Xian Qi

• Jiangsu Provincial Center for Disease Control and Prevention

Introduction: China implemented a dynamic zero-COVID strategy to curb viral transmission in response to the coronavirus disease 2019 (COVID-19) pandemic. This strategy was designed to inhibit mutation of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), the virus responsible for COVID-19. This study explores the dynamics of viral evolut...

Following two human infections with the H10N3 avian influenza virus (AIV) in 2021 and 2022, a third case was discovered in Yunnan, China, in 2024, raising concerns about the potential for future pandemics. Recent studies have indicated that novel H10N3 viruses are highly pathogenic in mice and can be transmitted between guinea pigs via respiratory...

Background Since 2020, global attention has heightened towards epidemics caused by avian influenza A H5N1 virus of clade 2.3.4.4b in birds and mammals. This study presents the epidemiological history, clinical manifestations, and prognosis of a unique case infected with avian influenza A H5N1 clade 2.3.4.4b, along with the continuation of SARS-CoV-...

Encephalitis or encephalopathy during severe fever with thrombocytopenia syndrome (SFTS) is considered a critical risk factor leading to high mortality, but there have been no studies to date on the pathogenesis of encephalitis or encephalopathy caused by SFTS virus. Here, we report that SFTSV infection can active the NLRP3 inflammasome and induce...

Zika virus (ZIKV) is a mosquito-borne flavivirus and can cause neurodevelopmental disorders in fetus. As a neurotropic virus, ZIKV persistently infects neural tissues during pregnancy but the viral pathogenesis remains largely unknown. ZIKV has a positive-sense and single-stranded RNA genome, which encodes 7 non-structural (NS) proteins, participat...

Within the local outbreak period of SARS-CoV-2 Delta variant in Nanjing and Yangzhou, China, we analyzed the mutation process of the Delta variants in 520 cases, as well as the production, spread and elimination of new mutant strains under the non-pharmaceutical interventions (NPI) strategy. The investigation on distribution of COVID-19 cases and p...

Zika virus (ZIKV) is a positive-sense RNA flavivirus and can cause serious neurological disorders including microcephaly in infected fetus. As a mosquito-borne arbovirus, ZIKV enters bloodstream and is transmitted into the fetus through the placenta in pregnant women. Monocytes are considered one of the earliest blood cell types to be infected by Z...

Apoptosis, pyroptosis and necroptosis are regulated processes of cell death which can be crucial for viral disease outcomes in hosts because of their effects on viral pathogenicity and host resistance. Zika virus (ZIKV) is a mosquito-borne flavivirus, which infects humans and can cause neurological disorders. Neural developmental disorders and micr...

During 2018, we conducted periodic bioaerosol sampling at a live bird market in Kunshan China and found (55%) of 120 samples to have evidence of avian influenza virus. We recovered four live viruses through egg culture. These results support the effectiveness of noninvasive bioaerosol sampling in live animal markets.

Avian influenza A(H5N6) keeps evolving, causing outbreaks in birds and sporadic infections in human. Here we report a fatal pediatric infection caused by a novel reassortant H5N6 virus. The patient was an obese 9‐year‐old girl. She initiated with fever and cough, then developed pneumonia, acute respiratory distress syndrome (ARDS) and respiratory f...

Induction of type I IFNs during viral infection is crucial for host defense. IRF 3 and IRF7 play a critical role as key transcription factors in the activation of the IFN induction. Viruses have evolved a variety of strategies to evade innate immunity. Our previous studies have shown that the nonstructural protein (NSs) of the severe fever with thr...

Objective: We aimed to evaluate and quantify the association between ambient temperature and activity of influenza like illness (ILI) and influenza in Jiangsu Province, China. Method: Daily data of meteorology, influenza-like illness and detected influenza virus from 1 April 2013 to 27 March 2016 were collected. Distributed lag non-linear model...

Five epidemic waves of human infection with influenza A (H7N9) virus have emerged in China since spring 2013. We previously described the epidemiological characterization of the fifth wave in Jiangsu province. In this study, 41 H7N9 viruses from patients and live-poultry markets were isolated and sequenced to further elucidate the genetic features...

