Large-Scale Comparative Analyses of Tick Genomes Elucidate Their Genetic Diversity and Vector Capacities.

Among arthropod vectors, ticks transmit the most diverse human and animal pathogens, leading to an increasing number of new challenges worldwide. Here we sequenced and assembled high-quality genomes of six ixodid tick species and further resequenced 678 tick specimens to understand three key aspects of ticks: genetic diversity, population structure, and pathogen distribution. We explored the genetic basis common to ticks, including heme and hemoglobin digestion, iron metabolism, and reactive oxygen species, and unveiled for the first time that genetic structure and pathogen composition in different tick species are mainly shaped by ecological and geographic factors. We further identified species-specific determinants associated with different host ranges, life cycles, and distributions. The findings of this study are an invaluable resource for research and control of ticks and tick-borne diseases.

Spatial-temporal drivers and incidence heterogeneity of hemorrhagic fever with renal syndrome transmission in Shandong Province, China, 2016-2022.

BACKGROUND: Hemorrhagic fever with renal syndrome (HFRS) signals a recurring risk in Eurasia in recent years owing to its continued rise in case notifications and the extension of geographical distribution. This study was undertaken to investigate the spatiotemporal drivers and incidence heterogeneity of HFRS transmission in Shandong Province. METHODS: The epidemiological data for HFRS, meteorological data and socioeconomic data were obtained from China Information System for Disease Control and Prevention, China Meteorological Data Sharing Service System, and Shandong Statistical Yearbook, respectively. The spatial-temporal multicomponent model was employed to analyze the values of spatial-temporal components and the heterogeneity of HFRS transmission across distinct regions. RESULTS: The total effect values of the autoregressive, epidemic, and endemic components were 0.451, 0.187, and 0.033, respectively, exhibiting significant heterogeneity across various cities. This suggested a pivotal role of the autoregressive component in propelling HFRS transmission in Shandong Province. The epidemic component of Qingdao, Weifang, Yantai, Weihai, and Jining declined sharply at the onset of 2020. The random effect identified distinct incidence levels associated with Qingdao and Weifang, signifying regional variations in HFRS occurrence. CONCLUSIONS: The autoregressive component emerged as a significant driver in the transmission of HFRS in Shandong Province. Targeted preventive measures should be strategically implemented across various regions, taking into account the predominant component influencing the epidemic.

Strategies to inTerrupt RAbies Transmission for the Elimination Goal by 2030 In China (STRATEGIC): a modelling study.

BACKGROUND: A global plan has been set to end human deaths from dog-mediated rabies by 2030 ("Zero-by-30"), but whether it could be achieved in some countries, such as China, remains unclear. Although elimination strategies through post-exposure prophylaxis (PEP) use, dog vaccination, and patient risk assessments with integrated bite case management (IBCM) were proposed to be cost-effective, evidence is still lacking in China. We aim to evaluate the future burdens of dog-mediated human rabies deaths in the next decade and provide quantitative evidence on the cost-effectiveness of different rabies-control strategies in China. METHODS: Based on data from China's national human rabies surveillance system, we used decision-analytic modelling to estimate dog-mediated human rabies death trends in China till 2035. We simulated and compared the expected consequences and costs of different combination strategies of the status quo, improved access to PEP, mass dog vaccination, and use of IBCM. RESULTS: The predicted human rabies deaths in 2030 in China will be 308 (95%UI: 214-411) and remain stable in the next decade under the status quo. The strategy of improved PEP access alone could only decrease deaths to 212 (95%UI: 147-284) in 2028, remaining unchanged till 2035. In contrast, scaling up dog vaccination to coverage of 70% could eliminate rabies deaths by 2033 and prevent approximately 3,265 (95%UI: 2,477-3,687) extra deaths compared to the status quo during 2024-2035. Moreover, with the addition of IBCM, the "One Health" approach through mass dog vaccination could avoid unnecessary PEP use and substantially reduce total cost from 12.53 (95%UI: 11.71-13.34) to 8.73 (95%UI: 8.09-9.85) billion US dollars. Even if increasing the total costs of IBCM from 100 thousand to 652.10 million US dollars during 2024-2035, the combined strategy of mass dog vaccination and use of IBCM will still dominate, suggesting the robustness of our results. CONCLUSIONS: The combined strategy of mass dog vaccination and IBCM requires collaboration between health and livestock/veterinary sectors, and it could eliminate Chinese rabies deaths as early as 2033, with more deaths averted and less cost, indicating that adding IBCM could reduce unnecessary use of PEP and make the "One Health" rabies-control strategy most cost-effective.

