Jun Hang - Academia.edu (original) (raw)
Papers by Jun Hang
Figure S2. Alignment of canine calicivirus (CaCV) major capsid protein VP1 sequences. The MUSCLE ... more Figure S2. Alignment of canine calicivirus (CaCV) major capsid protein VP1 sequences. The MUSCLE program in software Geneious version 10.0.9 was used in multi-sequence alignment of capsid proteins of CaCV type I viruses A128T, L198Â T and 48, and type II viruses W191R, 2117, and 3â 68. The amino acid residues differing between strains are shown in color. (DOC 559 kb)
Gene, 2014
Whole genome sequencing of six diagnostic brucellaphages, Tbilisi (Tb), Firenze (Fz), Weybridge (... more Whole genome sequencing of six diagnostic brucellaphages, Tbilisi (Tb), Firenze (Fz), Weybridge (Wb), S708, Berkeley (Bk) and R/C, was followed with genomic comparisons including recently described genomes of the Tb phage from Mexico (Tb M) and Pr phage to elucidate genomic diversity and candidate host range determinants. Comparative whole genome analysis revealed high sequence homogeneity among these brucellaphage genomes and resolved three genetic groups consistent with defined host range phenotypes. Group I was comprised of Tb and Fz phages that are predominantly lytic for Brucella abortus and Brucella neotomae; Group II included Bk, R/C, and Pr phages that are lytic mainly for B. abortus, Brucella melitensis and Brucella suis; Group III was comprised of Wb and S708 phage that are lytic for B. suis, B. abortus and B. neotomae. We found that the putative phage collar protein is a variable locus with features that may be contributing to the host specificities exhibited by different brucellaphage groups. The presence of several candidate host range determinants is illustrated herein for future dissection of the differential host specificity observed among these phages. Highlights The genomes of six brucellaphages in five of the six typing groups were sequenced. Comparisons were made of these six new genomes and two previously sequenced. High sequence identity was observed across brucellaphages of differing origin. Differences were in tail fiber, DNA polymerase, major head and phage collar genes. These variable loci may be under adaptive selection for host specificity.
Emerging Infectious Diseases, 2020
During 2017–2018, Barmah Forest virus was recovered from mosquitoes trapped in military training ... more During 2017–2018, Barmah Forest virus was recovered from mosquitoes trapped in military training areas in Australia and from a soldier infected at 1 of these areas. Phylogenies of the nucleotide sequences of the envelope glycoprotein gene E2 and the 3′ untranslated region suggest that 2 lineages are circulating in eastern Australia.
Journal of Biological Chemistry, 2000
Viruses, 2021
Influenza B viruses (IBVs) are causing an increasing burden of morbidity and mortality, yet the p... more Influenza B viruses (IBVs) are causing an increasing burden of morbidity and mortality, yet the prevalence of culture-adapted mutations in human seasonal IBVs are unclear. We collected 368 clinical samples from patients with influenza-like illness in Missouri during the 2019–2020 influenza season and recovered 146 influenza isolates including 38 IBV isolates. Of MDCK-CCL34, MDCK-Siat1, and humanized MDCK (hCK), hCK showed the highest virus recovery efficiency. All Missourian IBVs belonged to the Victoria V1A.3 lineage, all of which contained a three-amino acid deletion on the HA protein and were antigenically distant from the Victoria lineage IBV vaccine strain used during that season. By comparing genomic sequences of these IBVs in 31 paired samples, eight cell-adapted nonsynonymous mutations were identified, with the majority in the RNA polymerase. Analyses of IBV clinical sample–isolate pairs from public databases further showed that cell- and egg-adapted mutations occurred more ...
Sheng wu hua xue yu sheng wu wu li xue bao Acta biochimica et biophysica Sinica, 1998
In order to enhance the thermostability of D-glucose isomerase (GI), Gly 138 was decided to be th... more In order to enhance the thermostability of D-glucose isomerase (GI), Gly 138 was decided to be the target to be replaced by molecular design. The mutant G138P was obtained by in vitro site-directed mutagenesis of GI gene. The recombinant plasmid pTKD-GI containing mutant site was expressed in E. coli K38 strain. The comparison experiments of GIG138P with wild-type GI showed that: (1) The half time of GIG138P was as about two times as that of the wild type. (2) The optimum temperature of GIG138P was increased by 10-12 degrees. (3) The specific-activity of GIG138P was similar to the wild-type GI. We supposed, based on the above facts, that the substitution of Pro for Gly at position 138 introduced a pyrrolidine ring, which could just fill perfectly the empty hole leaved by Gly-138 which has no side chain and could make the protein structure more rigid, therefore the mutant G138P enhanced the thermostability of SM33GI.
