WASHINGTON – A summer surge of COVID-19 is intensifying across the United States, according to the latest data from the Centers for Disease Control and Prevention (CDC). Driven by a new family of highly transmissible Omicron subvariants dubbed "FLiRT," the wave is marked by rising infection rates, increased hospital admissions, and a particularly concerning spike in emergency room visits for young children.

Public health officials are urging renewed caution, though they stop short of recommending broad mandates. The current situation underscores the virus's persistent ability to evolve and cause periodic waves of illness, even as the nation has largely moved on from the pandemic's emergency phase.

The Data Behind the Surge

The CDC's COVID Data Tracker, updated this week, paints a clear picture of a nationwide uptick. Key indicators have been trending upward for the past four to six weeks.

Nationally, the test positivity rate has climbed to 9.2%, up from a low of 4.5% in early June. Wastewater surveillance, a key early indicator of community spread, shows "high" or "very high" levels of viral activity in 38 states, with the most significant increases concentrated in the West and Southeast. States including California, Texas, Florida, and Arizona are reporting notable rises in metrics across the board.

Hospitalizations, while still far below the peaks seen in earlier years, have also risen. The CDC reported a 15% increase in new COVID-19 hospital admissions over the last week compared to the previous week, totaling approximately 12,000 new patients nationwide.

"This is not a repeat of 2020 or 2021, but it is a significant event that warrants our attention," said Dr. Eleanor Vance, an infectious disease specialist at the Johns Hopkins Bloomberg School of Public Health. "The virus is demonstrating its endemic nature, and these summer and winter waves may be a recurring pattern for the foreseeable future."

'FLiRT' Variants Fueling Transmission

The primary drivers of the current wave are the "FLiRT" variants, specifically KP.2 and its successor, KP.3. These descendants of the Omicron lineage contain key mutations in their spike proteins that appear to make them more adept at evading immunity from previous infections and vaccinations.

According to the CDC's genomic surveillance, KP.3 is now the dominant strain in the U.S., accounting for an estimated 40% of new infections. Its predecessor, KP.2, makes up another 25%.

"These variants are not necessarily causing more severe disease on an individual basis, but their increased transmissibility means more people are getting sick at once," Dr. Vance explained. "This naturally leads to a higher absolute number of severe outcomes and hospitalizations, which can strain local healthcare resources."

Alarming Rise in Pediatric ER Visits

One of the most troubling trends in the latest CDC report is a sharp increase in COVID-related emergency room visits for children under the age of 4. This demographic saw a 22% jump in ER visits over the past two weeks, a rate higher than any other age group.

While most young children experience mild, cold-like symptoms, health officials are concerned by the volume of cases. High fevers, dehydration, and respiratory distress are the primary reasons for emergency care visits.

"Young children, especially those under two, have less-developed immune systems and may not have been exposed to as many previous variants or vaccines," said a CDC spokesperson in a statement. "We urge parents to be vigilant for symptoms and to consult their pediatrician if their child's condition worsens, particularly if they experience difficulty breathing."

What Health Officials Recommend

In response to the surge, federal health agencies are reiterating established public health guidance. The CDC continues to recommend that all individuals six months and older stay up-to-date on their COVID-19 vaccinations, including the updated vaccine released last fall, which offers better protection against current variants.

Other recommendations include:

• Testing: Get tested for COVID-19 if you develop symptoms such as fever, cough, or sore throat.
• Isolation: If you test positive, follow CDC guidelines for isolation to prevent further spread.
• Masking: Consider wearing a high-quality mask in crowded indoor public spaces, especially if you or someone you live with is at high risk for severe disease.
• Ventilation: Improve ventilation by opening windows or using air purifiers to reduce the concentration of airborne virus particles.

As the summer continues, officials will closely monitor the trajectory of the wave, prepared to update guidance as the situation evolves.