Epidemiological characteristics and spatio-temporal analysis of brucellosis in Shandong province, 2015-2021.

BACKGROUND: Brucellosis is one of the major public health problems in China, it not only causes huge economic losses to the society, but also threatens the human's physical and mental health. The reported cases of brucellosis in Shandong province were at a high level, therefore, it is necessary for us to understand the epidemic characteristics and distribution trend of Brucellosis in Shandong province. This study aims to describe the epidemiological characteristics and spatial clustering characteristics of brucellosis in Shandong Province, provide a reference for the scientific prevention and control. METHODS: Human brucellosis data in Shandong province from 2015 to 2021 were obtained from the China Information System for Disease Control and Prevention, the data were analyzed by descriptive epidemiological methods, spatial autocorrelation analysis and spatial-temporal cluster analysis methods use ArcGIS and SaTScan software, the results were presented in ArcMap. RESULTS: A total of 22,251 human cases of brucellosis were reported, the annual incidence ranged between 2.41/100,000 and 4.07/100,000 from 2015 to 2021 in Shandong province, incidence has been decreasing year by year, while there was a significant increase in 2021. The distribution of brucellosis was of a seasonal trend, mainly concentrating during March to August. The age of the cases was mainly concentrated in the 30-74 age ranges, the average annual incidence rate was significantly higher in males than in females. The spatial analysis showed that the epidemics were mainly concentrated in the north and southwest. For the spatial autocorrelation analysis, a high global autocorrelation was observed at the county level, and the high-high clusters mainly distributed in the north and southwest region. For the spatio-temporal scanning, the most likely cluster areas mainly distributed in the north area, and then gradually moved southward, and the radius of clustered narrowed. CONCLUSIONS: Human brucellosis remains a common challenge, particularly in northern region in spring and summer. More disease prevention and control measures should be taken in high-risk populations, and such higher-risk susceptible areas to reduce the incidence of brucellosis and ensure the health of the people.

Spatiotemporal distribution and environmental influences of severe fever with thrombocytopenia syndrome in Shandong Province, China.

BACKGROUND: Severe fever with thrombocytopenia syndrome (SFTS) is an emerging infectious disease discovered in China in 2009. The purpose of this study was to describe the spatiotemporal distribution of SFTS and to identify its environmental influencing factors and potential high-risk areas in Shandong Province, China. METHODS: Data on the SFTS incidence from 2010 to 2021 were collected. Spatiotemporal scan statistics were used to identify the time and area of SFTS clustering. The maximum entropy (MaxEnt) model was used to analyse environmental influences and predict high-risk areas. RESULTS: From 2010 to 2021, a total of 5705 cases of SFTS were reported in Shandong. The number of SFTS cases increased yearly, with a peak incidence from April to October each year. Spatiotemporal scan statistics showed the existence of one most likely cluster and two secondary likely clusters in Shandong. The most likely cluster was in the eastern region, from May to October 2021. The first secondary cluster was in the central region, from May to October 2021. The second secondary cluster was in the southeastern region, from May to September 2020. The MaxEnt model showed that the mean annual wind speed, NDVI, cattle density and annual cumulative precipitation were the key factors influencing the occurrence of SFTS. The predicted risk map showed that the area of high prevalence was 28,120 km2, accounting for 18.05% of the total area of the province. CONCLUSIONS: The spatiotemporal distribution of SFTS was heterogeneous and influenced by multidimensional environmental factors. This should be considered as a basis for delineating SFTS risk areas and developing SFTS prevention and control measures.

High-Throughput Method for Natural Organic Matter Hydrophobicity Assessment Using an Ionic Liquid-Based Aqueous Two-Phase System.

