CDC shortens recommended Covid quarantine time to 5 days, after airlines tell it to

It's widely reported today that the Centers for Disease Control is shortening the recommended isolation period for asymptotic Covid patients from 10 to 5 days.

Given what we currently know about COVID-19 and the Omicron variant, CDC is shortening the recommended time for isolation from 10 days for people with COVID-19 to 5 days, if asymptomatic, followed by 5 days of wearing a mask when around others. The change is motivated by science demonstrating that the majority of SARS-CoV-2 transmission occurs early in the course of illness, generally in the 1-2 days prior to onset of symptoms and the 2-3 days after. Therefore, people who test positive should isolate for 5 days and, if asymptomatic at that time, they may leave isolation if they can continue to mask for 5 days to minimize the risk of infecting others.

Not so widely reported today is what preceded this particular scientific decision: a decidely unscientific request from the CEO of Delta Airlines. Reuters:

Delta Air Lines Inc's (DAL.N) chief executive asked the head of the U.S. Centers for Disease Control and Prevention on Tuesday to shrink quarantine guidelines for fully vaccinated individuals who experience breakthrough COVID-19 infections, citing the impact on the carrier's workforce.

Delta's letter makes absolutely clear that they want the 10-day isolation period reduced to 5 specifically to get covid-infected workers back on the job as quickly as possible.

With the rapid spread of the Omicron variant, the 10-day isolation for those who are fully vaccinated may significantly impact our workforce and operations. Similar to healthcare, police, fire, and public transportation workforces, the Omicron surge may exacerbate shortages and create significant disruptions. Further, all airline personnel are required to mask at airports and on airplanes. Current data suggest that Omicron is 25-50% more contagious, and likely less virulent and associated with more mild disease particularly among individuals who are fully vaccinated. Further, Omicron is associated with a shorter incubation period and infectious period among the fully vaccinated. To address the potential impact of the current isolation policy safely, we propose a 5-day isolation from symptom onset for those who experience a breakthrough infection. Individuals would be able to end isolation with an appropriate testing protocol. As part of this policy change, we would be interested to partner with CDC and collect empirical data

Delta's demand was echoed by lobbyists and trade groups over Christmas ("U.S. airline industry steps up push for CDC to cut quarantine time for breakthrough Covid cases," CNBC reported).

Cynicism is a parallel pandemic of its own. All the same, the CDC did exactly what airlines demanded right after they demanded it, and I'm staying away from the airport.