By Donald Gilpin

Flu, RSV (respiratory syncytial virus), and COVID-19 continue to spread throughout the region and the country.

The new COVID Omicron variant, XBB.1.5, which first appeared in the U. S. last fall, provides more evidence of COVID-19’s ability to evolve rapidly, as its many mutations help it to outmaneuver antibodies and immune defenses and spread broadly. XBB.1.5 currently accounts for more than 70 percent of all new COVID-19 cases in the northeast U.S.

Though cold weather and the holiday season invariably bring more outbreaks and viral spread as people gather indoors, fortunately the three viruses do not seem to rise and fall simultaneously.

Princeton Deputy Administrator for Health and Human Services Jeff Grosser explained the current status of epidemiological surveillance and the current outlook for Princeton and the region in facing the ongoing tripledemic.

“We certainly observed increases in respiratory illnesses in the weeks following both Thanksgiving and Christmas,” he wrote in an email.  The central west region of New Jersey, which includes Mercer County, was in low or moderate COVID-19 activity for most of November and December, he said, “But the last week of December we went to high and continue to sit there as of today (January 9).”

He continued, “Coupled with the high COVID-19 numbers we are seeing, flu rates throughout most of the fall were the highest we had seen in years. Fortunately, with the onslaught of new COVID-19 cases, we are beginning to see a decrease in flu and RSV cases.”

Grosser pointed out the effectiveness of the XBB.1.5 Omicron strain at evading antibodies. He warned, “Although flu and RSV cases are on the decline, COVID-19 cases have been ticking upwards and will likely result in increased hospitalizations.” He went on to emphasize how quickly, just in the past month, this surge in XBB cases has occurred, “yet another reminder of the importance of proper disease surveillance and adapting to the circulating strains.”

Dr. Craig Gronczewski, chief medical officer and vice president of medical affairs at Penn Medicine Princeton Health (PMPH), noted that patient volume at PMPH’s emergency department has recently been about 20 percent higher than anticipated, but he expressed confidence that the hospital will successfully meet the demand.

“We are increasing staff across the board — physicians, nurses, and patient care technicians — and repurposing some areas within the department to create additional space for patient care, when needed,” he wrote in a January 10 email.

“Hospitals across New Jersey are experiencing a surge in patients with respiratory infections, and Princeton Medical Center is no exception,” Gronczewski said. “Our emergency department has been busy for several weeks due to an influx of patients with influenza, COVID-19, and other respiratory infections such as RSV. We also are seeing patients with more severe illnesses who require complex care.”

Gronczewski added that PMPH has maintained policies such as universal masking to help protect patients, visitors, and staff members against the spread of respiratory infections.

In its most recent Influenza and Respiratory Illness Surveillance Report, for the week ending December 31, 2022, the New Jersey Department of Health cited a “high” level of influenza activity statewide, but influenza-related emergency department visits and outpatient provider visits lower than the previous week and lower than the same week in 2021. It went on to report three confirmed influenza-associated pediatric deaths this season, the first in the state in more than two years. There have been outbreaks of flu in all settings throughout the state.

The Princeton Health Department continues to be an important resource for the community regarding infectious diseases as it provides COVID-19 and flu vaccinations, with upcoming vaccination clinics listed on the health department website at princetonnj.gov and the NJ Vaccine Finder at covid19.nj.gov.

Grosser noted, “We continue to urge residents to stay home when sick, practice good hygiene like washing hands frequently, get vaccinated if you haven’t already, and anyone who has underlying illnesses should mask up during these surges in respiratory illnesses.”

Describing disease surveillance as “our best defense in recognizing new strains that could impact our public health approaches,” Grosser used a football metaphor, comparing disease surveillance to scouting another team before a big game. 

“In public health, prevention requires a game plan, and disease surveillance is similar to having the other team’s playbook and knowing what play is going to get called,” he said. “The players need to respond and adapt to each play. This is essentially community health precautions going into effect.”