Hydrophobicity of natural organic matter (NOM) is one of its fundamental properties that influence the environmental fate of pollutants and the performance of many water treatment unit processes. In this study, a high-throughput method was developed for NOM hydrophobicity measurement based on the phase separation technique in the 96-well format. It measures the partition coefficients of NOM (KATPS,IL) in an ionic liquid (IL)-based aqueous two-phase system (ATPS). The ATPS was made of 1-butyl-3-methylimidazole bromide solution and a salt solution containing potassium phosphate monobasic and potassium phosphate dibasic. The partition of NOM in IL-based ATPS is mainly affected by its hydrophobicity. log KATPS,IL linearly correlated with the commonly used NOM hydrophobicity scales, including (O + N)/C, O/C, and aromatic carbons. KATPS,IL provided a more accurate assessment of NOM hydrophobicity than spectroscopic indices. Furthermore, KATPS,IL can predict the organic carbon-water partition coefficients for hydrophobic organic chemical sorption to NOM based on the two-phase system model. The high-throughput KATPS,IL measurement and the two-phase system model can be applied to real surface water samples. Our results suggest that the proposed high-throughput method has great potential to be applied to monitor NOM hydrophobicity for environmental risk assessment and water treatment purposes.

Detection of SFTS virus RNA and antibodies in severe fever with thrombocytopenia syndrome surveillance cases in endemic areas of China.

BACKGROUND: Severe fever with thrombocytopenia syndrome (SFTS) is a newly identified severe infectious disease caused by SFTS phlebovirus (SFTSV). SFTS monitoring has been carried out since 2010 in mainland China. We analysed the detection results of SFTSV RNA and antibody in SFTS surveillance cases to provide basic data for SFTS diagnosis. METHODS: This study was conducted in Shandong Province. Sera of SFTS surveillance cases were collected to detect SFTSV RNA and antibody by real-time RT-PCR and enzyme-linked immunosorbent assay, respectively. Detection rates were calculated. SPSS 18.0 (Chicago, IL, USA) was used for statistical analysis to compare the detection rates of SFTSV RNA and antibodies among different sera groups. RESULTS: A total of 374 SFTS surveillance cases were enrolled. Overall, 93.3% (349/374) of the sera samples were collected within 2 weeks after onset, and 6.7% (25/374) were collected between 15 days and 45 days. Of these, 183 (48.9%) were positive for SFTSV RNA. The SFTSV RNA-positive rate peaked (52.2%) in samples collected ≤7 days after onset and then showed a decreasing trend. The detection rate of SFTSV-specific IgM antibody was 30.5% (46/151) and was highest in samples collected between 8 and 14 days (43.3%, 26/60). The positive rate of SFTSV-specific IgG antibody (17.9%, 27/151) showed an increasing trend with the specimen collection time. In total, 74.8% (113/151) of sera samples had the same SFTSV RNA and IgM antibody detection results. However, 23.2% (29/125) of SFTSV RNA-negative cases were IgM antibody-positive, and 8.6% (9/105) of IgM antibody-negative cases were SFTSV RNA-positive. CONCLUSIONS: SFTSV RNA detection was preferred for SFTSV infection during disease surveillance. For highly suspected SFTS cases, IgM antibody is suggested to make a comprehensive judgement.

A Neonatal Murine Model of Coxsackievirus A6 Infection for Evaluation of Antiviral and Vaccine Efficacy.

