SAN JUAN, Puerto Rico — Two months ago, Puerto Rico led all states and U.S. territories in Covid-19 prevention and vaccination rates among adults and children.
Now, with the rise of the omicron variant, Puerto Rico remains among the top three U.S. jurisdictions (alongside Vermont and Guam) with the highest rates of Covid-19 vaccinations, according to NBC News’ vaccination tracker.
In large part, high vaccination rates have prevented Puerto Rico's already fragile health care system from collapsing during the coronavirus pandemic so far. But it remains unclear if that will also better position the island’s 3.2 million residents to combat the omicron variant.
Since Puerto Rico's first case of the omicron variant was confirmed Monday, the U.S. territory has experienced a spike in overall Covid cases. Puerto Rico reached a positivity rate of nearly 16.5 percent on Wednesday, a rate seven times higher than it was two weeks ago, according to the local health department.
At least 926 new confirmed coronavirus cases were reported in Puerto Rico on Wednesday, adding to more than 162,000 confirmed cases that have been reported since the start of the pandemic.
But hospitalizations have remained low in Puerto Rico at a time when hospitals in almost half the states in the mainland are, on average, experiencing high stress levels, according to an NBC News analysis of data from the Department of Health and Human Services.
In Puerto Rico, 96 adults and children sick with Covid-19 are in hospital beds, in addition to seven adults who are in an intensive care unit. No Covid deaths have occurred since omicron was detected in Puerto Rico, but the virus has killed at least 3,287 people on the island since the pandemic began.
"We are being cautious with those numbers because it's still early in the increase of cases," Daniel Colón-Ramos, a professor of cellular neuroscience at Yale University and president of Puerto Rico’s Scientific Coalition advising Gov. Pedro Pierluisi on the island’s Covid response, told NBC News.
While the vaccines are very efficient at protecting people from infections, hospitalizations, and death, "their efficacy decreases with time," Colón-Ramos said. "And the first thing that gives in, is the protection against infections."
For this reason, getting a Covid-19 booster shot is "absolutely essential to protect against new infections," he added.
The case for boosters
As of Wednesday, at least 2.4 million people in Puerto Rico (79.5 percent) have been fully vaccinated, according to the local health department. But only 628,649 Puerto Ricans have gotten their Covid booster shots.
"Another way of saying that is, if you have the two doses of the vaccine and you haven't boosted, then your protection against an infection by omicron is less because omicron has dozens of mutations in the protein that is normally recognized by the antibodies that emerge from the vaccine," Colón-Ramos said. "It's the same reason why the omicron escapes the monoclonal treatments. ... It's like a wolf dressed as a sheep. The virus has a costume now and it’s harder for the antibodies to identify it."
Because of this, Puerto Rico has become one of the first jurisdictions alongside California and New Mexico to require health care workers to get booster shots. In Puerto Rico's case, they're also requiring teachers and other school personnel to get the booster by Jan. 15.
Pierluisi has issued a series of executive orders to combat the rise of the omicron variant during the holiday season.
Travelers coming to Puerto Rico on domestic flights must bring a negative Covid test processed at least 48 hours before arrival, regardless of their vaccination status.
People attending mass-attendance events must be fully vaccinated and present a negative Covid test performed 48 hours or less before attending the event. This will also be required for those attending events that "promote the agglomeration of people" — including theaters, amphitheaters, stadiums, coliseums and convention centers, among other venues.
Starting Monday, only people who are fully vaccinated will be allowed inside food and beverage establishments.
Puerto Rico was poised to host the first Spanish-language countdown for ABC's “Dick Clark’s New Year’s Rockin’ Eve With Ryan Seacrest."
But Pierluisi announced Wednesday that the event will take place virtually "so that everyone in Puerto Rico and the rest of the world can enjoy it safely."
"This judicious and reasonable decision will not affect the participation of artists, nor the television broadcast set to reach more than 18 million viewers nationwide and worldwide. 'The Dick Clark's New Year's Rockin' Eve' event will still air on ABC, while 'De Puerto Rico Para el Mundo' will air on Telemundo Puerto Rico," Pierluisi said in a statement in Spanish.
Experts like Colón-Ramos are encouraging people to limit, cancel or postpone any Christmas gatherings and parties beyond immediate family members "during this uncertain period of Omicron's rebound. It is up to all of us to collaborate," he tweeted on Wednesday.
"There are people right now who are healthy and making plans for Christmas, and maybe wearing ugly sweaters, maybe planning their next ski trip — that in two or three weeks might be in a hospital or worse," Colón-Ramos said. "It's totally avoidable. That's what I lose sleep over."