Particularly in West, COVID-19 summer wave intensifies with new variety LB.1 on increase

According to federal data, a summertime wave of COVID-19 infections is spreading sooner than it did in a larger portion of the nation. This is likely due to the possibility that a new strain of the virus known as LB.1 will emerge as the most recent dominant strain.

According to CDC estimates, COVID-19 infections slowed this past week in all states and territories for the first time in months. Indicators of the key virus seem to be becoming worse at the fastest rate in some western states, where trends started to pick up this month.

The amount of viruses found in western wastewater is getting close to what the Centers for Disease Control and Prevention considers to be “high” levels of infection risk. These viruses are frequently an early indicator of increased COVID-19 infections. COVID-19 instances from nursing homes had increased recently from this area as well.

COVID-19 patients accounted for 1.23% of ER visits on average in HHS Region 9, which includes the states of Arizona, Hawaii, and West Virginia. Since early February, this is the worst average of COVID-19 ER visits in the area.

Authorities have been monitoring spikes in COVID-19 cases following a springtime dip since the beginning of the pandemic, albeit at varying intervals over the warmer months.

The nationwide increase from the previous year did not start to pick up until late July. At the end of August and the beginning of September, trends of the virus in emergency rooms peaked, coinciding with preparations for the introduction of a new COVID-19 vaccine shot by government authorities.

We have years and years of data for both RSV and flu, and the trends over time are remarkably similar. Therefore, although you can’t precisely set your watch by the start of certain seasons, you can come close. Ruth Link-Gelles, the chief of the CDC’s COVID-19 vaccine effectiveness project, stated this month at a Food and Drug Administration meeting that “that’s not true at all for COVID.”

The emergence of KP.3 and LB.1 variations

COVID-19At the same time that 19 new cases are emerging, the CDC reports that it is monitoring two novel variations that are spreading across the country. Scientists refer to them as LB.1 and KP.3.

As per the CDC’s “Nowcast” forecasts released on Friday, KP.3 has reached around a third of cases countrywide, up from 25% two weeks ago, and LB.1 accounts for 17.5% of cases.

Both are replacing a near relative known as KP.2, a so-called “FLiRT” variety that had become dominant a month prior. According to the CDC’s current forecasts, LB.1 is expected to begin growing more quickly than KP.3, indicating that LB.1 may surpass KP.3.

The JN.1 strain that caused a wave of cases last winter is the common progenitor of all three of these variations.
“KP.2, KP.3, and LB.1 are descendants of that that we have observed progressing. Thus, these additional novel variations appeared really rapidly. Though they happened quite rapidly, we had to respond, so I wouldn’t say they took us off guard,” Dr. Peter Marks of the FDA stated on Friday.

Marks was defending the agency’s decision to select KP.2 as the strain for Moderna and Pfizer’s revised injections this autumn during a webinar organized by the organization Champions for Vaccine Education, Equity, and Progress this month.

That overturned the previous recommendation by a group of independent experts to the FDA to suggest injections for JN.1. There was a lot more information available when the panel was choosing between the two variations for the fall shot, JN.1.

Although Marks acknowledged that the decision to switch to KP.2 was not supported by “iron-clad evidence,” officials believe it will provide at least a slight improvement over shots intended for the previous variant.

“There’s probably some degree of cross-protection, but the optimal protection probably involves making sure we get closest to what is actually circulating now,” he stated.

Following the FDA conference, the CDC started monitoring KP.3 and LB.1’s ascent to surpass KP.2.
While the CDC has tracked for some previous novel varieties, it is unclear if it has noticed any changes in the severity of KP.3 or LB.1. An inquiry for comment was not immediately answered by an agency representative.

This month, preprint data from Japanese scientists that have not yet undergone peer review were made public. They discovered that one of LB.1’s mutations, S:S31del, which is absent from KP.3 and JN.1, may allow it to spread more quickly.