Hand, foot, and mouth disease (HFMD) is a global health concern. Family Picornaviridae members, particularly enterovirus A71 (EVA71) and coxsackievirus A16 (CVA16), are the primary etiological agents of HFMD; however, a third enterovirus A species, CVA6, has been recently associated with epidemic outbreaks. Study of the pathogenesis of CVA6 infection and development of antivirals and vaccines are hindered by a lack of appropriate animal models. We have developed and characterized a murine model of CVA6 infection that was employed to evaluate the antiviral activities of different drugs and the protective efficacies of CVA6-inactivated vaccines. Neonatal mice were susceptible to CVA6 infection via intramuscular inoculation, and the susceptibility of mice to CVA6 infection was age and dose dependent. Five-day-old mice infected with 105.5 50% tissue culture infective doses of the CVA6 WF057R strain consistently exhibited clinical signs, including reduced mobility, lower weight gain, and quadriplegia with significant pathology in the brain, hind limb skeletal muscles, and lungs of the infected mice in the moribund state. Immunohistochemical analysis and quantitative reverse transcription-PCR (qRT-PCR) analyses showed high viral loads (11 log10/mg) in skeletal muscle, and elevated levels of interleukin-6 (IL-6; >2,000 pg/ml) were associated with severe viral pneumonia and encephalitis. Ribavirin and gamma interferon administered prophylactically diminished CVA6-associated pathology in vivo, and treatment with IL-6 accelerated the death of neonatal mice. Both specific anti-CVA6 serum and maternal antibody play important roles in controlling CVA6 infection and viral replication. Collectively, these findings indicate that this neonatal murine model will be invaluable in future studies to develop CVA6-specific antivirals and vaccines.IMPORTANCE Although coxsackievirus A6 (CVA6) infections are commonly mild and self-limiting, a small proportion of children may have serious complications, such as encephalitis, acute flaccid paralysis, and neurorespiratory syndrome, leading to fatalities. We have established a mouse model of CVA6 infection by inoculation of neonatal mice with a CVA6 clinical isolate that produced consistent pathological outcomes. Here, using this model of CVA6 infection, we found that high levels of IL-6 were associated with severe viral pneumonia and encephalitis, as in an evaluation of antiviral efficacy in vivo, IL-6 had no protective effect and instead accelerated death in neonatal mice. We demonstrated that, as antiviral drugs, both gamma interferon and ribavirin played important protective roles in the early stages of infection, with increased survival in treated neonatal mice challenged with CVA6. Moreover, active and passive immunization with the inactivated vaccines and anti-CVA6 serum also protected mice against homologous challenge infections.

Protective Efficacies of Formaldehyde-Inactivated Whole-Virus Vaccine and Antivirals in a Murine Model of Coxsackievirus A10 Infection.

Coxsackievirus A10 (CVA10) is one of the major pathogens associated with hand, foot, and mouth disease (HFMD). CVA10 infection can cause herpangina and viral pneumonia, which can be complicated by severe neurological sequelae. The morbidity and mortality of CVA10-associated HFMD have been increasing in recent years, particularly in the pan-Pacific region. There are limited studies, however, on the pathogenesis and immunology of CVA10-associated HFMD infections, and few antiviral drugs or vaccines have been reported. In the present study, a cell-adapted CVA10 strain was employed to inoculate intramuscularly 5-day-old ICR mice, which developed significant clinical signs, including reduced mobility, lower weight gain, and quadriplegia, with significant pathology in the brain, hind limb skeletal muscles, and lungs of infected mice in the moribund state. The severity of illness was associated with abnormally high expression of the proinflammatory cytokine interleukin 6 (IL-6). Antiviral assays demonstrated that ribavirin and gamma interferon administration could significantly inhibit CVA10 replication both in vitro and in vivo In addition, formaldehyde-inactivated CVA10 whole-virus vaccines induced immune responses in adult mice, and maternal neutralizing antibodies could be transmitted to neonatal mice, providing protection against CVA10 clinical strains. Furthermore, high-titer antisera were effective against CVA10 and could relieve early clinical symptoms and improve the survival rates of CVA10-challenged neonatal mice. In summary, we present a novel murine model to study CVA10 pathology that will be extremely useful in developing effective antivirals and vaccines to diminish the burden of HFMD-associated disease.IMPORTANCE Hand, foot, and mouth disease cases in infancy, arising from coxsackievirus A10 (CVA10) infections, are typically benign, resolving without any significant adverse events. Severe disease and fatalities, however, can occur in some children, necessitating the development of vaccines and antiviral therapies. The present study has established a newborn-mouse model of CVA10 that, importantly, recapitulates many aspects of human disease with respect to the neuropathology and skeletal muscle pathology. We found that high levels of the proinflammatory cytokine interleukin 6 correlated with disease severity and that ribavirin and gamma interferon could decrease viral titers in vitro and in vivo Whole-virus vaccines produced immune responses in adult mice, and immunized mothers conferred protection on neonates against challenge from CVA10 clinical strains. Passive immunization with high-titer antisera could also improve survival rates in newborn animals.

Haemaphysalis longicornis Ticks as Reservoir and Vector of Severe Fever with Thrombocytopenia Syndrome Virus in China.