Journal of Allergy and Clinical Immunology, 2020
RATIONALE: Respiratory diseases, including asthma, cause significant morbidity and mortality worl... more RATIONALE: Respiratory diseases, including asthma, cause significant morbidity and mortality worldwide and may result from the interplay between endogenous and exogenous factors. Staphylococcus aureus (SA), an opportunistic pathogen, and eosinophilia, a marker of inflammation, are both associated with allergic diseases and may be two such factors. Therefore, we hypothesized that elevated eosinophils could impact the relationship between SA and chronic respiratory diseases. METHODS: SA nasal colonization, inflammatory markers, and respiratory outcome data were obtained from the National Health and Nutrition Examination Survey 2001-04. Relationships between SA and respiratory outcomes (e.g. asthma, wheeze, and exacerbation-related morbidities) were evaluated via logistic regression, controlling for demographics, household smoking, recent respiratory illness, healthcare visits, and poverty-income ratio. Eosinophilia (>300cells/mL) was explored as a confounder and modifier of the SA-respiratory relationship. RESULTS: Eosinophils modified the relationship between SA and 8 of 9 respiratory outcomes. For example, asthma prevalence among those with both SA and eosinophilia was 15.7%; compared to neither factor (6.5%), SA-only (6.5%), or eosinophilia-only (11.1%), p50.03 for interaction. Similarly, SA was associated with 25% higher odds of taking medication for wheezing among those with eosinophilia [OR 1.25, 95% Confidence Interval (CI): 0.77, 2.03], but only 8% among those without [OR 1.08, 95%CI: 0.71, 1.62], p50.04 for interaction. CONCLUSIONS: SA was associated with higher odds of respiratory outcomes among US residents with eosinophilia, suggesting the importance of an allergic immune profile to the SA-respiratory relationship. Future longitudinal studies should evaluate if SA plays a causal role in respiratory disease among those with allergic disease.
Genome Announcements, 2017
A candidate new canine picornavirus was isolated from a respiratory swab collected from an Americ... more A candidate new canine picornavirus was isolated from a respiratory swab collected from an American foxhound ( Canis lupus familiaris ) in 1968. The assembled genome sequence of strain A128thr is 7,618 bases in length, comprising a complete protein-coding sequence of the 2,213-amino-acid polyprotein and partial terminal untranslated sequences.
Journal of Medical Entomology, 2021
In a follow-up to the investigations of soft ticks identified from seabird nest soil and litter c... more In a follow-up to the investigations of soft ticks identified from seabird nest soil and litter collected from coastal islands of the Republic of Korea (ROK), Ornithodoros sawaii and Ornithodoros capensis were assessed for the presence and identification of rickettsiae. Ticks collected from samples of 50–100 g of nest litter and soil from seabird nests were identified individually by morphological techniques, and species confirmed by sequencing of the mt-rrs gene. Subsequently, tick DNA preparations were screened for the presence of rickettsiae using a genus-specific nested PCR (nPCR) assay targeting the 17 kDa antigen gene. The amplicons from the 17 kDa assay and two additional nPCR assays targeting the gltA and ompB gene fragments were sequenced and used to identify the rickettsiae. A total of 134 soft ticks belonging to two species, O. sawaii Kitaoka & Suzuki 1973 (n = 125) and O. capensis Neumann 1901 (n = 9), were collected. Rickettsia lusitaniae DNA was detected and identified...
Systematic and Applied Acarology, 2017
The 65th Medical Brigade and Medical Department Activity-Korea, in collaboration with the Migrato... more The 65th Medical Brigade and Medical Department Activity-Korea, in collaboration with the Migratory Birds Research Center, National Park Research Institute, conducted a migratory bird tick-borne disease surveillance program during 2014–2015 on two small, remote, uninhabited islands, Hong (Gull) Island, southern Gyeongnam Province, and Nan Island, western Chungnam Province, Republic of Korea (ROK). Argasid ticks were collected from Black-tailed Gull (Larus crassirostris) nestlings that had recently died and associated nest soil/litter, and all tick life history stages were identified morphologically. Because morphological keys are unreliable for the identification of adult and nymphal argasid ticks, identifications were confirmed by genotyping using polymerase chain reaction techniques. A total of 29 Ornithodoros capensis larvae and 2 Ornithodoros sawaii larvae were collected from 4 of 7 (57.1%) Black-tailed Gull nestlings that had recently died. An additional five O. capensis (2 mal...
