Enterovirus D68-associated community-acquired pneumonia in children living in Milan, Italy

Background: An increasing number of children infected by enterovirus D68 (EV-D68) and affected by severe respiratory illness, muscle weakness and paralysis were described in the USA and Canada in 2014. Objectives: To investigate the potential involvement of EV-D68 in determining community-acquired pneumonia (CAP) in hospitalised children in order to acquire information concerning the clinical problems associated with EV-D68 in Italy. Study design: This prospective study of children hospitalised for CAP in the largest Pediatric Department in Milan, Italy, was carried out between 1 June and 31 December 2014. All of the children's admission nasopharyngeal swabs were investigated for the presence of EV-D68. Results: One hundred and seventy-six children with radiographically confirmed CAP were hospitalised during the 7-month study period: 97 (55.1%) had enterovirus/rhinovirus-positive nasopharyngeal samples, including four (2.3%) positive for EV-D68. These four samples were collected between 9 and 21 October, a month in which 21 cases of CAP were recorded. Phylogenetic analysis showed that all of the sequences fell into clade B. The most severe case was diagnosed in a 14-year-old girl with mitochondrial encephalopathy, lactic acidosis and stroke-like episodes (MELAS syndrome), who died after 12 days of hospitalisation. Conclusions: EV-D68 was detected in few children with usually mild-to-moderate lower respiratory tract infection, although the disease lead to the death of a girl with a severe chronic underlying disease. Further studies capable of better defining the epidemiological, genetic and pathogenetic characteristics of the virus are required in order to be able to prepare appropriate preventive and therapeutic measures.