Viral Metagenomic Analysis of Cerebrospinal Fluid from Patients with Acute Central Nervous System Infections of Unknown Origin, Vietnam

Figure 1. Flowchart overview of diagnostic results for study of patients with suspected central nervous system infections admitted to 4 of 7 provincial hospitals, Vietnam, December 2012–October 2016. Inset map indicates places where samples were collected (red dots).

Figure 2. Number of cerebrospinal fluid samples with detected viruses by metagenomic next-generation sequencing and then confirmed by virus-specific PCR or reverse-transcription PCR, Vietnam, December 2012–October 2016. Samples were collected from patients with suspected central nervous system infection. For human papillomavirus, confirmatory testing was not performed because of the unavailability of a PCR assay.

Figure 3. Temporal distribution of enterovirus cases detected from cerebrospinal fluid samples of patients with suspected central nervous system infection by metagenomic next-generation sequencing and RT-PCR, Vietnam, December 2012–October 2016. Enterovirus RT-PCR results were obtained from the original study. RT-PCR, reverse transcription PCR. A) Combined data from 3 provinces; B) data from Hue province; C) data from Khanh Hoa province; D) data from Dak Lak province.

Figure 4. Phylogenetic tree of 298 complete viral protein 1 sequences of echovirus 30 (876 nt) isolated from cerebrospinal fluid samples of patients with suspected central nervous system infection, Vietnam, December 2012–October 2016. The inner color strip indicates 7 genogroups. The outer colorstrip indicates different countries of echovirus 30 isolates included in the tree. The outgroup is echovirus 21 Farina.