ABSTRACTIntra-host single nucleotide variants (iSNVs) have been increasingly used in genomic epid... more ABSTRACTIntra-host single nucleotide variants (iSNVs) have been increasingly used in genomic epidemiology to increase phylogenetic resolution and reconstruct fine-scale outbreak dynamics. These analyses are preferably done on sequence data from direct clinical samples, but in many cases due to low viral loads, there might not be enough genetic material for deep sequencing and iSNV determination. Isolation of the virus from clinical samples with low passage number increases viral load, but to date, no studies have investigated how dengue virus (DENV) culture isolation from a clinical sample impacts the consensus sequence, and there is no information on the intra-host virus population changes that may result from viral isolation. In this study, we investigate consensus and iSNV frequency differences between DENV sequenced directly from clinical samples and their corresponding low-passage isolates. Twenty five DENV1 and DENV2 positive sera and their corresponding viral isolates (T.sple...
American Journal of Tropical Medicine and Hygiene, 2013
Plasmodium ovale is one of several clinically relevant malaria species known to cause disease in ... more Plasmodium ovale is one of several clinically relevant malaria species known to cause disease in humans. However, in contrast to Plasmodium falciparum and Plasmodium vivax, which are responsible for most cases of human malaria, P. ovale has a wide distribution but low prevalence in tropical regions. Here, we report the case of a soldier returning from Liberia with P. ovale wallikeri malaria. This case highlights the limitations of both microscopy and the malaria rapid diagnostic test for diagnosing infection with P. ovale and for distinguishing P. ovale wallikeri from P. ovale curtisi. To our knowledge, this is the first case report in which quantitative real-time polymerase chain reaction amplification using the Cytochrome B gene, coupled with genomic sequencing of the potra locus, was used for definitive diagnosis of P. ovale wallikeri malaria.
The Journal of general virology, 2017
Flaviviruses comprise a large and diverse group of positive-stranded RNA viruses, including tick-... more Flaviviruses comprise a large and diverse group of positive-stranded RNA viruses, including tick-, mosquito- and unknown-vector-borne flaviviruses. A novel flavivirus was detected in pools of Aedes vexans nipponii (n=1) and Aedes esoensis (n=3) collected in 2012 and 2013 near the demilitarized zone (DMZ), Republic of Korea (ROK). Phylogenetic analyses of the NS5, E gene and complete polyprotein coding sequence (CDS) showed that the novel virus fell within the Aedes-borne flaviviruses (ABFVs), with nucleotide identity ranging from 57.8-75.1 %, 46.1-74.2 % and 51.1-76.2 %, respectively. While the novel ABFV was distant from other flaviviruses within the group, it formed a clade with Ilomantsi virus (ILOV). Sequence alignments of the partial NS5 gene, full-length E gene and polyprotein CDS between the novel virus and ILOV showed approximately 76.2 % nucleotide identity and 90 % amino acid identity, respectively. The ABFV identified in Aedes mosquitoes from the ROK is a novel ABFV based...
Journal of Medical Virology, 2021
Molecular Ecology, 2021
Recent outbreaks of emerging and re‐emerging viruses have shown that timely detection of novel ar... more Recent outbreaks of emerging and re‐emerging viruses have shown that timely detection of novel arboviruses with epidemic potential is essential to mitigate human health risks. There are rising concerns that emergent JEV genotype V (GV) is circulating in Asia, against which current vaccines may not be efficacious. To ascertain if JEV GV and other arboviruses are circulating in East Asia, we conducted next‐generation sequencing on 260 pools of Culex tritaeniorhynchus and Culex bitaeniorhynchus mosquitoes (6540 specimens) collected at Camp Humphreys, Republic of Korea (ROK) in 2018. Interrogation of our data revealed a highly abundant and diverse virosphere that contained sequences from 122 distinct virus species. Our statistical and hierarchical analysis uncovered correlates of potential health, virological, and ecological relevance. Furthermore, we obtained evidence that JEV GV was circulating in Pyeongtaek and, retrospectively, in Seoul in 2016 and placed these findings within the context of human and fowl reservoir activity. Sequence‐based analysis of JEV GV showed a divergent genotype that is the most distant from the GIII‐derived live attenuated SA14‐14‐2 vaccine strain and indicated regions probably responsible for reduced antibody affinity. These results emphasize recent concerns of shifting JEV genotype in East Asia and highlight the critical need for a vaccine proven efficacious against this re‐emergent virus. Together, our one‐health approach to Culex viral metagenomics uncovered novel insights into virus ecology and human health.
