From the Guidelines
Respiratory viruses, particularly rhinoviruses, influenza viruses, and respiratory syncytial virus (RSV), are the primary viral causes of COPD exacerbations. Other significant viral pathogens include coronaviruses, parainfluenza viruses, adenoviruses, and human metapneumovirus 1. These viruses trigger exacerbations by infecting the respiratory epithelium, causing inflammation, increased mucus production, and bronchospasm, which worsen airflow limitation in already compromised COPD patients. According to a study published in the European Respiratory Journal, viruses are frequent microorganisms found in COPD exacerbations, with an incidence range of 39% and rhinovirus and RSV being the most frequent 1.
The risk of viral exacerbations increases during winter months when these respiratory viruses circulate more widely in the community. Prevention strategies include:
- Annual influenza vaccination, which has been shown to reduce the total number of exacerbations per vaccinated subject compared with those who received placebo (weighted mean difference [WMD], -0.37; 95% CI, -0.64 to -0.11; P = .006) 1
- Pneumococcal vaccination
- Good hand hygiene
- Avoiding contact with people who have respiratory infections
Early detection and treatment of viral exacerbations, including the use of antivirals like oseltamivir for influenza when appropriate, along with bronchodilators, corticosteroids, and supportive care, can help reduce the severity and duration of symptoms. It is essential to note that viral infections often lead to more severe and prolonged exacerbations compared to bacterial causes, highlighting the importance of prevention and early treatment strategies.
From the Research
Viruses Causing COPD Exacerbation
- Respiratory viruses are frequently detected in sputum from patients during COPD exacerbations, including influenza viruses, respiratory syncytial virus, and rhinoviruses 2, 3, 4
- Rhinoviruses are the most common virus type triggering COPD exacerbations 3, 4
- Influenza viruses also exacerbate COPD, with considerable morbidity and mortality 5
- Other viruses such as respiratory syncytial virus may also contribute to COPD exacerbations 2
Role of Viruses in COPD Exacerbations
- Experimental infection studies have established a causal relationship between virus infection and COPD exacerbations 3, 6
- Respiratory viruses trigger a substantial proportion of COPD exacerbations, with rhinoviruses being the most common type 3
- The host immune response to rhinovirus infection and abnormalities in host immunity may underlie increased susceptibility to virus infection in COPD 3
Treatment and Prevention
- Anti-viral treatments have not undergone clinical trials in COPD patients, but oseltamivir and zanamivir have been shown to be effective in treating influenza in COPD patients 5
- Experimental rhinovirus infection in COPD subjects offers a model to evaluate the effects of new treatments for virus-induced COPD exacerbations 6