Hospital-Acquired Respiratory Viral Infections: Incidence, Morbidity, and Mortality in Pediatric and Adult Patients

Chow, Eric J.; Mermel, Leonard A.

We identified 40 (32 definite and 8 possible) nosocomial viral respiratory tract infections in 38 patients during the study period, including 17 patients admitted to the adult hospital and 23 patients admitted to the pediatric hospital (5 and 44 cases per 10 000 admissions to the adult and pediatric hospital, respectively) ( Table 2 ). The median age of cases in the adult and pediatric hospitals was 56 and 1 year of age, respectively. Eleven (28%) of the cases were immunocompromised. In 6 cases, patients were in an ICU when they developed symptoms. In 5 other cases, after the nosocomial respiratory viral infection was identified, the patient was transferred to an ICU. The mean interval from symptom onset to ICU admission was 1.8 days. Two of these 5 cases, and 4 of the 10 cases already in an ICU, required mechanical ventilation after a mean interval of 5 and 0 days after symptom onset, respectively. In 17 of the 40 cases (43%), antibiotics were initiated at the time of symptom onset, and in 82% of the cases, the antibiotics were continued despite positive test results for the respiratory viral infection. It is unclear how many of these cases had bacterial coinfection. Fever (defined as temperature >38°C) and/or cough were the initial symptoms in over half of the cases (78% and 60%, respectively). Fever was the most common symptom among the pediatric patients (83%), whereas cough was the most common symptom among adult patients (77%). Congestion and rhinorrhea were present in 48% and 38% of patients, respectively. No adult patients had documented symptoms of vomiting or conjunctivitis associated with their viral infection; however, both were documented in pediatric patients (15% and 2.5%, respectively). No adult patients had a single isolated symptom at presentation, but fever was the only presenting symptom in 3 of the 23 pediatric cases. Forty-four viruses were identified in the 40 cases, including 4 cases of viral coinfection ( Table 3 ). The most common viruses identified were rhino/enterovirus in both adults (61%) and pediatric cases (54%). Influenza A only accounted for 3 cases (6.8%); no nosocomial influenza B cases were identified. During the study period, influenza activity was widespread in Rhode Island March 2, 2015 through April 1, 2016 per data from the Rhode Island Department of Health. Although 63% of cases occurred in the fall and winter, they were identified throughout the year (Figure 1) . Two adult and 3 pediatric patients (13%) died during the hospitalization involving rhino/enterovirus (2 adults, 1 pediatric patient), metapneumovirus (1 pediatric patient), and RSV (1 pediatric patient). The 3 pediatric patients were under 2 years of age. It is difficult to ascribe mortality to such infections in patients with multiple comorbidities; however, 1 pediatric patient with multiple congenital abnormalities decompensated shortly after the viral infection was diagnosed leading to intubation and extracorporeal membrane oxygenation (ECMO). The patient died 1 month after the respiratory virus testing was positive. Another pediatric patient with a hematologic malignancy decompensated shortly after the viral infection was diagnosed leading to intubation and ECMO. The patient died 11 days after respiratory virus testing was positive.