Human infections with influenza H7 subtypes, such as H7N9, have raised concerns worldwide. Here, we report a human infection with a novel influenza A(H7N4) virus. A 68 years-old woman with cardiovascular and cholecystic comorbidities developed rapidly progressed pneumonia with influenza-like-illness as initial symptom, recovered after 23 days-hospi...

Background A cluster of eleven patients, including eight family members and three healthcare workers with fever and thrombocytopenia occurred in Yixing County, Jiangsu Province, China, from October to November 1996. However, the initial investigation failed to identify its etiology. Severe fever with thrombocytopenia syndrome (SFTS) is an emerging...

Northern blot analysis of miR-HA-3p using total RNA derived from A549 cells infected with H5N1 virus (A/Anhui/2/2005) at 48 h post-infection.

Quantitative RT-PCR assay of TNF-α, IFN-β, IL-1β or IL-6 mRNA levels in human primary macrophages infected with H5N1 or mutant H5N1 viruses plus different treatments.

No effect of antagomir-HA-3p and various control antagomirs on viral replication.

Viral titers in mouse lungs after H5N1 or mutant H5N1 infection plus different treatments were determined by TCID50 assay using MDCK cells at different time points after infection.

Western blot analysis of protein levels of Dicer (A), Drosha (B) and Ago2 (C) aftertransfection of A549 cells with control or three different synthetic siRNAs at 48 h post-transfection.

Downregulation of PCBP2 expression in primary macrophages by miR-HA-3p.

The effect of mutations on viral replication in vitro.

No effect of antagomir-HA-3p and various control antagomirs on cytokines secretion in H5N1-infected macrophages.

The levels of miR-HA-3p detected by quantitative RT-PCR in lung and serum samples of mice infected with H5N1 or mutant H5N1 viruses on day 2 and day 4 post-infection.

Severe fever with thrombocytopenia syndrome (SFTS) is a novel tick-borne viral disease with high mortality. Since January 2010, we have conducted an epidemiological surveillance and etiological study of SFTS in Jiangsu and Anhui provinces. From January 2010 through December 2015, a total of 286 SFTS cases were confirmed in Jiangsu and Anhui provinc...

Metagenomic analysis through high-throughput sequencing is a tool for detecting both known and novel viruses. Using this technique, a novel circular single-stranded DNA (ssDNA) virus genome was discovered in respiratory secretions from a febrile traveler. The virus, named human respiratory-associated PSCV-5-like virus (HRAPLV), has a genome compris...

Background: Four epidemic waves of human infection with H7N9 have been recorded in China up to 1 June 2016, including in Jiangsu Province. However, few studies have investigated the differences in patients' characteristics among the 4 epidemic waves, and the analyses of factors associated with fatal infection lacked statistical power in previous s...

Background We aimed to determine the risk conferred by metabolic syndrome (METS) and diabetes mellitus (DM) to recurrent stroke in patients with minor ischemic stroke or transient ischemic attack from the CHANCE (Clopidogrel in High‐risk patients with Acute Non‐disabling Cerebrovascular Events) trial. Methods and Results In total, 3044 patients we...

Since first identified in 2013, the H7N9 virus has caused several waves of human infections in China, with a current wave including a number of patients with very severe disease. Jiangsu is one of the most impacted provinces, whereby as of 31 January 2017, the number of human infections (n = 109) in the ongoing fifth H7N9 wave has exceeded the sum...

Considering the fatal human victims and economic loss caused by influenza virus infection every year, methodologies for rapid and on-site detection of influenza viruses are urgently needed. LAMP is the most commonly used nucleic acid isothermal amplification technology suitable for on-site use. However, for multiplex LAMP, differentiation of the am...

BackgroundH7N9 continues to cause human infections and remains a pandemic concern. Understanding the economic impacts of this novel disease is important for making decisions on health resource allocation, including infectious disease prevention and control investment. However, there are limited data on such impacts. Methods Hospitalized laboratory-...

Synaptogyrin-2 is a non-neuronal member of the synaptogyrin family involved in synaptic vesicle biogenesis and trafficking. Little has been known about the function of synaptogyrin-2. Severe fever with thrombocytopenia syndrome (SFTS) is an emerging infectious disease characterized by high fever, thrombocytopenia, and leukocytopenia with high morta...