Severe fever with thrombocytopenia syndrome (SFTS) is an emerging hemorrhagic fever in East Asia caused by SFTS virus (SFTSV), a newly discovered phlebovirus. The Haemaphysalis longicornis tick has been suspected to be the vector of SFTSV. To determine whether SFTSV can be transmitted among ticks, from ticks to animals, and from animals to ticks, we conducted transmission studies between developmental stages of H. longicornis ticks and between ticks and mice. Using reverse transcription PCR, we also analyzed the prevalence of SFTSV infection among H. longicornis ticks collected from vegetation in Shandong Province, China. Our results showed a low prevalence of SFTSV among collected ticks (0.2%, 8/3,300 ticks), and we showed that ticks fed on SFTSV-infected mice could acquire the virus and transstadially and transovarially transmit it to other developmental stages of ticks. Furthermore, SFTSV-infected ticks could transmit the virus to mice during feeding. Our findings indicate ticks could serve as a vector and reservoir of SFTSV.

[Epidemiological investigation of predominance tick and the infectious status of severe fever thrombocytopenia syndrome virus in Penglai and Laizhou counties, Shandong province].

OBJECTIVE: To investigate the predominance ticks and the infectious status of severe fever with thrombocytopenia (SFTSV) in Penglai and Laizhou counties, Shandong province. METHODS: Two towns with high incidence rate were selected in Penglai and Laizhou, respectively, then three villages were selected in each towns. Parasitic ticks were collected from the host skin by hand manually and free ticks manually with white cloth from the grassland, monthly, during April to December in 2011. Samples were classified by original, varieties, developmental stages, then extracted RNA, using Realtime RT-PCR to test severe fever thrombocytopenia syndrome virus, S fragments were amplified with nested PCR, then isolated virus. By neighbor joining method in the phylogenetic tree, the minimum infection rate (MIR) was used to represent the infection status of ticks in novel bunyavirus. RESULTS: A total of 3 145 ticks were collected totally from 5 categories, there were 3 048(96.92%) of Haemaphysalis longicornis, 73(2.32%) of Rhinpicephalus sanguineus, 10(0.32%) of microplus Boophilus, 9(0.29%) of Haemaphysalis campanulata, 5(0.16%) of Dermacentor sinicus, respectively. The positive rate of nucleic acid of 2 044 samples was 6.16% (126/2 044), minimum infection rate (MIR) was 4.01%, there were 122(96.83%) of Haemaphysalis longicornis, 3(2.38%) of Rhinpicephalus sanguineus, and 1(0.79%) of microplus Boophilus, MIR was 4.00%, 4.11%, and 10.00%, respectively. There were no nucleic acid positive samples in Haemaphysalis campanulata and Dermacentor sinicus. The 11 S segments were amplified in 126 positive samples, the homology of S fragment was 95.6%-99.9% with 11 strains isolated from the identified SFTS cases in local area, 3 strains isolated from animals, and 11 strains isolated from other areas. There was no significant difference among original, varieties and developmental stages. CONCLUSION: Haemaphysalis longicornis was the predominant species in Penglai and Laizhou counties, it could be propagation medium with Rhipicephalus sanguineus and microplus Boophilus, S sequence in ticks was higher homology with virus isolated from local SFTS cases.

Association of functional polymorphisms in the MxA gene with susceptibility to enterovirus 71 infection.

