What To Know About The New COVID Variant Dominating PA

PENNSYLVANIA — Pennsylvania has a new dominant, highly contagious variant of coronavirus that accounts for a about a third of all new COVID-19 infections, according to the latest CDC data.

The XBB.1.5 variant only made up 6 percent of total cases in the region at the start of December. It now accounts for 32.7 percent, more than any other strain. Pennsylvania's region for this CDC dataset also includes Delaware, the District of Columbia, Maryland, Virginia, and West Virginia, so details are inexact. But it's clear that shape of the virus in the area is changing.

The variant is related to XBB, a strain which caused case surges in 2022 in China.

Because of the variant's unusual mutation, many antibodies developed through vaccination and prior infection are less effective at neutralizing the virus, according to The Guardian. But there's no evidence that XBB.1.5 causes more serious disease than other omicron strain, and the COVID vaccines continue to reduce the likelihood of severe illness and death from the virus.

"We might certainly have a wave, but it’s just much less likely to be as deadly or overwhelming to a health care system compared to earlier waves before we had this degree of hybrid immunity," Dr. Isaach Bogoch, a University of Toronto epidemiologist, told NBC News.

Nationwide, XBB.1.5 accounted for 40.5 percent of all infections as of Saturday, becoming the nation's most common COVID strain. The variant represented only 21.7 percent of U.S. cases the week prior (Dec. 18-24), according to the CDC.

Officials have warned that while COVID-19 case rates have remained steady in Pennsylvania thus far this winter, there is a risk of hospitals being overloaded again because of other illnesses. Both influenza and respiratory syncytial virus (RSV) are already at near-record rates in the region, sparking concerns that a simultaneous rise in coronavirus cases could push healthcare facilities to the breaking point once again.

Rise of the subvariants

The XBB, BQ.1 and BQ.1.1 subvariants are currently the most antibody-resistant variants of COVID-19, according to a study published in the peer-reviewed journal Cell this month by scientists affiliated with Columbia University and the University of Michigan. This means that even those with the most recent booster vaccine meant to protect against the omicron variant as a whole are still experiencing breakthrough infections.

According to the CDC, the omicron variant spreads more easily than the original SARS-CoV-2 virus and the delta variant. However, symptoms are generally milder, and unlike the delta variation, the omicron strain often affects the upper-respiratory tract rather than the lungs, Dr. Karine Markosyan, a physician at the St. Gregory the Illuminator Medical Center, told Unicef in March.

Yale Medicine emphasizes that some people infected with omicron still develop severe disease and have to go to the hospital, and some die.

Repeated COVID infections also contribute "significant" short- and longterm risks of organ failure, according to a study from Washington University School of Medicine in St. Louis and the Veterans Affairs St. Louis Health Care system. For the study, researchers analyzed 5.8 million de-identified medical records in the U.S. Department of Veterans Affairs database.

"Without ambiguity, our research showed that getting an infection a second, third or fourth time contributes to additional health risks in the acute phase, meaning the first 30 days after infection, and in the months beyond, meaning the long COVID phase," said Dr. Ziyad Al-Aly, a clinical epidemiologist at the School of Medicine.

Still, the CDC says that being up to date on COVID-19 vaccination provides strong protection against severe disease, hospitalization, and death in all age groups.