Here is what you’ll want to learn about COVID’s XBB.1.5 “Kraken” variant

The family tree of omicron variants has grown considerably in the last year. The brood now contains a subvariant soup with alphanumeric names such as BA.2, BA.5, and BF.7. The U.S. Centers for Disease Control and Prevention estimates that two versions — BQ.1 and BQ.1.1 — caused more than half of new infections in the U.S. during the week ending Jan. 7.

Now, a newcomer dubbed XBB.1.5 appears to be gaining momentum. It accounts for more than 80% of new cases in parts of the northeastern United States, the CDC estimates. It was responsible for 43% of new cases nationwide in the week ended Jan. 14.

However, while previous variants such as alpha, delta and Original Omicron Associated with a large surge in new infections, it is unclear whether XBB.1.5 is destined to follow a similar path (Serial Number: 12/21/21). Preliminary evidence suggests that the subvariant nicknamed Kraken in some circles is more contagious than its predecessors.However, this trait is A hallmark of viral evolution — Successful new variants must be able to outperform their siblings (Serial Number: 5/26/20).

Currently, experts from the World Health Organization are paying close attention to XBB.1.5.but it is too soon Will it take over the globe. Most of the current cases are from the US, UK and Denmark.

science news Chat with UCSF infectious disease expert Peter Chin-Hong about the latest coronavirus variant making headlines. Dialogue has been edited for length and clarity.

serial number: What is the difference between XBB.1.5 and earlier versions of omicron?

Jinhong: There are many variants in production all the time. This is a normal thing for viruses, as viruses make more copies of themselves. It’s not exactly precise or exact, so it will be wrong, [which are the variants]. It’s a bit like a broken copier in the office.

XBB is the sibling of XBB.1.5, and it’s scary — and this is coming in the fall of 2022 — because it’s one of the most immune-evading variants around. But the reason XBB never caught on around the world — it was, in fact, in Singapore and India — is because it doesn’t actually infect cells.

XBB.1.5 has the immune slipperiness of XBB, but it also has this new mutation that easily infects cells. So it’s kind of like a pit bull not wanting to let go of the cell.And the XBB is kind of invisible, like it has an invisibility cloak harry potter, it does not snap. But the XBB.1.5 has the invisibility cloak, and the bite.

serial number: Is that why it spread so effectively in some areas?

Jinhong: We think so. Because if you’re a virus, being able to infect cells very efficiently is a really important superpower.

you can be invisible [to the immune system] All you could want, but if you can’t efficiently infect cells, you probably won’t be infectious.that might be [the reason] XBB.1.5 is spreading because it has both of these advantages. Now seeing how it crowds out other variants makes us worry that it’s something to watch out for. Accompanied by an increase in the number of cases and hospitalizations.

serial number: A previous variant has been linked to a surge in infections. Can we expect the same for XBB.1.5?

Jinhong: it’s complicated. If it was March 2020, it would be a very simple answer: yes. But in January 2023, people are experiencing COVID very differently, even if it’s a different type.

You can infect someone two or three times, and they’re vaccinated and boosted. That would be a really, really good person who wouldn’t get seriously ill. Maybe they have a cold. Maybe they don’t even know they have the virus, and those who are not vaccinated, have never been exposed to the virus and are older. For them, it might as well be March 2020.

That [second] For example, there are such people in China. In China, XBB.1.5 may cause many problems. But XBB.1.5 go, you know, mid-Manhattan probably won’t cause as many problems in a highly vaccinated and exposed population.

[Timing also matters] Because we’ve seen a lot of BQ.1, BQ.1.1 recently, a lot of people got infected after Thanksgiving. The rise of XBB.1.5 comes after many people have been infected recently. So it probably doesn’t do that much damage as if you had a long lull and all of a sudden you have this new thing.

serial number: Are vaccines and treatments still effective?

Jinhong: The newly upgraded booster is usually a little better than the old vaccine in terms of overall efficacy and protection against infection. But with new variants like XBB.1.5… if you want to prevent infection, even a mild infection, the vaccine might last three months.

But if you’re talking about preventing me from dying or going to the hospital, these vaccines will give me increased protection for many, many months, probably until next winter for most people. For seniors over 65, if they’re not getting strengthened today, that’s a problem.

[Drugs such as] Paxlovid and remdesivir act independently of the spike protein [the part of the virus targeted by vaccines but where many of the defense-evading mutations are (SN: 3/1/22)]. So it doesn’t matter what invisibility cloak the variant has. They will get to work as they work to shut down the virus factory, one of the early steps before making the spike protein.

So they will work anyway [spike] Variants appear, and that’s a good thing. Even if you are not vaccinated or have never been exposed to the virus, if you are diagnosed and treated early, your hospitalization rate will be greatly reduced.

Right now, none of the monoclonal antibodies work. [The virus has changed too much (SN: 10/17/22).]

serial number: Why only the omicron variant pops up?

Jinhong: I think omicron found a magic formula. It’s hard to kick it off the gold medal table. It’s very good at spreading, and all the other things that are good for a virus.

inside [earlier] A few days, two or three months later, you find a new variant of the coronavirus somewhere in the world. It’s been omicron since two thanksgivings ago.

serial number: Since each variant spreads more easily than the last, is it inevitable that everyone will get COVID?

Jinhong: People who have not been infected before will have a hard time escaping this infection. But it’s not impossible. It’s only going to get harder, not only because XBB.1.5 is so widespread, but because we don’t have as many restrictions anymore. You’re going to the grocery store and no one is wearing a mask, or you feel like you don’t have peer pressure to wear a mask. So you’ll be exposed like a cold….

However, if you have not been vaccinated, you can reduce your short-term risk by getting vaccinated.certainly [the booster] May reduce risk of death, especially if you are older or immunocompromised…

[People still wearing masks] A very good quality mask must be worn [such as KN95s] Because you can no longer rely on everyone else wearing a mask.

serial number: How worried should people be about XBB.1.5?

Jinhong: The world is divided into two types of people. Those who are physically very, very experienced with COVID — have had a vaccine or a booster or … several infections. And there are people whose bodies don’t have a good experience with COVID.for that reason [latter] group, they should be worried.

For someone, you look around and your neighbor got it and nothing happened, or your cousin or the staff, it doesn’t seem like a big deal.But 500 people are still dying in the U.S. every day [from COVID]. For those people, this is a big deal….

It’s an odd situation because it’s no longer one size fits all, and different people have different levels of risk.