MANILA, Philippines (Update 2: January 5, 1:51 p.m.) — The XBB.1.5 subvariant, a new version of the Omicron variant, is taking over the United States, raising concerns about a potential surge in COVID-19 cases.
Estimates from the US Centers for Disease Control and Prevention last week showed that XBB.1.5 is responsible for around 40% of the confirmed cases there, up from 20% a week ago. About 75% of cases in the Northeast—or regions spanning New Jersey through New England—are caused by the new variant.
Related Stories
In the Philippines, the presence of the XBB.1.5 subvariant has yet to be detected.
Here’s what we know and don’t know about the new COVID-19 subvariant.
What is XBB.1.5?
Maria Van Kerkhove, COVID-19 technical lead of the World Health Organization, on Thursday said that XBB.1.5 is "the most transmissible subvariant that has been detected yet."
The Omicron subvariant has been detected in 29 countries so far.
XBB.1.5 is a spinoff of the Omicron XBB subvariant, which is a recombinant of the Omicron BA.2.10.1 and BA.2.75 subvariants.
The XBB subvariant drove the surges of infections in Singapore and India in October. Health authorities in the Philippines have so far detected 878 cases of the XBB subvariant.
What makes it different from XBB?
Andrew Pekosz, a virologist at Johns Hopkins University, told CNBC that XBB.1.5 is different from XBB because it has an additional mutation that makes it attach better to cells.
Are experts worried?
Some medical experts are increasingly worried about the XBB.1.5 and the XBB subvariants.
Van Kerkhove said the WHO is "concerned about its growth advantage." She explained that XBB.1.5 has mutations that allows it to attach to cells better and replicate easily.
Yunlong Cao, a genomics researcher and assistant professor at China’s Peking University, said on Twitter last week that XBB.1.5 evades protective antibodies as effectively as the highly immune evasive XBB.1 variant.
The superior growth advantage of XBB.1.5 has been well-documented by many colleagues @JPWeiland @LongDesertTrain @EricTopol. Here I'll add some experimental data:
— Yunlong Richard Cao (@yunlong_cao) December 28, 2022
1) XBB.1.5 is equally immune evasive as XBB.1, but
2) XBB.1.5 has a much higher hACE2 binding affinity. 1/ pic.twitter.com/jsk7gcyfu4
Dr. Michael Osterholm, an infectious disease expert at the University of Minnesota, told Reuters that "probably the worst variant that the world is facing right now is actually XBB."
In a series of alarming posts on Twitter, epidemiologist Eric Feigl-Ding called the XBB.1.5 a "super variant" and warned that it is "one of the most evasive variants against immunity."
????Global spread in just days—Let’s be clear—the #XBB15 super variant is a US-origin variant from Northeast US. The @CDCgov is cowardly in refusing to admit it.
— Eric Feigl-Ding (@DrEricDing) January 3, 2023
????Watch the incredibly fast spread (animation by @Mike_Honey_). @CDCDirector needs to wake up. pic.twitter.com/QFRYYe2yJI
Does XBB.1.5 cause more severe illness?
According to Van Kerkhove, there is no indication yet that XBB.1.5 causes more severe illness than other types of COVID-19.
Dr. Barbara Mahon, director of CDC’s Coronavirus and Other Respiratory Viruses Division, also said that areas with many cases of the variant have not experienced a disproportionate rise in hospitalizations.
“We’re seeing hospitalizations have been notching up overall across the country… They don’t appear to be notching up more in the areas that have more XBB.1.5,” she told NBC News.
There's a lot of doom-centric chatter about the latest Covid variant, #XBB15. Here in New York City, the Covid metrics are looking pretty decent: https://t.co/jx29WpUra7 pic.twitter.com/gId6z0FZ96
— Benjamin Ryan (@benryanwriter) January 2, 2023
What should Filipinos do?
The Department of Health said the government continues to implement surveillance and monitoring activities, and is confident in detecting variants that may enter the country.
"COVID-19 variants will continue to emerge and re-emerge," the DOH said.
"What's important is we continue to employ our layers of protection such as sanitation, masking, distancing, vaccination and boosters, as well as good ventilation to keep cases manageable and prevent virus transmission," it added.