Although a new coronavirus variety has taken hold, fewer patients are visiting hospitals this winter than in previous years.

The CDC’s wastewater data indicates “very high” levels of Covid activity.

Highlight

• JN.1 Variant Dominance:The JN.1 variant is now responsible for 62% of current Covid infections in the U.S., marking a rapid increase from 21% four weeks ago.
• Winter Covid Surge:
  • Winter Covid activity appears to surpass last year’s levels, as indicated by preliminary CDC estimates using wastewater data, though this data covers only around 40% of the U.S. population.
• Hospitalizations and Vaccine Effectiveness:
  • Hospitalizations have risen since November, but the severity per infection is lower than last year. The JN.1 variant may be more contagious, and updated vaccines seem to provide substantial protection against severe illness, though a significant portion of the population remains unvaccinated.

According to data issued by the Centers for Disease Control and Prevention on Friday, 62% of Covid infections in the United States are currently caused by the coronavirus variety that is spreading the quickest, JN.1.

The variation accounted for 39% of instances two weeks ago and 21% of cases four weeks ago.

Its ascent is happening quite quickly. Dr. Thomas Russo, head of infectious diseases at the University at Buffalo Jacobs School of Medicine and Biomedical Sciences, stated without a doubt.

Preliminary estimates from the CDC indicate that wastewater data indicates that this winter’s Covid activity has topped last winter’s. However, there are limitations to the data: It solely tracks activity among program participants who are linked to a municipal sewer system. Based on CDC estimates, this represents around 40% of the US population.

Scientists and medical professionals have cautioned in recent days that the outbreak this winter seems to be the biggest since the initial omicron wave two years ago.

Through email, a CDC representative stated that while it is currently too early to draw firm conclusions about how JN.1’s takeover compares to previous surges, “its projection is similar to BA.2, which predominated in March-May 2022.”

According to the spokesperson, “the initial emergence of the first omicron in November/December 2021 was much more dramatic.”

Hospitalizations for Covid have increased since the beginning of November. Based on an analysis by NBC News of the most recent Health and Human Services data available, new hospital admissions increased by 28% in the two-week period ending on December 30. However, they have not kept up with the infection rate increase.

Hospitalizations and serious illness measurements are almost 30% lower than they were this time last year. According to Katelyn Jetelina, an epidemiologist and scientific adviser to the CDC, “this basically means each infection is less likely to result in illness that requires medical care, which is welcoming news for our hospital systems and individuals alike.”

Given its dominance, JN.1 may be more contagious than other strains and is responsible for the emergence of new infections. It also had greater opportunity to spread during holiday get-togethers.

“Unless you get the most recent formulation that was released this autumn, the protection that we’ve built up from previous infection and immunizations is really fading over time,” Russo stated. “That is one of the reasons we will be more vulnerable to JN.1 infections.”

The CDC reports that the revised Covid vaccine seems to provide substantial protection against severe sickness caused by the new strain. Depending on a person’s vaccination and infection history, a preliminary study indicated that the revised vaccines from Moderna and Pfizer increased antibody protection against JN.1 by up to 13 times. However, the study hasn’t undergone peer review.

JN.1 shares some genetic similarities with XBB.1.5, the variation of omicron that the vaccination is intended to target. However, compared to XBB.1.5, JN.1 has almost thirty more mutations on its spike protein.

Only about 8% of children and over 19% of adults in the United States have not received an updated Covid vaccination.

“If you look at who is now dying from COVID, it’s our elderly, especially those who are 75 years of age and beyond. However, nobody is completely safe, not even young, healthy people, according to Russo. “Getting the new Covid vaccine is still an option.”

Russo stated that in light of past patterns, he does not anticipate JN.1 to prolong the winter Covid wave. Hospitalizations due to COVID-19 have peaked in early to mid-January for the past three years.

According to Jetelina, the number of instances is expected to peak the following week.

“You still have to descend the slope after reaching the summit. That essentially indicates that the Covid wave is still half over, she said.