Severe Infections with Human Adenovirus 7d in 2 Adults in Family, Illinois, USA, 2014

Abstract

Human adenovirus 7d, a genomic variant with no reported circulation in the United States, was isolated from 2 adults with severe respiratory infections in Illinois. Molecular typing identified a close relationship with strains of the same genome type isolated from cases of respiratory disease in several provinces of China since 2009.

Keywords: Illinois; United States; adenovirus; adenovirus 7d; family; respiratory infections; viruses.

Figure 1

Admission chest radiographs of 2 adults with severe infections with adenovirus type 7 in family, Illinois, USA, 2014. Chest radiograph of patient 1 shows diffuse parenchymal consolidation involving all lobes. Chest radiograph of patient 2 shows interstitial changes in all lung fields and cardiomegaly.

Figure 2

Timeline of events of 2 adults with severe infections with adenovirus type 7 in family, Illinois, USA, 2014. Shades of gray indicate different care units/wards in the hospital. RVP, respiratory virus panel; NMH, Northwestern Memorial Hospital (Chicago, IL, USA); ARDS, acute respiratory distress syndrome; ECMO, extracorporeal membrane oxygenation; ICU, intensive care unit; OH, outside hospital; SOB, shortness of breath.*Respiratory specimen positive for adenovirus by PCR.

Figure 3

Enzyme and phylogenetic analysis of human adenovirus 7 isolates from 2 patients in Illinois, USA, 2014, and comparison isolates. A) Restriction enzyme analysis of genomic DNA from human adenovirus 7 isolates from patients 1 and 2 (P1 and P2, father and son). Lane M, molecular mass marker. Values on the left are in basepairs. B) Virtual restriction enzyme analysis of 6 complete genomic sequence of adenovirus strain DG01 from China. Lane m, Molecular mass marker; lane 1, BamHI; lane 2, BclI; lane 3, BstEII; lane 4, HpaI; lane 5, SmaI. Values on the left are in basepairs. Phylogenetic analysis of C) hexon (HVR1–7) and D) fiber genes of adenovirus 7 strains from Asia and North America. Strains isolated in this study are indicated in bold. Phylogenetic trees were inferred by using the neighbor-joining method with 1,000 replicates. Bootstrap values are shown at branching points, and values <70% are not shown. Evolutionary distances were computed by using the Kimura 2-parameter method. There were 14 nt sequences and 1,509 positions in the final dataset for hexon gene analysis and 978 positions for fiber gene analysis. Analyses were conducted in MEGA6 (10). Hexon and fiber genes of human adenovirus 11p (strain Slobitski) were used as references. Scale bars indicate nucleotide substitutions per site.