Pediatric Infections by Human mastadenovirus C Types 2, 89, and a Recombinant Type Detected in Japan between 2011 and 2018.

Kenichiro Takahashi,Masami Konagaya,Miki Ogi,Gabriel Gonzalez,Naomi Nojiri,Tsuguto Fujimoto,Nozomu Hanaoka,Michael J Carr,Masaaki Kobayashi

doi:10.3390/v11121131

Abstract

Between 2011 and 2018, 518 respiratory adenovirus infections were diagnosed in a pediatric clinic in Shizuoka, Japan. Detection and typing were performed by partial sequencing of both hexon- and fiber-coding regions which identified: adenovirus type 1 (Ad-1, n = 85), Ad-2 (n = 160), Ad-3 (n = 193), Ad-4 (n = 18), Ad-5 (n = 27), Ad-11 (n = 2), Ad-54 (n = 3), and Ad-56 (n = 1). Considering previous reports of the circulation of an endemic recombinant Ad-2, e.g., Ad-89, 100 samples typed as Ad-2 were randomly selected for further molecular typing by sequencing the penton base-coding region. Despite the high nucleotide sequence conservation in the penton base- coding region, 27 samples showed 98% identity to Ad-2. Furthermore, 14 samples showed 97.7% identity to Ad-2 and 99.8% identity to Ad-89, while the remaining 13 samples showed an average 98% pairwise identity to other Ad-C types and clustered with Ad-5. The samples typed as Ad-89 (n = 14) and as a recombinant Ad type (P5H2F2) (n = 13) represented 27% of cases originally diagnosed as Ad-2, and were detected sporadically. Therefore, two previously uncharacterized types in Japan, Ad-89 and a recombinant Ad-C, were shown to circulate in children. This study creates a precedent to evaluate the epidemiology and divergence among Ad-C types by comprehensively considering the type classification of adenoviruses.

Highlights

Members of the Adenoviridae family are non-enveloped double-stranded DNA viruses with a size ranging from 70 to 90 nm
Considering that adenovirus type 2 (Ad-2) is the major source of respiratory infections in Japan, representing 26% of diagnosed adenovirus infections between 2008 and 2017 [9], and the previously reported evidence of recombinant forms of serotype Ad-2, we identified that the circulation of such recombinant types in Japan remains to be elucidated
The hexon partial sequences of such samples were submitted by BLAST to the International Nucleotide Sequence Database Consortium (INSDC) and determined the infecting types as: Ad-1 (n = 85), Ad-2 (160), Ad-3 (193), Ad-4 (18), Ad-5 (27), Ad-11 (2), Ad-54 (3), and Ad-56 (1), which were distributed in relatively comparable frequencies across the study years (Figure 1)

Summary

Introduction

Members of the Adenoviridae family are non-enveloped double-stranded DNA viruses with a size ranging from 70 to 90 nm. Viruses 2019, 11, 1131 cause a variety of diseases [1,2]. Human mastadenovirus C (Ad-C) types are associated with ~5% of upper respiratory tract infections and. ~15% of lower respiratory infections in children under the age of five [3,4]. Among Ad-C, adenovirus type 2 (Ad-2) is one of the most commonly detected types worldwide and is a leading pathogen associated with pediatric respiratory tract infections. Ad-C types are harbored as latent infections in tonsillar tissue and, are intermittently excreted in the feces of children [5]. Ad-2 ranks as the most frequently detected type in the Japanese surveillance of adenovirus infections [7], and a similar trend is observed in the United States of Diseases of Japan [9]

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Results

Discussion

Conclusion