Viruses associated with pneumonia in adults

Abstract

Viral pneumonia, which is typically associated with disease in childhood, is increasingly recognized as causing problems in adults. Certain viruses, such as influenza virus, can attack fully immunocompetent adults, but many viruses take advantage of more-vulnerable patients. The latter include patients receiving immunosuppressive therapy and elderly subjects, particularly those residing in long-term care facilities. The range of viruses producing pneumonia in adults includes common agents, such as varicella-zoster virus and influenza virus, as well as respiratory syncytial virus, human metapneumovirus, adenoviruses, picornaviruses, and coronaviruses. The roles played by other agents, such as rhinoviruses and human bocaviruses, in pneumonia are still under study. While therapy for most of theses agents, at least in adults, has not yet been fully clarified, it is reasonable to assume antivirals may work in certain situations if they are introduced early enough in the course of infection.

Figure 1.

Lung biopsy specimen from a patient with influenzal pneumonia, showing numerous necrotic cells in alveolar spaces, hyaline membranes, destruction of bronchial walls by neutrophils, and intra-alveolar hemorrhage, as well as occasional streptococcus pneumonia in alveolar spaces (kindly provided by Dr Fritz Lin, UCI Department of Pathology).