Inpatient COVID-19 cases present enormous costs to patients and health systems. Many hospitalized... more Inpatient COVID-19 cases present enormous costs to patients and health systems. Many hospitalized patients may still test COVID-19 positive, even after resolution of symptoms. Thus, a pressing concern for clinicians is the safety of discharging these asymptomatic patients if they have any remaining infectivity. This case report explores the viral viability in a patient with persistent COVID-19 over the course of a two-month hospitalization. Positive nasopharyngeal swab samples, analyzed by quantitative reverse transcription polymerase chain reactions (qRT-PCR), were collected and isolated in the laboratory, and infectious doses were analyzed throughout the hospitalization period. The patient experienced waning symptoms by hospital day 40 and had no viable virus growth in the laboratory by hospital day 41, suggesting no risk of infectivity, despite positive RT-PCR results, which prolonged his hospital stay. Notably, this case showed infectivity for at least 24 days from disease onset...
Viruses, 2019
Arboviruses continue to be a significant global health concern. The unbiased metagenomic analyses... more Arboviruses continue to be a significant global health concern. The unbiased metagenomic analyses of mosquito-borne and mosquito-specific viruses are useful to understand viral diversity and for the surveillance of pathogens of medical and veterinary importance. Metagenomic analysis was conducted on 6368 mosquitoes (736 pools), covering 16 species from 18 locations throughout the Republic of Korea (ROK) in 2016. In this report, we describe three viruses detected in a single pool of Aedes vexans nipponii collected at Yongsan U.S. Army Garrison, located in a densely populated district of Seoul, the ROK. The three novel viruses, designated as Yongsan bunyavirus 1 (YBV1), Yongsan picorna-like virus 3 (YPLV3) and Yongsan sobemo-like virus 1 (YSLV1), share sequence and structural characteristics with members belonging to the family Bunyaviridae, order Picornavirales, and family Solemoviridae, with shared RNA-dependent RNA polymerase (RdRp) amino acid identities of 40%, 42% and 86%, respec...
PloS one, 2018
Group C orthobunyaviruses (GRCVs) are a complex of viruses in the genus Orthobunyavirus and are a... more Group C orthobunyaviruses (GRCVs) are a complex of viruses in the genus Orthobunyavirus and are associated with human febrile disease in tropical and subtropical areas of South and Central America. While numerous GRCVs have been isolated from mosquitoes, animals, and humans, genetic analysis of these viruses is limited. In this study, we characterized 65 GRCV isolates from febrile patients identified through clinic-based surveillance in the northern and southern Peruvian Amazon. A 500 base pair region of the S segment and 750 base pair regions of the M and L segments were sequenced. Pairwise sequence analysis of the clinical isolates showed nucleotide identities ranging from 68% to 100% and deduced amino acid sequence identities ranging from 72% to 100%. Sequences were compared with reference strains of the following GRCVs: Caraparu virus (CARV), Murutucu virus (MURV), Oriboca virus (ORIV), Marituba virus (MTBV), Itaqui virus (ITQV), Apeu virus (APEUV), and Madrid virus (MADV). Sequ...
Virology journal, Feb 23, 2018
Vesiviruses (family Caliciviridae) had been shown capable of invading a variety of host species, ... more Vesiviruses (family Caliciviridae) had been shown capable of invading a variety of host species, raising concern of their zoonotic potential. Since the 1980's, several canine caliciviruses (CaCV) isolates have been reported and are phylogenetically related to the vesiviruses with features distinct from both Vesicular exanthema of swine virus (VESV) and Feline calicivirus (FCV) species in phylogeny, serology and cell culture specificities. Etiological studies of canine diseases in dogs used for military services and laboratory studies were conducted in 1963-1978 at the Walter Reed Army Institute of Research. Multiple known and unknown viral pathogens including caliciviruses were recovered. Four unidentified isolates were recovered in Walter Reed Canine Cells (WRCC) from respiratory, fecal and penile specimens. Physicochemical tests, electron microscopy, viral cultivation in human and animal cells, antibody neutralization assays, and recently the genome sequencing were used to cha...
