Epidemiology of Echovirus 30 Infections Detected in a University Hospital in Catalonia, Spain, in 1995-2020

Abstract

There is a growing interest in echovirus 30 (E30), an enterovirus responsible for neurological disease and hospitalization. There are multiple studies of outbreaks, but few that study the epidemiology over long periods of time. Our study aims to describe the clinical, epidemiological and microbiological characteristics of a series of E30 infections detected over 26 years. Data were retrospectively collected from a database of all enterovirus infections identified in our laboratory. They were detected by viral isolation or nucleic acid detection in patients presenting with respiratory or neurological infections, rash, sepsis-like syndrome, or gastroenteritis. Enterovirus genotyping was performed by amplification of the VP1 gene using RT-nested PCR, followed by sequencing and BLAST analysis. Of the 2402 enterovirus infections detected, 1619 were linked to at least one genotype and 173 were caused by E30. Clinical information was available for 158 (91.3%) patients. E30 was associated with neurological infection in 107 (67.8%) cases and it was detected almost every year. Phylogenetic analysis was performed with 67 sequences. We observed that E30 strains circulating in Catalonia from 1996 to 2016 belong to two lineages (E and F), although the majority cluster was in F. In 2018, lineage I emerged as the dominant lineage.

Keywords: central nervous system; cerebrospinal fluid; echovirus 30; enteroviruses; epidemiology; phylogenetic analysis.

Figure 1

Annual distribution of E30 detections vs. other EV genotypes.

Figure 2

(a) Seasonal distribution of all E30 infections included in this study; (b) seasonal distribution of E30-positive cases with central nervous system (CNS) diseases versus other clinical presentations.

Figure 3

Phylogenetic tree of the 3′-VP1 region with E30 sequences from 1996–2020 classified into 9 lineages, A–I. The tree was reconstructed using the neighbor-joining method and the maximum composite likelihood model. The tree was rooted with the prototype sequences Bastianni (AF311938) and Frater (AF081341). Bootstrap resampling (1000 replicates) was used to determine grouping robustness. Values of >70% are shown. E30 sequences obtained in this study are colored according to the year of detection (yellow 1996–1997; green 2001–2006; red 2007–2009; violet 2010–2013; blue 2015–2018).