Myxovirus resistance A (MxA) is an antiviral protein induced by type I interferons α and ß (IFN-α and IFN-ß) that can inhibit virus replication. We examined whether the MxA polymorphisms were related to the risk and severity of enterovirus 71 (EV71) infection in Chinese populations. The MxA C-123A and G-88T polymorphisms were genotyped in two independent case-control populations in China by polymerase chain reaction-based restriction fragment length polymorphism (PCR-RFLP) analysis. Multivariate logistic regression analysis was used to calculate adjusted odds ratios (ORs) and 95% confidence intervals (95% CIs). MxA messenger RNA was quantified by real-time quantitative PCR in peripheral blood mononuclear cells (PBMCs) from 45 healthy children and 19 patients with EV71 infection. Significantly decreased susceptibility to EV71 infection was observed for the -123A allele and -88T allele carriers, with ORs (95% CIs) estimated as 0.56 (0.39-0.81) and 0.64 (0.47-0.88), respectively, in the northern population. This association was confirmed in the southern population, with ORs (95% CIs) estimated as 0.58 (0.38-0.89) and 0.67(0.47-0.95), respectively. The A- 123T- 88 haplotype was also significantly associated with lower risk of EV71 infection in both the northern (OR = 0.62; 95% CI = 0.44-0.85) and the southern population (OR = 0.63; 95% CI = 0.43-0.92). Furthermore, we observed higher MxA messenger RNA levels in IFNß1a-stimulated PBMCs from the -123A or -88T allele carriers compared with that from nocarriers. Our findings suggest that polymorphisms in the MxA promoter may play a role in mediating the susceptibility to EV71 infection in Chinese population.

One family cluster of avian influenza A(H7N9) virus infection in Shandong, China.

BACKGROUND: The first case of human infection with avian influenza A (H7N9) virus was identified in March, 2013 and the new H7N9 virus infected 134 patients and killed 45 people in China as of September 30, 2013. Family clusters with confirmed or suspected the new H7N9 virus infection were previously reported, but the family cluster of H7N9 virus infection in Shandong Province was first reported. CASE PRESENTATION: A 36-year-old man was admitted to Zaozhuang City Hospital with progressive respiratory distress and suspicion of impending acute respiratory distress syndrome on April 21. The chest radiography revealed bilateral ground-glass opacities and pulmonary lesions. The second case, the first case's 4 year old son, was admitted to the same hospital on April 28 with fever and multiple patchy shadows in the bilateral lungs. Both of the two cases were confirmed to infect with H7N9 virus by the results of real-time reverse transcriptase-polymerase-chain reaction (rRT-PCR), virus isolation and serum antibody titer. At the same time, one environment samples was detected positive for H7N9 virus in the living poultry market in Zaozhuang. The homologous analysis of the full genome sequence indicated that both viruses from the patients were almost genetically identical. The field epidemiology investigation showed that the two cases had no recognized exposure to poultry, but had the exposure to the environment. The second case had substantial unprotected close exposure to his ill father and developed symptoms seven days after his last contact with his father. After surgery, the index case and his son were discharged on May 16 and May 6, respectively. 11 close contacts of both patients were identified and tested negative both the throat swabs and the serum antibody. CONCLUSION: The infection of the index case probably resulted from contact with environmentally contaminated material. For the son, the probable infection source was from the index case during unprotected exposure, but the possibility from the environment or other sources could not be completely ruled out.

Molecular Epidemiological Study of a Human Brucellosis Outbreak - Weihai City, Shandong Province, China, 2022.

What is already known about this topic?: Brucellosis, mainly caused by Brucella melitensis (B. melitensis), is regarded as a significant zoonotic disease in China. In Weihai, located at the eastern end of the Shandong Peninsula, brucellosis has been in a low epidemic phase for the past five years. What is added by this report?: This was the initial report of a brucellosis outbreak in the last five years. Strains of B. melitensis bv. 3 from Weihai and other cities showed a close genetic relationship, suggesting a potential common ancestry. What are the implications for public health practice?: Epidemiological investigations depend on standardized and effective molecular typing methods and analysis tools for public health laboratories to identify and trace outbreaks. Understanding the circulation patterns of livestock in free-range households in heavily affected areas is essential for controlling the spread of brucellosis.

Changes in Cytokine Levels in Patients with Severe Fever with Thrombocytopenia Syndrome Virus.

