scholarly journals Clinical Features, Epidemiology, and Climatic Impact of Genotype-specific Human Metapneumovirus Infections: Long-term Surveillance of Hospitalized Patients in South Korea

2019 ◽  
Vol 70 (12) ◽  
pp. 2683-2694 ◽  
Author(s):  
Yong Kwan Lim ◽  
Oh Joo Kweon ◽  
Hye Ryoun Kim ◽  
Tae-Hyoung Kim ◽  
Mi-Kyung Lee
Keyword(s):  
South Korea ◽  
Clinical Characteristics ◽  
Large Scale ◽  
Sunshine Duration ◽  
Meteorological Data ◽  
Clinical Manifestations ◽  
Human Metapneumovirus ◽  
Hmpv Infection ◽  
Tract Infections

Abstract Background Human metapneumovirus (hMPV) commonly causes upper and lower respiratory tract infections. Here, we performed long-term retrospective surveillance of hMPV infection among patients hospitalized in South Korea between 2007 and 2016 and investigated seasonal dynamics and clinical characteristics associated with each virus subtype/genotype. Methods Patient specimens were tested for hMPV and other respiratory viruses by commercial molecular assays. Medical records of hMPV-positive patients were reviewed, and hMPV subtype/genotype analysis was performed. We also collected meteorological data and analyzed relationships with hMPV activity. Results Of 23 694 specimens, 1275 (5.4%) were positive; among them, 94.0% were classified into 5 subtypes (A1, A2a, A2b, B1, and B2). Some clinical manifestations differed according to hMPV genotype; however, there was no correlation between hMPV subtype and clinical outcome. Viral activity peaked at 13–20 weeks (April and May) and was associated with climate-specific factors, including temperature, relative humidity, diurnal temperature variation, wind speed, and sunshine duration. Conclusions This large-scale, 10-year study provides valuable information about the clinical characteristics associated with hMPV subtypes and climate factors contributing to virus transmission.

scholarly journals Cell-Mediated Responses to Human Metapneumovirus Infection

Viruses ◽  
2020 ◽  
Vol 12 (5) ◽  
pp. 542
Author(s):  
Marlies Ballegeer ◽  
Xavier Saelens
Keyword(s):  
Immune Response ◽  
Rna Virus ◽  
Cell Types ◽  
Host Immune Response ◽  
Human Metapneumovirus ◽  
Comprehensive Overview ◽  
Hmpv Infection ◽  
Life Threatening ◽  
Tract Infections ◽  
Almost All

Viruses are the most common cause of acute respiratory tract infections (ARTI). Human metapneumovirus (hMPV) frequently causes viral pneumonia which can become life-threatening if the virus spreads to the lungs. Even though hMPV was only isolated in 2001, this negative-stranded RNA virus has probably been circulating in the human population for many decades. Interestingly, almost all adults have serologic evidence of hMPV infection. A well-established host immune response is evoked when hMPV infection occurs. However, the virus has evolved to circumvent and even exploit the host immune response. Further, infection with hMPV induces a weak memory response, and re-infections during life are common. In this review, we provide a comprehensive overview of the different cell types involved in the immune response in order to better understand the immunopathology induced by hMPV. Such knowledge may contribute to the development of vaccines and therapeutics directed against hMPV.

scholarly journals Human Metapneumovirus Establishes Persistent Infection in Lung Microvascular Endothelial Cells and Primes a Th2-Skewed Immune Response

2020 ◽  
Vol 8 (6) ◽  
pp. 824
Author(s):  
Antonella Bugatti ◽  
Stefania Marsico ◽  
Manuela Fogli ◽  
Sara Roversi ◽  
Serena Messali ◽  
...  
Keyword(s):  
Immune Response ◽  
Endothelial Cells ◽  
Human Metapneumovirus ◽  
Size Exclusion ◽  
Microvascular Endothelial Cells ◽  
Cytopathic Effects ◽  
Viral Particles ◽  
Hmpv Infection ◽  
Microvascular Endothelial ◽  
Tract Infections

Human Metapneumovirus (HMPV) is a major cause of lower respiratory tract infections. HMPV infection has been hypothesized to alter dendritic cell (DC) immune response; however, many questions regarding HMPV pathogenesis within the infected lung remain unanswered. Here, we show that HMPV productively infects human lung microvascular endothelial cells (L-HMVECs). The release of infectious virus occurs for up to more than 30 days of culture without producing overt cytopathic effects and medium derived from persistently HMPV-infected L-HMVECs (secretome) induced monocyte-derived DCs to prime naïve CD4 T-cells toward a Th2 phenotype. Moreover, we demonstrated that infected secretomes trigger DCs to up-regulate OX40L expression and OX40L neutralization abolished the pro-Th2 effect that is induced by HMPV-secretome. We clarified secretome from HMPV by size exclusion and ultracentrifugation with the aim to characterize the role of viral particles in the observed pro-Th2 effect. In both cases, the percentage of IL-4-producing cells and expression of OX40L returned at basal levels. Finally, we showed that HMPV, per se, could reproduce the ability of secretome to prime pro-Th2 DCs. These results suggest that HMPV, persistently released by L-HMVECs, might take part in the development of a skewed, pro-Th2 lung microenvironment.

