Non-COVID Respiratory Illness in a Post-Pandemic World: Practical Lessons and Future Directions

Amit Khanal^a, Bibhusan Basnet^b

^a Department of Internal Medicine, Wake Forest School of Medicine, Winston-Salem, NC, USA

^b Department of Hospital Medicine, Frye Regional Medical Center, Hickory, NC, USA

Background

COVID-19 pandemic has changed how we think about respiratory health. Now that COVID-19 restrictions have eased, other respiratory viruses like the flu and Respiratory Syncytial Virus (RSV) have come back stronger. There’s been a lot of talk, especially on social media, about human metapneumovirus (HMPV) becoming the next big threat, similar to COVID-19. [1]

Are Human Metapneumovirus and COVID-19 the Same?

While HMPV isn’t exactly the same as COVID-19, there are some similarities we should be aware of, especially with rising cases in places like China. The HPMV virus can cause breathing issues, mainly in kids, older adults, and those with weaker immune systems. It’s been around for a long time, but we’re hearing more about it now because doctors are testing for it more often. Like COVID-19, it spreads through coughing, sneezing, and touching contaminated surfaces. It usually starts with cold-like symptoms- runny nose, cough, sore throat, and sometimes a fever; but in severe cases, it can cause pneumonia or serious breathing problems. That’s why it’s essential to take it seriously. While HMPV and other viruses can make people sick, most healthy people recover on their own with rest, fluids, and medicine for fever. Unlike COVID-19, there is no vaccine for HMPV yet, but washing hands, covering coughs, and staying home when sick can help stop its spread. [2]

Rise of Flu - Why?

Flu cases have surged in the last few years, and the Centers for Disease Control and Prevention (CDC) has classified this flu season as “high severity” for all age groups. This reflects the elevated levels of influenza activity, hospitalizations, and deaths. The rise of flu is partly attributed to "immunity gaps" where populations had reduced exposure during pandemic lockdowns. You would be surprised to know that during the pandemic, mask-wearing and social distancing reduced flu infections but lowered natural immunity levels. The heightened focus on COVID-19 vaccinations may have contributed to declining flu vaccine uptake, leaving more individuals susceptible to influenza. [3]

As life returned to normal- schools reopened, workplaces filled up, and travel resumed- respiratory viruses got a chance to spread easily. To make matters worse, multiple viruses, including flu, RSV, and COVID-19, are circulating simultaneously, raising concerns about co-infections and their potential to cause more severe health outcomes. Furthermore, the reduced flu circulation during the pandemic may have influenced viral evolution, potentially affecting the effectiveness of pre-existing immunity. [4]

Masks: A Proven Tool Beyond Pandemics

One lesson we all learned from the pandemic is that masks are simple yet effective tools for reducing the spread of respiratory illnesses, including the flu. Studies have shown that even plain surgical masks help lower transmission. They not only protect the wearer but also reduce the likelihood of spreading infections, especially in crowded places or areas with poor ventilation. [5]

While face masks have declined, they remain essential in specific situations. Respiratory infections pose significant risks to immunocompromised individuals, older adults, and those with chronic health conditions. Simple measures, such as continued mask use in healthcare settings or during illness spikes, can protect these vulnerable groups. During respiratory illness surges, including flu and RSV outbreaks, masks can help reduce transmission. Some people may still want to wear a mask in crowded indoor places, especially if they are at higher risk of getting sick. It’s a personal choice, so you should decide what’s best for you based on your own health and situation. [6]

A Resilient Future for Public Health

The COVID-19 pandemic showed us that many illnesses that spread through the air aren’t just something we have to live with. We can lower our chances of getting sick by doing simple things like washing our hands, wearing masks, and staying home when we’re not feeling well. The question isn’t if masks work—we know they do. The real challenge is making them part of our response to outbreaks and high-risk situations. [7]

References

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3. Lozy T, Rimma Perotte, Eigen A, Eigen K, Kourgialis A, Scheinert T, et al. Changes in Seasonal Patterns for Common Pediatric Respiratory Viruses During the COVID Pandemic. Pediatric Emergency Care [Internet]. 2025 Feb 4 [cited 2025 Apr 2]; Available from: https://pubmed.ncbi.nlm.nih.gov/39902500
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6. Chu DK, Akl EA, Duda S, Solo K, Yaacoub S, Schünemann HJ. Physical distancing, face masks, and eye protection to prevent person-to-person transmission of SARS-CoV-2 and COVID-19: a systematic review and meta-analysis. The Lancet [Internet]. 2020 Jun 1;395(10242). Available from: https://www.thelancet.com/journals/lancet/article/PIIS0140-6736(20)31142-9/fulltext
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