Figure S2. Alignment of canine calicivirus (CaCV) major capsid protein VP1 sequences. The MUSCLE ... more Figure S2. Alignment of canine calicivirus (CaCV) major capsid protein VP1 sequences. The MUSCLE program in software Geneious version 10.0.9 was used in multi-sequence alignment of capsid proteins of CaCV type I viruses A128T, L198Â T and 48, and type II viruses W191R, 2117, and 3â 68. The amino acid residues differing between strains are shown in color. (DOC 559 kb)
Gene, 2014
Whole genome sequencing of six diagnostic brucellaphages, Tbilisi (Tb), Firenze (Fz), Weybridge (... more Whole genome sequencing of six diagnostic brucellaphages, Tbilisi (Tb), Firenze (Fz), Weybridge (Wb), S708, Berkeley (Bk) and R/C, was followed with genomic comparisons including recently described genomes of the Tb phage from Mexico (Tb M) and Pr phage to elucidate genomic diversity and candidate host range determinants. Comparative whole genome analysis revealed high sequence homogeneity among these brucellaphage genomes and resolved three genetic groups consistent with defined host range phenotypes. Group I was comprised of Tb and Fz phages that are predominantly lytic for Brucella abortus and Brucella neotomae; Group II included Bk, R/C, and Pr phages that are lytic mainly for B. abortus, Brucella melitensis and Brucella suis; Group III was comprised of Wb and S708 phage that are lytic for B. suis, B. abortus and B. neotomae. We found that the putative phage collar protein is a variable locus with features that may be contributing to the host specificities exhibited by different brucellaphage groups. The presence of several candidate host range determinants is illustrated herein for future dissection of the differential host specificity observed among these phages. Highlights The genomes of six brucellaphages in five of the six typing groups were sequenced. Comparisons were made of these six new genomes and two previously sequenced. High sequence identity was observed across brucellaphages of differing origin. Differences were in tail fiber, DNA polymerase, major head and phage collar genes. These variable loci may be under adaptive selection for host specificity.
Emerging Infectious Diseases, 2020
During 2017–2018, Barmah Forest virus was recovered from mosquitoes trapped in military training ... more During 2017–2018, Barmah Forest virus was recovered from mosquitoes trapped in military training areas in Australia and from a soldier infected at 1 of these areas. Phylogenies of the nucleotide sequences of the envelope glycoprotein gene E2 and the 3′ untranslated region suggest that 2 lineages are circulating in eastern Australia.
Journal of Biological Chemistry, 2000
Viruses, 2021
Influenza B viruses (IBVs) are causing an increasing burden of morbidity and mortality, yet the p... more Influenza B viruses (IBVs) are causing an increasing burden of morbidity and mortality, yet the prevalence of culture-adapted mutations in human seasonal IBVs are unclear. We collected 368 clinical samples from patients with influenza-like illness in Missouri during the 2019–2020 influenza season and recovered 146 influenza isolates including 38 IBV isolates. Of MDCK-CCL34, MDCK-Siat1, and humanized MDCK (hCK), hCK showed the highest virus recovery efficiency. All Missourian IBVs belonged to the Victoria V1A.3 lineage, all of which contained a three-amino acid deletion on the HA protein and were antigenically distant from the Victoria lineage IBV vaccine strain used during that season. By comparing genomic sequences of these IBVs in 31 paired samples, eight cell-adapted nonsynonymous mutations were identified, with the majority in the RNA polymerase. Analyses of IBV clinical sample–isolate pairs from public databases further showed that cell- and egg-adapted mutations occurred more ...
Sheng wu hua xue yu sheng wu wu li xue bao Acta biochimica et biophysica Sinica, 1998
In order to enhance the thermostability of D-glucose isomerase (GI), Gly 138 was decided to be th... more In order to enhance the thermostability of D-glucose isomerase (GI), Gly 138 was decided to be the target to be replaced by molecular design. The mutant G138P was obtained by in vitro site-directed mutagenesis of GI gene. The recombinant plasmid pTKD-GI containing mutant site was expressed in E. coli K38 strain. The comparison experiments of GIG138P with wild-type GI showed that: (1) The half time of GIG138P was as about two times as that of the wild type. (2) The optimum temperature of GIG138P was increased by 10-12 degrees. (3) The specific-activity of GIG138P was similar to the wild-type GI. We supposed, based on the above facts, that the substitution of Pro for Gly at position 138 introduced a pyrrolidine ring, which could just fill perfectly the empty hole leaved by Gly-138 which has no side chain and could make the protein structure more rigid, therefore the mutant G138P enhanced the thermostability of SM33GI.
