A new study published in The Lancet this week indicates that influenza can also lead to persistent symptoms and long-term health consequences, similar to what has been seen in some COVID-19 patients. This raises concerns that ‘long flu’ could emerge as a significant public health issue alongside long COVID.
New Research Shows Increased Risk of Lingering Effects After Flu
Researchers in the UK analyzed data on nearly 19,000 patients hospitalized with influenza over a 20-year period from 1998-2018, examining health records for various diagnoses in the year following discharge.
The analysis showed that people hospitalized for influenza had a significantly increased risk of experiencing medical issues like heart failure, stroke, diabetes, kidney disease, and depression in the 12 months after discharge compared to other groups of patients [1]00684-9/fulltext).
Overall, flu patients had a 37% higher risk of death and were more than 2.5 times as likely to be diagnosed with conditions indicating long-term physical and mental health issues in the year following hospitalization.
Lead researcher Dr. Kenneth Baillie said:
“Influenza has generally not been thought of as a disease that leaves people with long-term consequences…But this study shows that for some people a severe case of influenza can lead to lingering health problems.”
These findings highlight another reason why preventing flu through vaccination is so critical, especially for vulnerable groups. Experts say the research also underscores the need to investigate post-viral syndromes beyond just COVID-19.
Experts Warn Flu Could Be Causing Unrecognized Cases of ‘Long Flu’
The patterns seen in the study are strikingly similar to what has occurred with long COVID, where patients experience fatigue, brain fog, weakness and damage to multiple organ systems after recovering from the acute infection.
Dr. Linda Geng of Stanford University commented on the findings:
“This study suggests that the phenomenon of long-term negative health consequences following viral infections is not exclusive to coronaviruses… it likely applies to influenza as well.”
There are likely many undiagnosed cases of ‘long flu’ already occurring, according to Dr. Eric Topol of Scripps Research:
“Long-haulers after flu has probably been right under our noses, but unrecognized due to the predominance of post-acute COVID illness.”
The research highlights the need to understand post-viral conditions beyond just COVID-19. Experts say long-term monitoring should become standard practice for severe influenza cases going forward.
Known Risk Factors for Long COVID Also Apply to Influenza
Interestingly, many of the same risk factors identified for long COVID also apply to long-term impacts from flu based on the study’s analysis. These include:
- Older age
- Pre-existing conditions like diabetes, lung disease, heart failure
- Increased severity of the initial influenza infection
People hospitalized in intensive care for flu appear much more likely to experience ongoing health problems. Almost 1 in 5 survivors of ARDS, a severe lung condition often occurring with influenza, had damage to multiple organs and cognitive issues a year later based on the data.
Overall, the study calculated that approximately 11% of flu patients hospitalized in intensive care still had abnormal lung scans a year after discharge, suggesting permanent loss of lung function.
Concerns Over Dual Winter Surges of COVID-19 and Influenza
The revelations around ‘long flu’ come at a concerning time as both COVID-19 and influenza are expected to surge this winter. New Omicron subvariants like BQ.1.1 are evading immunity and driving up COVID hospitalizations already.
Meanwhile, flu season started unusually early this fall and hospitalization rates have continued increasing nationwide over the past month, reaching levels not typically seen until December or January. The CDC estimates there have already been at least 8.7 million illnesses, 78,000 hospitalizations, and 4,500 deaths from flu so far this season.
Experts worry the combination of simultaneous influenza and COVID outbreaks could overwhelm hospitals which are already strained dealing with other respiratory viruses like RSV. There are also concerns about potential co-infections where patients contract influenza and COVID at the same time.
This makes prevention through vaccination and other measures like masking even more vital this winter. However, flu shot uptake remains low so far while many have dropped precautions like masking and distancing.
The revelations around long-term impacts from influenza provide yet another reason for people to take flu seriously and get their shot if they have not yet. Combating misinformation around seasonal flu being “just a bad cold” will be key according to public health experts.
While the full extent remains unknown, it appears influenza can no longer be thought of as just an acute illness that patients bounce back from. ‘Long flu’ is likely an unrecognized phenomenon that leaves some with chronic health issues in the months and years after infection, similar to long COVID.
Ongoing research in this area will be important, as will changing attitudes around flu vaccination and prevention measures. With the threat of prolonged COVID compounded by lingering effects from influenza, this winter and beyond seem fraught with risk for overwhelmed healthcare systems and patients alike.
To err is human, but AI does it too. Whilst factual data is used in the production of these articles, the content is written entirely by AI. Double check any facts you intend to rely on with another source.
