Thread by @opinion

The change of expert opinion was sudden.

Researchers at Harvard Medical School now say the omicron variant, not delta, is likely fueling the current surge in Covid-19 cases in the northeastern U.S. trib.al/O49sJhb

That’s cause for alarm, because researchers still don’t know much about the variant, and it’s unclear how well vaccines will protect people.

Harvard’s labs are optimized for speed but omicron is spreading faster than they can track it trib.al/O49sJhb

“I think we are in the omicron surge,” Bronwyn MacInnis, director of pathogen genomic surveillance at the Broad Institute of MIT and Harvard said.

“There’s no system on the planet that could keep up with the pace of this doubling time” trib.al/O49sJhb

In New York and New Jersey, the omicron variant made up 13% of cases as of Wednesday.

“We know it’s the most transmissible variant of SARS-CoV-2 we’ve ever seen before, and the most immune-evasive variant,” said infectious disease specialist Jake Lemieux trib.al/O49sJhb

Omicron appears to be doubling around every four days. “It’s spread around the globe in under two weeks,” Lemieux said.

“It’s likely that it will come to your holiday gathering" trib.al/O49sJhb

Total Covid-19 cases are currently surging through the Northeast corridor from Philadelphia to New York City through much of New England — an area that’s well above the national average in vaccination rates trib.al/O49sJhb

New York State just imposed new mask mandates, and New York City is making vaccines mandatory for children as young as 5 at restaurants and entertainment venues trib.al/O49sJhb

At Cornell University, in-person classes were shut down after 900 students tested positive, many with omicron.

There were no cases of severe disease, but there was concern that students might infect more vulnerable relatives during the holidays trib.al/O49sJhb

In a worst-case scenario, cases would rise so fast that even if only a small percent of infected people got seriously ill in the coming few weeks, their numbers would exceed what hospitals are equipped to handle trib.al/O49sJhb

The standard two-dose mRNA vaccines are unlikely to offer much protection against omicron infection, though they might protect against serious disease.

People who get a booster will get about 70% or 75% protection against symptomatic infection trib.al/O49sJhb

The situation in New York and the rest of the Northeast could become much worse than it has been in South Africa.

South Africa was done with its delta surge, while the Northeast is likely to experience a pandemic of delta and omicron on top of each other trib.al/O49sJhb

The good news is that a recent study of Pfizer’s antiviral drug Paxlovid found that taking the pill within 3 days of symptoms cut the risk of hospitalization by 89% for the most high-risk patients.

That drug could get FDA approval by the end of the month trib.al/O49sJhb

Between now and then there are many holiday celebrations. One Harvard researcher suggested making them safer by holding them outside and making everyone wear masks.

That might be unrealistic since it's cold out and it’s hard to socialize in a mask trib.al/O49sJhb

But pandemic fatigue might come back to bite us.

Vaccinated people should have been able to enjoy a nearly normal, low-risk summer and early fall. Now the fear is that the public’s reserve of trust and patience has been spent trib.al/O49sJhb