Infectious illness specialists say it's impossible to foresee what may happen next. Young children, in particular, remain vulnerable to respiratory viruses.
Emergency room visits for three of the most contagious viruses — the flu, respiratory syncytial virus, and COVID—are decreasing across the country.
But does this suggest that the feared "tripledemic" has passed? Experts disagree. Viruses are notoriously difficult to predict.
"We've all learned over the last several years that predicting COVID is like getting slapped in the face," said Dr. Katie Passaretti, vice president and enterprise chief epidemiologist for Atrium Health in Charlotte, North Carolina.
Nonetheless, hospital emergency room visits for the most serious viral dangers began to diminish in December, and the trend has continued this month. This is especially true when it comes to the flu.
Children were infected with two viruses.
Trying to predict how the flu will behave between now and the conclusion of flu season is "risky," according to Dr. William Schaffner, an infectious disease expert at Vanderbilt University Medical Center in Nashville, Tennessee. "No one can foretell what will happen next."
Dr. Christine Thomas, an epidemic intelligence service officer at the CDC who works with the Tennessee Department of Health, and Schaffner are co-authors.
"We were particularly curious to see what this year would look like," Thomas added, after several years with absolutely no flu.
Their study focused on 4,626 people in Tennessee who were given flu shots in mid-November. Flu, according to researchers, surged early and disproportionately affected children. According to a report published Thursday by the Centers for Disease Control and Prevention, children were twice as likely as adults to test positive, and they were sicker, especially if they were afflicted with multiple viruses at the same time, such as the common cold on top of flu.
Separate research published earlier this week discovered that children admitted to the hospital with Covid had more severe symptoms if they simultaneously had another infection.
Children under the age of five are especially vulnerable because their immature immune systems may not have been exposed to numerous common viruses during the pandemic.
"If you get a double infection, it tends to make you a little sicker, and you're more likely to stay in the hospital," Schaffner said.
According to the latest study, flu hospitalizations for very young children in Tennessee have already reached peak levels reported in previous poor flu seasons, at 12.6 per 100,000. This is consistent with national reports.
But the season is far from over. While A strains of the flu have been the most
common so far, B variants of the virus are more common by spring.
But the season is far from over. While A strains of the flu have been the most common so far, B variants of the virus are more common by spring.
"I believe we will have more hurdles in the road this respiratory virus season," Passaretti said. She was not a part of the new study.
Few people who tested positive for flu in Tennessee were vaccinated. Only 23% of children and 34% of adults had received flu vaccinations.
Furthermore, having influenza A does not confer immunity to the B strain. That instance, a person can contract the flu twice in one season.
"That's another reason to get vaccinated," Schaffner added. "Flu will probably not go away fully until early summer."