Purpose: To characterize the cytokine profile of patients with severe fever with thrombocytopenia syndrome (SFTS) in relation to disease severity. Patients and Methods: 60 laboratory-confirmed SFTS patients and 12 healthy individuals from multi-centers in Shandong Province of China were included, and all patients were divided into fatal patients (9) and recovered patients (51) due to their final outcomes. Multiplex-microbead immunoassays were conducted to estimate levels of 27 cytokines in the sera of patients and controls. Results: The results showed that levels of IL-2, IL-4, IL-6, IL-7, IL-8, IL-15, IL-1RA, G-CSF, GM-CSF, IFN-γ, TNF-α, basic FGF, PDGF-BB, RANTES, IP-10, MIP-1α, MIP-1ß, MCP-1, and Eotaxin differed significantly among the SFTS fatal patients, recovered patients, and the healthy controls (all p<0.05). Compared to the healthy controls, the fatal patients and recovered patients had reduced levels of IL-2, IL-4, IL-7, PDGF-BB, RANTES, and Eotaxin, while the levels of PDGF-BB and RANTES were significantly lower in fatal patients compared to recovered patients. The increasing levels of IL-6, IL-8, IL-15, IL-1RA, G-CSF, GM-CSF, IFN-γ, TNF-α, basic FGF, IP-10, MIP-1α, MIP-1ß, and MCP-1 were observed in fatal patients (all p<0.05), and the levels of IL-6, IP-10, MIP-1α, and MCP-1 were significantly higher than other two groups. The Spearman correlation analysis indicated a positive correlation between platelet count and PDGF-BB levels (p<0.05), while the white blood cell count had a negative correlation with MIP-1 level (p<0.05). Conclusion: The research exhibited that the SFTS virus (SFTSV) caused an atypical manifestation of cytokines. The levels of IL-6, IP-10, MIP-1α, and MCP-1 had been observed a positive association with the severity of the illness.

Virome diversity shaped by genetic evolution and ecological landscape of Haemaphysalis longicornis.

BACKGROUND: Haemaphysalis longicornis is drawing attentions for its geographic invasion, extending population, and emerging disease threat. However, there are still substantial gaps in our knowledge of viral composition in relation to genetic diversity of H. longicornis and ecological factors, which are important for us to understand interactions between virus and vector, as well as between vector and ecological elements. RESULTS: We conducted the meta-transcriptomic sequencing of 136 pools of H. longicornis and identified 508 RNA viruses of 48 viral species, 22 of which have never been reported. Phylogenetic analysis of mitochondrion sequences divided the ticks into two genetic clades, each of which was geographically clustered and significantly associated with ecological factors, including altitude, precipitation, and normalized difference vegetation index. The two clades showed significant difference in virome diversity and shared about one fifth number of viral species that might have evolved to "generalists." Notably, Bandavirus dabieense, the pathogen of severe fever with thrombocytopenia syndrome was only detected in ticks of clade 1, and half number of clade 2-specific viruses were aquatic-animal-associated. CONCLUSIONS: These findings highlight that the virome diversity is shaped by internal genetic evolution and external ecological landscape of H. longicornis and provide the new foundation for promoting the studies on virus-vector-ecology interaction and eventually for evaluating the risk of H. longicornis for transmitting the viruses to humans and animals. Video Abstract.

Genetic variants of Orientia tsutsugamushi in domestic rodents, northern China.

We screened Orientia tsutsugamushi from 385 domestic rodents and 19 humans with scrub typhus in rural Tai'an District, Shandong Province, a new scrub typhus epidemic area in northern China. Sequence analysis identified 7 genotypes in the rodents, of which 2 were also identified in the humans.

Severe fever with thrombocytopenia syndrome virus among domesticated animals, China.

To investigate the infections of severe fever with thrombocytopenia syndrome virus (SFTSV) in domesticated animals, we sampled a total of 3,039 animals in 2 counties in Shandong Province, People's Republic of China, from April to November 2011. SFTSV-specific antibodies were detected in 328 (69.5%) of 472 sheep, 509 (60.5%) of 842 cattle, 136 (37.9%) of 359 dogs, 26 (3.1%) of 839 pigs, and 250 (47.4%) of 527 chickens. SFTSV RNA was detected in all sampled animal species, but the prevalence was low, ranging from 1.7% to 5.3%. A cohort study in 38 sheep was conducted to determine when seroconversion to SFTSV occured. SFTSVs were isolated from sheep, cattle, and dogs and shared >95% sequence homology with human isolates from the same disease-endemic regions. These findings demonstrate that natural infections of SFTSV occur in several domesticated animal hosts in disease-endemic areas and that the virus has a wide host range.

Prevalence of enteroviruses in children with and without hand, foot, and mouth disease in China.

