Viral pneumonia

• Published in: The Lancet (British edition) Vol. 377; no. 9773; pp. 1264 - 1275
• Main Authors: Ruuskanen, Olli, Prof, Lahti, Elina, MD, Jennings, Lance C, PhD, Murdoch, David R, Prof
• Format: Journal Article
• Language: English
• Published: Kidlington Elsevier Ltd 09-04-2011; Elsevier; Elsevier Limited
• Subjects: Adult; Age; Age Distribution; Age Factors; Algorithms; Antibiotics; Antiviral Agents - therapeutic use; Avian flu; Biological and medical sciences; biomarkers; Biomarkers - blood; Child; Children; Community-Acquired Infections - diagnosis; Community-Acquired Infections - epidemiology; Community-Acquired Infections - virology; Comorbidity; Data processing; Developing countries; Developing Countries - statistics & numerical data; Diagnosis, Differential; Epidemics; Epidemiology; Exo- alpha -sialidase; General aspects; Global Health; Human metapneumovirus; Human viral diseases; Humans; Immunocompetence; Industrialized nations; Infection; Infections; Infectious diseases; Influenza; Internal Medicine; LDCs; Lung - diagnostic imaging; Lung - pathology; Lung - virology; Medical sciences; Mortality; Pandemics; Parainfluenza; Pathogenesis; Pneumonia; Pneumonia, Bacterial - diagnosis; Pneumonia, Bacterial - epidemiology; Pneumonia, Bacterial - microbiology; Pneumonia, Bacterial - prevention & control; Pneumonia, Viral - diagnosis; Pneumonia, Viral - drug therapy; Pneumonia, Viral - epidemiology; Pneumonia, Viral - mortality; Pneumonia, Viral - prevention & control; Pneumonia, Viral - virology; Public health; Radiography; Respiratory syncytial virus; Rhinovirus; Seminar; Severe acute respiratory syndrome; Specimen Handling; Swine flu; United States - epidemiology; Vaccines; Viral diseases; Viral diseases of the respiratory system and ent viral diseases; Viral infections; Viruses; Medicine; Lung disease; Viral pneumonia; Respiratory disease
• ISSN: 0140-6736; 1474-547X
• DOI: 10.1016/S0140-6736(10)61459-6

Summary About 200 million cases of viral community-acquired pneumonia occur every year—100 million in children and 100 million in adults. Molecular diagnostic tests have greatly increased our understanding of the role of viruses in pneumonia, and findings indicate that the incidence of viral pneumonia has been underestimated. In children, respiratory syncytial virus, rhinovirus, human metapneumovirus, human bocavirus, and parainfluenza viruses are the agents identified most frequently in both developed and developing countries. Dual viral infections are common, and a third of children have evidence of viral-bacterial co-infection. In adults, viruses are the putative causative agents in a third of cases of community-acquired pneumonia, in particular influenza viruses, rhinoviruses, and coronaviruses. Bacteria continue to have a predominant role in adults with pneumonia. Presence of viral epidemics in the community, patient's age, speed of onset of illness, symptoms, biomarkers, radiographic changes, and response to treatment can help differentiate viral from bacterial pneumonia. However, no clinical algorithm exists that will distinguish clearly the cause of pneumonia. No clear consensus has been reached about whether patients with obvious viral community-acquired pneumonia need to be treated with antibiotics. Apart from neuraminidase inhibitors for pneumonia caused by influenza viruses, there is no clear role for use of specific antivirals to treat viral community-acquired pneumonia. Influenza vaccines are the only available specific preventive measures. Further studies are needed to better understand the cause and pathogenesis of community-acquired pneumonia. Furthermore, regional differences in cause of pneumonia should be investigated, in particular to obtain more data from developing countries.