Journal of Allergy and Clinical Immunology, 2020
RATIONALE: Respiratory diseases, including asthma, cause significant morbidity and mortality worl... more RATIONALE: Respiratory diseases, including asthma, cause significant morbidity and mortality worldwide and may result from the interplay between endogenous and exogenous factors. Staphylococcus aureus (SA), an opportunistic pathogen, and eosinophilia, a marker of inflammation, are both associated with allergic diseases and may be two such factors. Therefore, we hypothesized that elevated eosinophils could impact the relationship between SA and chronic respiratory diseases. METHODS: SA nasal colonization, inflammatory markers, and respiratory outcome data were obtained from the National Health and Nutrition Examination Survey 2001-04. Relationships between SA and respiratory outcomes (e.g. asthma, wheeze, and exacerbation-related morbidities) were evaluated via logistic regression, controlling for demographics, household smoking, recent respiratory illness, healthcare visits, and poverty-income ratio. Eosinophilia (>300cells/mL) was explored as a confounder and modifier of the SA-respiratory relationship. RESULTS: Eosinophils modified the relationship between SA and 8 of 9 respiratory outcomes. For example, asthma prevalence among those with both SA and eosinophilia was 15.7%; compared to neither factor (6.5%), SA-only (6.5%), or eosinophilia-only (11.1%), p50.03 for interaction. Similarly, SA was associated with 25% higher odds of taking medication for wheezing among those with eosinophilia [OR 1.25, 95% Confidence Interval (CI): 0.77, 2.03], but only 8% among those without [OR 1.08, 95%CI: 0.71, 1.62], p50.04 for interaction. CONCLUSIONS: SA was associated with higher odds of respiratory outcomes among US residents with eosinophilia, suggesting the importance of an allergic immune profile to the SA-respiratory relationship. Future longitudinal studies should evaluate if SA plays a causal role in respiratory disease among those with allergic disease.
Genome Announcements, 2017
A candidate new canine picornavirus was isolated from a respiratory swab collected from an Americ... more A candidate new canine picornavirus was isolated from a respiratory swab collected from an American foxhound ( Canis lupus familiaris ) in 1968. The assembled genome sequence of strain A128thr is 7,618 bases in length, comprising a complete protein-coding sequence of the 2,213-amino-acid polyprotein and partial terminal untranslated sequences.
Journal of Medical Entomology, 2021
In a follow-up to the investigations of soft ticks identified from seabird nest soil and litter c... more In a follow-up to the investigations of soft ticks identified from seabird nest soil and litter collected from coastal islands of the Republic of Korea (ROK), Ornithodoros sawaii and Ornithodoros capensis were assessed for the presence and identification of rickettsiae. Ticks collected from samples of 50–100 g of nest litter and soil from seabird nests were identified individually by morphological techniques, and species confirmed by sequencing of the mt-rrs gene. Subsequently, tick DNA preparations were screened for the presence of rickettsiae using a genus-specific nested PCR (nPCR) assay targeting the 17 kDa antigen gene. The amplicons from the 17 kDa assay and two additional nPCR assays targeting the gltA and ompB gene fragments were sequenced and used to identify the rickettsiae. A total of 134 soft ticks belonging to two species, O. sawaii Kitaoka & Suzuki 1973 (n = 125) and O. capensis Neumann 1901 (n = 9), were collected. Rickettsia lusitaniae DNA was detected and identified...
Systematic and Applied Acarology, 2017
The 65th Medical Brigade and Medical Department Activity-Korea, in collaboration with the Migrato... more The 65th Medical Brigade and Medical Department Activity-Korea, in collaboration with the Migratory Birds Research Center, National Park Research Institute, conducted a migratory bird tick-borne disease surveillance program during 2014–2015 on two small, remote, uninhabited islands, Hong (Gull) Island, southern Gyeongnam Province, and Nan Island, western Chungnam Province, Republic of Korea (ROK). Argasid ticks were collected from Black-tailed Gull (Larus crassirostris) nestlings that had recently died and associated nest soil/litter, and all tick life history stages were identified morphologically. Because morphological keys are unreliable for the identification of adult and nymphal argasid ticks, identifications were confirmed by genotyping using polymerase chain reaction techniques. A total of 29 Ornithodoros capensis larvae and 2 Ornithodoros sawaii larvae were collected from 4 of 7 (57.1%) Black-tailed Gull nestlings that had recently died. An additional five O. capensis (2 mal...
