK - and there are already several new variants on the horizon which may impact us in unpredictable ways this summer or next fall.
 
But for now, BA.2 seems to be providing the U.S. healthcare system with a badly needed respite from the worst of the pandemic.