Tailored Prevention, Care Necessary in Addressing Viral CAP

A new study of hospitalized adults found clear differences in how community-acquired pneumonia (CAP) caused by SARS-CoV-2, influenza, and respiratory syncytial virus (RSV) presents, how it’s managed, and how patients fare, which researchers say calls for pathogen-specific prevention and treatment.¹

“CAP is a significant global health challenge, accounting for an estimated 2 million deaths annually,” wrote authors of the study. “Viral pathogens are increasingly recognized in up to 26% of adult CAP hospitalizations, with influenza and RSV historically predominant in the pre-pandemic era.”

The retrospective cohort study from Humanitas Research Hospital in Milan evaluated 165 hospitalized adults with single-virus CAP. Researchers found that SARS-CoV-2 infection resulted in the highest in-hospital mortality rate at 20.9% and a 12-month mortality rate of 51.9%.¹

Conversely, influenza patients presented with higher acute risks, including a 21.1% rate of cardiovascular events, a 12.3% rate of intensive care unit admissions, and a 14% rate of secondary bacterial coinfections. RSV cases demonstrated lower initial severity, though all 3 pathogens heavily impacted elderly and comorbid populations.

READ MORE: Serotype 34 Causes Pneumococcal Meningitis in Child With Cochlear Implants

Health guidance from Cedars-Sinai notes that CAP develops outside health care settings, presenting with rapid-onset fever, cough, and dyspnea that can progress to respiratory failure, making early pathogen detection and targeted vaccination essential.²

Distinct Pathogen Profiles and Clinical Trajectories

Understanding these distinct viral trajectories allows health care teams to anticipate complications and tailor treatment strategies. The Italian cohort findings confirm that viral pneumonia cannot be managed with a single blanket strategy, as influenza presents elevated thrombo-inflammatory risks and SARS-CoV-2 drives long-term mortality.^1,3

Viral pathogens damage pneumocytes, induce airway inflammation, and impair gas exchange. Modern diagnostic tools, including rapid polymerase chain reaction testing and thin-section computed tomography scans, allow clinicians to identify viral etiologies quickly and differentiate them from primary bacterial infections.³

To assist clinicians in navigating these complex viral presentations, the American Thoracic Society updated its clinical practice guidelines for CAP. The guidelines suggest withholding empiric antibiotics in healthy outpatients with viral pneumonia to prevent unnecessary drug exposure.⁴

However, for hospitalized patients and outpatients with comorbidities, empiric antibacterial coverage is recommended due to the high threat of viral and bacterial coinfection. The guidelines also endorse point-of-care lung ultrasound as an acceptable diagnostic alternative to chest radiography when clinical expertise is available.

The Crucial Role of Pharmacist Stewardship

In hospital settings, clinical pharmacists play an essential role in optimizing pneumonia therapy and leading antimicrobial stewardship initiatives. A prospective study across 6 Cleveland Clinic hospitals evaluated an infectious disease pharmacist-led stewardship program that delivered 959 targeted intervention recommendations across 685 patient encounters.^3,5

Clinicians accepted 72% of pharmacist recommendations overall, demonstrating high receptivity in transitioning patients from intravenous to oral antibiotics at 80% acceptance and de-escalating extended-spectrum antibiotics at 78% acceptance.⁵

Although clinicians were less receptive to recommendations limiting treatment duration to 5 days, accepting 65% of those suggestions, current guidelines affirm that stable nonsevere pneumonia patients can be safely treated with short antibiotic courses lasting fewer than 5 days.^4,5

By evaluating patient stability daily and guiding appropriate drug selection, pharmacists bridge the gap between clinical guidelines and bedside care to ensure safe, individualized treatment.^3,5

“Our findings emphasize the heterogeneity of viral CAP in hospitalized adults. While SARS-CoV-2 is still associated with high long-term mortality, influenza and RSV also pose significant clinical challenges,” concluded authors of the current study.¹ “These data reinforce the need for pathogen-specific prevention and management strategies and suggest that long-term outcomes should be considered in the development of vaccination and therapeutic policies.”

READ MORE: Pneumococcal Resource Center

REFERENCES

1. Silani MS, Stainer A, Russo M, et al. Comparative outcomes of influenza, SARS-CoV-2, and respiratory syncytial virus community-acquired pneumonia: insights from an Italian retrospective cohort study. IJID Regions. October 1, 2026:101032. doi:10.1016/j.ijregi.2026.101032

2. Community-acquired pneumonia in adults. Cedars-Sinai. Accessed October 22, 2026. https://www.cedars-sinai.org/health-topics/community-acquired-pneumonia-in-adults

3. Freeman AM, Leigh, Jr TR. Viral pneumonia. [Updated 2023 Jul 4]. In: StatPearls [Internet]. Treasure Island (FL): StatPearls Publishing; 2023 Jan-. Available from: https://www.ncbi.nlm.nih.gov/books/NBK513286/

4. Jones BE, Ramirez JA, Oren E, et al. Diagnosis and management of community-acquired pneumonia: An official American Thoracic Society Clinical Practice guideline. AJRCCM. 2025;212(1):24-44. doi:10.1164/rccm.202507-1692st

5. Walker RE, Schulte R, Pallotta AM, et al. Acceptance of pharmacist-led stewardship recommendations for patients with community-acquired pneumonia. Antimicrob Steward Healthc Epidemiol. 2024;4(1):e181. 2024 Oct 17. doi:10.1017/ash.2024.399