Only 155 people were admitted to hospital for flu symptoms during last year's peak season.
According to health experts, the flu could rebound and there will be an estimated 600,000.
The number of COVID-19 hospitalizations in hospitals across the country is already overwhelming.
According to NBC News, public health experts believe that this flu season could lead to three times the number of hospitalizations than usual, which will put additional strain on the healthcare system during the pandemic.
According to the Centers for Disease Control, there have been between 9.3 and 45 million flu-related illnesses per year since 2010 and over 200,000 hospitalizations.
Officials from public health expected a "twindemic," but only 155 Americans were admitted to hospital for influenza last winter. This was at the peak flu season. This is compared to the 8,633 flu-stricken Americans who were hospitalized in the same period last year.
Experts believe that the lack of flu cases is due to COVID-19 measures such as mask-wearing or social distancing. Some are concerned that the decline in flu cases could lead to a rebound this season.
WTHR was told by Dr. Brian Dixon, Director of Public Health Informatics at Regenstrief Institute, that "the possibility of a ‘twindemic’ is very real this year."
Researchers from the University of Pittsburgh Graduate School of Public Health have published two new preprints that are not peer-reviewed and estimate that flu cases could increase by at least 20% this year, or, in the worst case, more than twice.
According to the analysis, hospitalizations could triple their normal level with 600,000 influenza hospitalizations.
In a press release, Dr. Mark Roberts, Director of the Public Health Dynamics Laboratory, University of Pittsburgh Graduate School of Public Health, stated that while COVID-19 measures will be relaxed, flu and other respiratory diseases will rebound, however, higher flu vaccination rates may help to reduce hospitalizations.
"In the worst-case scenario, with a highly transmissible flu virus dominating and low influenza vaccination, our predictive models suggest that there could be nearly half a million more flu hospitalizations than normal flu seasons. This scenario can be avoided by vaccinating as many people as possible against flu.
According to the University's analysis, 75% of Americans would need a flu shot in order to avoid this worst-case scenario. The CDC reported that 51.8% of Americans received a flu shot in the 2019-2020 flu season. Just over half were vaccinated.
David Kimberlin, codirector of the University of Alabama at Birmingham's division of pediatric infectious disease, said to NBC News that he has seen children enter the hospital for respiratory illnesses usually seen in winter like the respiratory syncytialvirus, croup, hand, foot and mouth disease.
In July, Dr. Sean O'Leary, a pediatric infectious disease physician at Children's Hospital Colorado, stated to NBC News that although there's no clear explanation for why these respiratory illnesses are spreading during the summer, he suggested that one possible reason was the loosening social distancing guidelines or mask-wearing.
He said, "There is more mixing between people than there used to be."
Kimberlin said that his Delta variant has overrun his hospital and warned that an increase in flu cases could be "catastrophic."
Over the past week, the US saw an average of 87,220 COVID-19 hospitalsizations. Some hospitals, particularly those in low-vaccination states, are near or at full capacity.