scholarly journals Cytotoxic T-Lymphocyte Epitope Vaccination Protects against Human Metapneumovirus Infection and Disease in Mice

2006 ◽  
Vol 80 (4) ◽  
pp. 2034-2044 ◽  
Author(s):  
Karen A. Herd ◽  
Suresh Mahalingam ◽  
Ian M. Mackay ◽  
Michael Nissen ◽  
Theo P. Sloots ◽  
...  
Keyword(s):  
Young Children ◽  
T Lymphocyte ◽  
Cytotoxic T Lymphocyte ◽  
Human Metapneumovirus ◽  
Respiratory Pathogen ◽  
Interleukin 12 ◽  
Ctl Epitopes ◽  
Ctl Epitope ◽  
Hmpv Infection ◽  
Tract Infections

ABSTRACT Human metapneumovirus (hMPV) has emerged as an important human respiratory pathogen causing upper and lower respiratory tract infections in young children and older adults. In addition, hMPV infection is associated with asthma exacerbation in young children. Recent epidemiological evidence indicates that hMPV may cocirculate with human respiratory syncytial virus (hRSV) and mediate clinical disease similar to that seen with hRSV. Therefore, a vaccine for hMPV is highly desirable. In the present study, we used predictive bioinformatics, peptide immunization, and functional T-cell assays to define hMPV cytotoxic T-lymphocyte (CTL) epitopes recognized by mouse T cells restricted through several major histocompatibility complex class I alleles, including HLA-A*0201. We demonstrate that peptide immunization with hMPV CTL epitopes reduces viral load and immunopathology in the lungs of hMPV-challenged mice and enhances the expression of Th1-type cytokines (gamma interferon and interleukin-12 [IL-12]) in lungs and regional lymph nodes. In addition, we show that levels of Th2-type cytokines (IL-10 and IL-4) are significantly lower in hMPV CTL epitope-vaccinated mice challenged with hMPV. These results demonstrate for the first time the efficacy of an hMPV CTL epitope vaccine in the control of hMPV infection in a murine model.

scholarly journals South Korea's Scramble for Africa: Complexities and Implications

2010 ◽  
Vol 11 (1) ◽  
pp. 55-72
Author(s):  
Mark Curry
Keyword(s):  
International Relations ◽  
South Korea ◽  
Large Scale ◽  
Historical Context ◽  
Food Resources ◽  
Limited Experience ◽  
History Of

South Korea had recently made agreements to secure large-scale deals in Tanzania, among other places, to secure cheap, long term agriculture supplies. Having limited experience in Africa, the potential for problems with Korea’s partners is great. The feasibility, desirability and legitimacy of such projects must be examined to forestall difficulties. Africa’s volatility and Tanzania’s complex historical context likewise need to be understood alongside Korea’s own history of colonization of Tanzanian indigenous people’s land. Also, Korea’s geopolitical standing and emergency as a developed county are implicated by such ventures. Significantly, securing future food resources by controlling large territories in distant continents is relevant to any discussion of Korea’s security and international relations.

Cluster analysis for dispersion patterns near nuclear power plants in South Korea

2020 ◽  
Author(s):  
Hyunha Lee ◽  
Chunsil Jin ◽  
Chunji Kim
Keyword(s):  
Power Plant ◽  
South Korea ◽  
Nuclear Power ◽  
Power Plants ◽  
Meteorological Data ◽  
Flow Patterns ◽  
Modeling Framework ◽  
Dispersion Patterns ◽  
The Impact

<p>  Clustering analysis using air parcel trajectories is actively used to investigate transport patterns of pollutants. To estimate the impact of nuclide dispersion from nuclear accident, comprehensive information based on long-term meteorological data is required to eatablish a complete and efficient public protection plan. Most of nuclear plants in South Korea are located in a complex terrain near coastal area that involves complicated meteorological phenomenon such as sea breezes and mountain-valley breezes. Robust approach based on long-term climatrological data is required to fully resolve the impacts near Korean nuclear power plants.</p><p>  In this study, we assessed the impacts of potential nuclear accident in South Korea by clustering dispersion patterns using 10-year meteorological data. Flow patterns are clustered using trajectory cluster analysis, and then combined with dispersion simulations to demonstrate the clustered dispersion patterns by each season and nuclear power plant.</p><p>  The long-term meteorological simulations from 2007 to 2016 were used to evaluate the potential impact of nuclear accidents in Korea, and the modeling framework was designed to show the impact map according to the flow patterns near each nuclear power plant. NOAA HYSPLIT modeling additional clustering analysis suggests that two or three cluster patterns for each power plant can be used. A total of 38 flow patterns are classified near the four nuclear plants in the previous season based on a 10-year wind field analysis. Korea has very complex terrain and coastal areas, and more sophisticated modeling efforts are needed to fully understand the more realistic dispersion characteristics of air masses. In terms of space-time resolution, updating land use information for simulation is very important for weather simulation near the surface of Korea.</p><p>  The results of this study can be used as a guideline for constructing a modeling framework for nuclide diffusion simulations, but given these complex simulation configurations, the results demonstrated in the current study are should be interpreted with caution.</p><p> </p>

scholarly journals Long-Term Spatiotemporal Variation and Environmental Driving Forces Analyses of Algal Blooms in Taihu Lake Based on Multi-Source Satellite and Land Observations

