In a groundbreaking study shedding light on the aftermath of viral infections, researchers have discovered that both COVID-19 and the seasonal flu can lead to persistent health problems long after the acute phase. The study, conducted on individuals hospitalized with either COVID-19 or the flu, reveals an increased risk of death, hospital readmission, and various health issues affecting organs such as the heart, lungs, brain, and kidneys.
One of the study’s authors, a clinical epidemiologist at a university in St. Louis, emphasized the substantial toll on health following hospitalization with either virus. “Many individuals think they’re over COVID-19 or the flu after being discharged from the hospital. That may be true for some, but our research shows that both viruses can cause long-haul illness,” the author stated.
The investigation was prompted by the prevalence of long COVID associated with the SARS-CoV-2 virus, leading researchers to examine the possibility of a “long flu.” The author noted that the study aimed to determine the extent of long-term health effects experienced by individuals with the flu.
Using records from a government health agency, researchers compared outcomes for approximately 11,000 individuals hospitalized with influenza from 2015 to 2019 and 81,000 individuals hospitalized with COVID-19 from 2020 to 2022. The analysis covered 94 different health risks, death rates, and hospital readmissions over an 18-month period post-infection.
Results indicated higher risks for COVID-19 in nearly every organ system compared to the flu. The flu exhibited a 6 percent elevated risk for health conditions in six of the 94 categories, primarily affecting the respiratory system. In contrast, COVID-19 posed a significantly higher risk for 64 complications, including fatigue, mental health problems, and issues with the lungs, gut, and heart.
Moreover, individuals with COVID-19 faced a 50 percent higher risk of death than those with the flu, translating to approximately eight more deaths per 100 individuals in the COVID-19 group. The COVID-19 group also experienced increased rates of hospital readmission and intensive care unit (ICU) admission, with 20 more hospital admissions and nine more ICU admissions per 100 individuals compared to the flu group.
The findings remained consistent across dominant variants, including pre-delta, delta, and omicron, and were observed in both vaccinated and unvaccinated individuals. However, the study’s limitations, such as its focus on hospitalized individuals and the absence of a control group, were acknowledged by the authors. The data’s bias toward older individuals of a specific gender also raised questions about the impact on individuals of other ages and sexes.
An expert in infectious diseases emphasized the seriousness of COVID-19 compared to the flu. “These findings really push back firmly and conclusively against statements like ‘COVID is just like the flu.’ It is not like the flu,” the expert stated.
The study’s lead researcher highlighted the need to recognize the long-term effects of viral infections, challenging the pre-pandemic perception that most viral infections were inconsequential. Recent studies have supported the idea that even routine viral infections can result in lingering symptoms and health issues.
The difficulty in distinguishing between long COVID and post-viral syndrome with influenza was acknowledged by experts. The infectious diseases expert explained that distinguishing specific effects of COVID-19 or the flu from general debilitation in a hospital setting can be challenging, especially for older individuals.
The study underscores the importance of prevention and treatment, with the expert emphasizing the need for higher vaccination rates. “This is a high-risk group — why isn’t that number higher? A lot of these illnesses could have been prevented by getting a COVID vaccine and a flu vaccine,” the expert urged.
In addition to prevention, timely treatment was highlighted as crucial. The expert pointed to the effectiveness of a medication in reducing the risk of adverse outcomes for COVID-19 patients. A real-world study reported a lower hospitalization rate within 30 days for individuals who took the medication within five days of a COVID-19 diagnosis compared to those who did not.
