A second wave of influenza is hitting doctors' offices and urgent care clinics nationwide, according to the latest national flu data.
“Seasonal influenza activity remains elevated and continues to increase across the country,” the Centers for Disease Control and Prevention reported Friday.
The new cases are coinciding with patients who were sick with the flu several weeks ago, and are now experiencing common complications. Up to a third of hospitalized flu patients develop bacterial pneumonia within a few weeks of their acute illness.
Positive flu tests on the rise
Nearly a third of flu tests came back positive during the week ending on Feb. 1, the CDC said, compared with a quarter of tests the previous week.
The agency estimated that there had been at least 24 million illnesses so far this season.
And, it seems, more people are getting sick.
An analysis of CDC data shows that cases of influenza-like illnesses in doctors offices and urgent care centers appear to be higher than they’ve been in at least 28 years — when the agency first started tracking the information.
No one can say why, as flu seasons vary greatly from year to year.
“I don’t think we know where the peaks are yet, which is a bit disconcerting,” said Dr. Cameron Wolfe, an infectious disease expert and professor of medicine at Duke University Medical Center in Durham, North Carolina.
So far this season, 13,000 people have died from the flu. With flu rates on the rise, the season isn't done.
“You have to figure that at least as many deaths are going to be in the second half” of the year, said Dr. Peter Hotez, dean of the National School of Tropical Medicine at Baylor College of Medicine and co-director of the Texas Children’s Hospital Center for Vaccine Development. “We’re probably looking at a 20- to 30,000 death flu season. That’s pretty significant."
Ten pediatric deaths were entered into the national database this week, bringing the total so far this season to 57.
Last year was particularly brutal, with 207 pediatric deaths reported.
Dr. Todd Rice, a professor of medicine in the division of allergy, pulmonary and critical care medicine at Vanderbilt University Medical Center in Nashville, Tennessee, said the current surge in flu could mean a “double hit” on hospitalizations. “It’s going to overlap considerably with the increase in bacterial pneumonias that we see routinely after flu peaks.”
That means more beds, more nurses and more ventilation will be needed for patients having trouble breathing because of the flu or other illnesses.
During any flu season, there may be several strains circulating. Flu A strains — which could cause more severe symptoms — make up nearly all cases going around right now, particularly H1N1 and H3N2. There were no new human cases of bird flu detected in the last week.
But the CDC did report the season's only case so far of a person with a different A strain variant: A(H1N2)v. (The "v" just means that it's a known variant of the flu virus and isn't considered new.)
The patient, a minor, became sick and was hospitalized in Iowa during the week of Jan. 18. The child has since recovered, the CDC said.
This particular variant was also detected last year in a child living near a pig farm in Pennsylvania. That child, who was vomiting and had a fever, cough and runny nose, was also hospitalized before getting better.
This variant infection is not related to the ongoing bird flu outbreak.
No illness was identified among the patient’s close contacts. No human-to-human transmission has been identified associated with this case.
Outside experts said they weren't surprised that the 2024 patient lived in the vicinity of a farm, as H1N2 mostly spreads among pigs. The latest child to become sick, however, didn't have any known contact with the animals.
It’s not unusual for flu variants to pop up from time to time, said Caitlin Rivers, an epidemiologist at the Johns Hopkins Center for Health Security, adding, though, that it's "a bit of a puzzle that the person had no contact with swine."