Water ◽  
2020 ◽  
Vol 12 (4) ◽  
pp. 1035
Author(s):  
Tiantian Zhang ◽  
Hong Hu ◽  
Xiaoshuang Ma ◽  
Yaobo Zhang
Keyword(s):  
Algal Blooms ◽  
Taihu Lake ◽  
Algal Bloom ◽  
Driving Forces ◽  
Sunshine Duration ◽  
Meteorological Data ◽  
Research Area ◽  
Lake Area ◽  
Variation Trends

The algal blooms caused by the eutrophication of lakes is a major environmental problem. In this study, we took China’s Taihu Lake as the research area, using multi-source satellite imagery data to monitor the information of algal blooms from 2008 to 2017. Following the analyses of the temporal and spatial variation trends of the blooms, water quality and meteorological data from land observation stations were employed to investigate the main environmental driving forces of the algal bloom outbreaks. The results show that, over the decade, the blooms with medium and higher hazard degrees mainly occurred in summer and autumn, and especially in autumn. From 2008 to 2016, the algal blooms outbreak degree was relatively stable, but, in 2017, it was severe, and the Northwest Lake area and the northern bays had heavier blooms than the other lake areas. From the analyses of the environmental driving forces, the variation trend of total nitrogen (TN) and total phosphorus (TP) concentrations in Taihu Lake from 2008 to 2017 was moderate, and the minimum concentrations of TN and TP both exceeded the threshold for algal bloom outbreaks. It was also found that the algal bloom area had notable correlations with the sunshine duration, wind speed and direction, precipitation, and air pressure. The research results of this paper will provide a theoretical basis for the scientific prediction of the occurrence of algal blooms in Taihu Lake.

scholarly journals Epidemiology and genotypic diversity of human metapneumovirus in paediatric patients with acute respiratory infection in Beijing, China

2021 ◽  
Vol 18 (1) ◽  
Author(s):  
Chao Wang ◽  
Tianli Wei ◽  
Fenlian Ma ◽  
Hao Wang ◽  
Jianqiang Guo ◽  
...  
Keyword(s):  
Genotypic Diversity ◽  
Human Metapneumovirus ◽  
N Gene ◽  
Whole Genome ◽  
Epidemic Season ◽  
Viral Loads ◽  
Paediatric Patients ◽  
Hmpv Infection ◽  
Tract Infections ◽  
Beijing China

Abstract Background Acute respiratory tract infections (ARTIs) causes high amounts of morbidity and mortality worldwide every year. Human metapneumovirus (HMPV) is a major pathogen of ARTIs in children. In this study, we aimed to investigate the epidemiology and genotypic diversity of HMPV in children hospitalized with ARTIs in Beijing, China. Methods Hospitalized children aged < 14 years with ARTIs were enrolled from April 2017 to March 2018; nasopharyngeal aspirates were collected and subjected to real-time polymerase chain reaction tests for HMPV. HMPV-positive samples were genotyped based on a partial N gene. Whole genome sequences were determined for samples with high viral loads. Results 4.08% (52/1276) enrolled paediatric patients were identified as having HMPV infection. The epidemic season is winter and early spring, children aged ≤ 4 years were more susceptible to HMPV infection (47/52, 90.38%). The co-infection rate were 36.54% (19/52), the most common co-infected virus were influenza and respiratory syncytial virus. The main diagnoses of HMPV infection were pneumonia (29/52, 55.77%) and bronchitis (23/52, 44.23%), while the main clinical manifestations were cough, fever, rhinorrhoea, and sneeze. Among 48 HMPV-positive specimens, A2b (19/48, 39.58%) and B1 (26/48, 54.17%) were the main epidemic subtypes. Patients with HMPV genotype A infection had a higher viral load compared to genotype B patients (6.07 vs. 5.37 log10 RNA copies/ml). Five complete sequences of HMPV were obtained. This is the first report of a whole genome sequence of HMPV-B1 isolated in China. Conclusions HMPV is an important respiratory pathogen in paediatric patients. Cases of HMPV infection could burden hospitals in the epidemic season. HMPV viral loads and genotypes have no correlation with co-infection or clinical characteristics.

Sign in / Sign up

Export Citation Format

Share Document