Enterovirus D68 in Hospitalized Children, Barcelona, Spain, 2014-2021

Area of Science:

• Virology
• Epidemiology
• Infectious Diseases

Background:

• Enterovirus D68 (EV-D68) is a significant respiratory pathogen.
• Understanding its molecular epidemiology and clinical manifestations is essential for public health.
• Previous studies have highlighted the need for continued surveillance of EV-D68.

Purpose of the Study:

• To investigate the molecular epidemiology of EV-D68 infections.
• To describe the clinical features of EV-D68-associated respiratory cases.
• To assess the temporal trends and circulating subclades of EV-D68 in Barcelona.

Main Methods:

• Retrospective review of EV-D68-associated respiratory cases from 2014-2021.
• Real-time multiplex reverse transcription PCR for enterovirus detection.
• Phylogenetic analysis of the viral protein 1 (VP1) coding region for strain characterization.

Main Results:

• A total of 184 EV-D68 infections were identified, primarily in children (86%).
• Subclade B3 was dominant (80%), followed by D1 (17%), with shifting clade proportions over time.
• Biennial circulation patterns were observed (2016, 2018, 2021). Lower respiratory tract infections were common, necessitating pediatric intensive care unit admission in 11.8% and invasive mechanical ventilation in 2.3%. One case presented with neurologic complications.

Conclusions:

• EV-D68 infections in Barcelona during 2014-2021 were characterized by the predominance of subclade B3 and biennial outbreaks, mainly affecting children.
• The observed clinical spectrum ranged from lower respiratory tract infections to rare neurologic complications, underscoring the virus's potential neurotropism.
• Mandatory enterovirus surveillance is recommended due to the potential for severe outcomes and neuroinvasive disease.