ABSTRACTIntra-host single nucleotide variants (iSNVs) have been increasingly used in genomic epid... more ABSTRACTIntra-host single nucleotide variants (iSNVs) have been increasingly used in genomic epidemiology to increase phylogenetic resolution and reconstruct fine-scale outbreak dynamics. These analyses are preferably done on sequence data from direct clinical samples, but in many cases due to low viral loads, there might not be enough genetic material for deep sequencing and iSNV determination. Isolation of the virus from clinical samples with low passage number increases viral load, but to date, no studies have investigated how dengue virus (DENV) culture isolation from a clinical sample impacts the consensus sequence, and there is no information on the intra-host virus population changes that may result from viral isolation. In this study, we investigate consensus and iSNV frequency differences between DENV sequenced directly from clinical samples and their corresponding low-passage isolates. Twenty five DENV1 and DENV2 positive sera and their corresponding viral isolates (T.sple...
American Journal of Tropical Medicine and Hygiene, 2013
Plasmodium ovale is one of several clinically relevant malaria species known to cause disease in ... more Plasmodium ovale is one of several clinically relevant malaria species known to cause disease in humans. However, in contrast to Plasmodium falciparum and Plasmodium vivax, which are responsible for most cases of human malaria, P. ovale has a wide distribution but low prevalence in tropical regions. Here, we report the case of a soldier returning from Liberia with P. ovale wallikeri malaria. This case highlights the limitations of both microscopy and the malaria rapid diagnostic test for diagnosing infection with P. ovale and for distinguishing P. ovale wallikeri from P. ovale curtisi. To our knowledge, this is the first case report in which quantitative real-time polymerase chain reaction amplification using the Cytochrome B gene, coupled with genomic sequencing of the potra locus, was used for definitive diagnosis of P. ovale wallikeri malaria.
The Journal of general virology, 2017
Flaviviruses comprise a large and diverse group of positive-stranded RNA viruses, including tick-... more Flaviviruses comprise a large and diverse group of positive-stranded RNA viruses, including tick-, mosquito- and unknown-vector-borne flaviviruses. A novel flavivirus was detected in pools of Aedes vexans nipponii (n=1) and Aedes esoensis (n=3) collected in 2012 and 2013 near the demilitarized zone (DMZ), Republic of Korea (ROK). Phylogenetic analyses of the NS5, E gene and complete polyprotein coding sequence (CDS) showed that the novel virus fell within the Aedes-borne flaviviruses (ABFVs), with nucleotide identity ranging from 57.8-75.1 %, 46.1-74.2 % and 51.1-76.2 %, respectively. While the novel ABFV was distant from other flaviviruses within the group, it formed a clade with Ilomantsi virus (ILOV). Sequence alignments of the partial NS5 gene, full-length E gene and polyprotein CDS between the novel virus and ILOV showed approximately 76.2 % nucleotide identity and 90 % amino acid identity, respectively. The ABFV identified in Aedes mosquitoes from the ROK is a novel ABFV based...
Journal of Medical Virology, 2021
Molecular Ecology, 2021
Recent outbreaks of emerging and re‐emerging viruses have shown that timely detection of novel ar... more Recent outbreaks of emerging and re‐emerging viruses have shown that timely detection of novel arboviruses with epidemic potential is essential to mitigate human health risks. There are rising concerns that emergent JEV genotype V (GV) is circulating in Asia, against which current vaccines may not be efficacious. To ascertain if JEV GV and other arboviruses are circulating in East Asia, we conducted next‐generation sequencing on 260 pools of Culex tritaeniorhynchus and Culex bitaeniorhynchus mosquitoes (6540 specimens) collected at Camp Humphreys, Republic of Korea (ROK) in 2018. Interrogation of our data revealed a highly abundant and diverse virosphere that contained sequences from 122 distinct virus species. Our statistical and hierarchical analysis uncovered correlates of potential health, virological, and ecological relevance. Furthermore, we obtained evidence that JEV GV was circulating in Pyeongtaek and, retrospectively, in Seoul in 2016 and placed these findings within the context of human and fowl reservoir activity. Sequence‐based analysis of JEV GV showed a divergent genotype that is the most distant from the GIII‐derived live attenuated SA14‐14‐2 vaccine strain and indicated regions probably responsible for reduced antibody affinity. These results emphasize recent concerns of shifting JEV genotype in East Asia and highlight the critical need for a vaccine proven efficacious against this re‐emergent virus. Together, our one‐health approach to Culex viral metagenomics uncovered novel insights into virus ecology and human health.