BACKGROUND: To determine the prevalence of human enteroviruses (HEVs) among healthy children, their parents, and children with hand, foot, and mouth disease (HFMD). METHODS: We conducted a case-control study that included throat samples from 579 children with HFMD and from 254 healthy controls. Throat samples from 49 households (98 parents and 53 healthy children) were also analyzed. Phylogenetic analysis was carried out to study genetic relationships of EV71 strains. RESULTS: The HEV positive rate in HFMD patients was significantly higher than that in healthy controls (76.0% vs. 23.2%, P < 0.001). The EV71 (43.7% vs. 15.0%, P < 0.001), CVA16 (18.0% vs. 2.8%, P < 0.001), and CVA10 (5.7% vs. 0.8%, P = 0.001) serotypes were significantly overrepresented in HFMD patients in comparison to healthy children. Other HEV serotypes were detected with comparable frequency in cases and controls. The HEV positive rate in severe HFMD patients was significantly higher than that in mild group (82.1% vs. 73.8%, P = 0.04). The EV71 (55.0% vs. 39.7%, P = 0.001) and CVA16 (11. 9% vs. 20.0%, P = 0.024) positive rate differed significantly between severe and mild HFMD patients. Other HEV serotypes were detected with comparable frequency between severe and mild HFMD patients. Among 49 households, 22 households (44.9%) had at least 1 family member positive for HEV. Children had significantly higher HEV positive rate than adult (28.3% vs. 14.3%, P = 0.037). The HEV positive rate was similar between mothers and fathers (12.24% vs. 16.32%, P = 0.56). The VP1 sequences of EV71 from HFMD patients and healthy children were nearly identical and all were clustered in the same clade, C4a. CONCLUSIONS: Our study demonstrated the co-circulation of multiple HEV serotypes in children with and without HFMD during epidemic. Our study deserves the attention on HFMD control.

[The infection status and epidemic rule of new bunia virus in the livestock and poultry in hilly area of Jiaodong peninsula].

OBJECTIVE: To understand the infection status and epidemic rule of new bunia virus in the livestock and poultry which are closely related with humans such as sheep, cattle, dogs, pigs and chicken in the hilly area of Jiaodong peninsula in Shandong province. METHODS: Penglai and Laizhou in the hilly area of Jiaodong peninsula in Shandong province where severe fever with thrombocytopenia syndrome cases occurred in 2010 were selected as experimental sites. During April to November in 2011, serum specimens of the sheep, cattle, dogs, pigs and chicken with ticks in endemic area were randomly collected by random number table.5 ml venous blood was collected in each livestocks or poultries and there were total 3576 samples.New bunia virus antibody in different species of livestocks or poultries serum was continuously detected using double antigen sandwich enzyme-linked immunosorbent assay, and the infection rates of new bunia virus between different species of livestocks or poultries and between Penglai and Laizhou were analyzed using chi-square test. RESULTS: Test results in 3576 samples of livestocks or poultries serum specimen showed that the infection rate was as high as 63% (636/1013) in sheep, 53% (444/841)in cattle, 46% (242/530) in chicken, 29% (104/362)in the dogs, and 1% (12/830) in pigs. There were significant differences of new bunia virus infection among different species (χ(2) = 815.26, P < 0.05).In Penglai, the infection rate was as high as 71% (400/563) in sheep, 57% (232/409)in cattle, 35% (93/266) in chicken, 44% (796/1819)in total, while in Laizhou, the infection rate was 53% (236/450)in sheep, 49% (212/432)in cattle, 56% (149/264)in chicken, 36% (642/1757)in total, their difference was statistically significant(χ(2) values were 37.04, 4.93, 24.63, 19.38, all P values were < 0.05).Infection rates of dogs and pigs showed no obvious fluctuation.However, there were two peaks of infection in sheep in summer and autumn, the infection rate was as high as 62% (68/110) in June and 86% (204/236) in November;There were two peaks of infection in cattle in spring and autumn, the infection rate was as high as 56% (53/94) in April and 73% (116/159) in November; there was only one peak of infection in chicken, the infection rate was as high as 65% (55/85) in September. CONCLUSION: The infection rate is higher in sheep, cattle, chickens and dogs in the hilly area of Jiaodong peninsula. The peak season is spring, summer and autumn.