The impact of virus infections on pneumonia mortality is complex in adults: a prospective multicentre observational study

Abstract

BackgroundVarious viruses are known to be associated with pneumonia. However, the impact of viral infections on adult pneumonia mortality remains unclear. This study aimed to clarify the effect of virus infection on pneumonia mortality among adults stratified by virus type and patient comorbidities.MethodsThis multicentre prospective study enrolled pneumonia patients aged ≥15 years from September 2011 to August 2014. Sputum samples were tested by in-house multiplex polymerase chain reaction assays to identify 13 respiratory viruses. Viral infection status and its effect on in-hospital mortality were examined by age group and comorbidity status.ResultsA total of 2617 patients were enrolled in the study and 77.8% was aged ≥65 years. 574 (21.9%) did not have comorbidities, 790 (30.2%) had chronic respiratory disease, and 1253 (47.9%) had other comorbidities. Viruses were detected in 605 (23.1%) patients. Human rhinovirus (9.8%) was the most frequently identified virus, followed by influenza A (3.9%) and respiratory syncytial virus (3.9%). Respiratory syncytial virus was more frequently identified in patients with chronic respiratory disease (4.7%) than those with other comorbidities (4.2%) and without comorbidities (2.1%) (p = 0.037). The frequencies of other viruses were almost identical between the three groups. Virus detection overall was not associated with increased mortality (adjusted risk ratio (ARR) 0.76, 95% CI 0.53–1.09). However, influenza virus A and B were associated with three-fold higher mortality in patients with chronic respiratory disease but not with other comorbidities (ARR 3.38, 95% CI 1.54–7.42). Intriguingly, paramyxoviruses were associated with dramatically lower mortality in patients with other comorbidities (ARR 0.10, 95% CI 0.01–0.70) but not with chronic respiratory disease. These effects were not affected by age group.ConclusionsThe impact of virus infections on pneumonia mortality varies by virus type and comorbidity status in adults.Electronic supplementary materialThe online version of this article (10.1186/s12879-017-2858-y) contains supplementary material, which is available to authorized users.

Effectiveness of inactivated influenza vaccine against laboratory-confirmed influenza pneumonia among adults aged ≥65 years in Japan

“…This single-center prospective study was conducted at Kameda Medical Center (KMC), Kamogawa, Chiba, Japan, as part of the Adult Pneumonia Study Group-Japan (APSG-J) Study [2,[11][12][13]. The APSG-J Study was a multicenter prospective study of adult pneumonia conducted at four community-based hospitals in Japan from September 2011 to August 2014.…”

“…If the patient was unable to cough up sputum, sputum was induced with the inhalation of hypertonic saline solution. Details of study settings and designs have been described previously [2,13].…”

“…Influenza infection is a threat to older adults because of its potential to cause pneumonia and secondary bacterial infections [13]. The burden of pneumonia is rapidly increasing in highincome countries such as Japan because of the aging population [2].…”

Проблема Бактериальных Осложнений При Респираторных Вирусных Инфекциях

“…Вирусные патогены были обнаружены в 23,1% случаев [49]. Риновирусы были наиболее ча-стой причиной развития пневмонии (9,8%), а вирусы гриппа и RSV встречались в 3,9% случаев каждый.…”

The problem of bacterial complications post respiratory viral infections

“…In a study performed in Japan that involved 2,617 elderly (≥65 years old) patients, diagnosed with chronic respiratory or other concomitant diseases, the viral pathogens were isolated in 23.1% of cases [49]. Rhinoviruses were the most common cause of pneumonia (9.8%), while both influenza and RSV were found in 3.9% of cases.…”