Inpatient COVID-19 cases present enormous costs to patients and health systems. Many hospitalized... more Inpatient COVID-19 cases present enormous costs to patients and health systems. Many hospitalized patients may still test COVID-19 positive, even after resolution of symptoms. Thus, a pressing concern for clinicians is the safety of discharging these asymptomatic patients if they have any remaining infectivity. This case report explores the viral viability in a patient with persistent COVID-19 over the course of a two-month hospitalization. Positive nasopharyngeal swab samples, analyzed by quantitative reverse transcription polymerase chain reactions (qRT-PCR), were collected and isolated in the laboratory, and infectious doses were analyzed throughout the hospitalization period. The patient experienced waning symptoms by hospital day 40 and had no viable virus growth in the laboratory by hospital day 41, suggesting no risk of infectivity, despite positive RT-PCR results, which prolonged his hospital stay. Notably, this case showed infectivity for at least 24 days from disease onset...
Viruses, 2019
Arboviruses continue to be a significant global health concern. The unbiased metagenomic analyses... more Arboviruses continue to be a significant global health concern. The unbiased metagenomic analyses of mosquito-borne and mosquito-specific viruses are useful to understand viral diversity and for the surveillance of pathogens of medical and veterinary importance. Metagenomic analysis was conducted on 6368 mosquitoes (736 pools), covering 16 species from 18 locations throughout the Republic of Korea (ROK) in 2016. In this report, we describe three viruses detected in a single pool of Aedes vexans nipponii collected at Yongsan U.S. Army Garrison, located in a densely populated district of Seoul, the ROK. The three novel viruses, designated as Yongsan bunyavirus 1 (YBV1), Yongsan picorna-like virus 3 (YPLV3) and Yongsan sobemo-like virus 1 (YSLV1), share sequence and structural characteristics with members belonging to the family Bunyaviridae, order Picornavirales, and family Solemoviridae, with shared RNA-dependent RNA polymerase (RdRp) amino acid identities of 40%, 42% and 86%, respec...
PloS one, 2018
Group C orthobunyaviruses (GRCVs) are a complex of viruses in the genus Orthobunyavirus and are a... more Group C orthobunyaviruses (GRCVs) are a complex of viruses in the genus Orthobunyavirus and are associated with human febrile disease in tropical and subtropical areas of South and Central America. While numerous GRCVs have been isolated from mosquitoes, animals, and humans, genetic analysis of these viruses is limited. In this study, we characterized 65 GRCV isolates from febrile patients identified through clinic-based surveillance in the northern and southern Peruvian Amazon. A 500 base pair region of the S segment and 750 base pair regions of the M and L segments were sequenced. Pairwise sequence analysis of the clinical isolates showed nucleotide identities ranging from 68% to 100% and deduced amino acid sequence identities ranging from 72% to 100%. Sequences were compared with reference strains of the following GRCVs: Caraparu virus (CARV), Murutucu virus (MURV), Oriboca virus (ORIV), Marituba virus (MTBV), Itaqui virus (ITQV), Apeu virus (APEUV), and Madrid virus (MADV). Sequ...
Virology journal, Feb 23, 2018
Vesiviruses (family Caliciviridae) had been shown capable of invading a variety of host species, ... more Vesiviruses (family Caliciviridae) had been shown capable of invading a variety of host species, raising concern of their zoonotic potential. Since the 1980's, several canine caliciviruses (CaCV) isolates have been reported and are phylogenetically related to the vesiviruses with features distinct from both Vesicular exanthema of swine virus (VESV) and Feline calicivirus (FCV) species in phylogeny, serology and cell culture specificities. Etiological studies of canine diseases in dogs used for military services and laboratory studies were conducted in 1963-1978 at the Walter Reed Army Institute of Research. Multiple known and unknown viral pathogens including caliciviruses were recovered. Four unidentified isolates were recovered in Walter Reed Canine Cells (WRCC) from respiratory, fecal and penile specimens. Physicochemical tests, electron microscopy, viral cultivation in human and animal cells, antibody neutralization assays, and recently the genome sequencing were used to cha...