Severe fever with thrombocytopenia syndrome (SFTS) is an emerging infectious disease, which is caused by SFTS virus (SFTSV), a novel bunyavirus transmitted by ticks from animals. The disease is characterized by high fever and drastic reduction of leukocytes and platelets with high mortality rates in severe cases. We have reported that SFTSV suppres...

Synaptogyrin-2 is a non-neuronal member of the synaptogyrin family involved in synaptic vesicle biogenesis and trafficking. Little has been known about the function of synaptogyrin-2. Severe Fever with Thrombocytopenia Syndrome (SFTS) is an emerging infectious disease characterized by high fever, thrombocytopenia, and leukocytopenia with a high fat...

Severe fever with thrombocytopenia syndrome (SFTS) is caused by SFTS virus (SFTSV), a tick-borne phlebovirus in family Bunyaviridae. Studies have found that humans, domestic and wildlife animals can be infected by SFTSV. However, the viral ecology, circulation, and transmission remain largely unknown.Sixty seven human SFTS cases were reported and c...

Sequences of Isolated SFTSV Strains with Associated Location of Origin, Collection Dates, Host and GenBank Accession Numbers. (DOCX)

Detection of SFTSV RNA in Various Stages of Haemaphysalis concinna and Haemaphysalis doenitzi Ticks Collected from Vegetation and Wild Animals in 2013–2014 in Jiangsu. *MIR: Minimum infection rate, based on the formula: Number of positive pools/total number of ticks tested. Male: Male adult ticks; Female: Female adult ticks. (DOCX)

Since March 2013, more than 500 laboratory-confirmed human H7N9 influenza A virus infection cases have been recorded, with a case-fatality rate of more than 30%. Clinical research has shown that cytokine and chemokine dysregulation contributes to the pathogenicity of the H7N9 virus. Here, we investigated cytokine profiles in primary human macrophag...

Noroviruses (NoVs) are the most common cause of acute gastroenteritis in both sporadic and outbreak cases. Genotyping and recombination analyses were performed in order to help getting more knowledge of the distribution and genetic diversity of NoVs in Suzhou, located in Jiangsu province of China. All stool samples were collected from hospitalized...

Severe fever with thrombocytopenia syndrome virus (SFTSV), the causative agent for the fatal life-threatening infectious disease, severe fever with thrombocytopenia syndrome (SFTS), was first identified in the central and eastern regions of China. Although the viral RNA was detected in free-living and parasitic ticks, the vector for SFTSV remains u...

From September 2014 to March 2015, 23 outbreaks of norovirus (NoV) acute gastroenteritis occurred in Jiangsu, China. Partial sequencing of the NoV capsid gene suggested that 16 of the 23 outbreaks were related to a new GII.17 variant. This variant was first detected in sporadic specimens in October 2014, and became predominant in February 2015. Ana...

Influenza H7N9 and H1N1pdm can cause severe human infections. It is important to investigate the distinguishing clinical features between these two diseases. Several studies have compared the differences in general, however, age and gender adjusted comparisons may be more useful and informative to the health professionals. A total of 184 severe H1N...

In early 2013, a Bengal tiger (Panthera tigris) in a zoo died of respiratory distress. All specimens from the tiger were positive for HPAI H5N1, which were detected by real-time PCR, including nose swab, throat swab, tracheal swab, heart, liver, spleen, lung, kidney, aquae pericardii and cerebrospinal fluid. One stain of virus, A/Tiger/JS/1/2013, w...

Influenza A viruses (IAVs), particularly H1N1, H5N1 and H7N9, pose a substantial threat to public health worldwide. Here, we report that MIR2911, a honeysuckle (HS)-encoded atypical microRNA, directly targets IAVs with a broad spectrum. MIR2911 is highly stable in HS decoction, and continuous drinking or gavage feeding of HS decoction leads to a si...

The genome sequence of the strain A/chicken/Changzhou/C08/2013 (H9N9) shows that the hemagglutinin (HA) genes of this strain are closely related to those of the strain A/chicken/Shanghai/1107/2013 (H9N2) and share 99.2% nucleotide homology, while the other seven genes had the greatest sequence identities with the novel H7N9 virus. We speculate that...

An avian influenza virus, A/environment/Zhenjiang/C13/2013(H5N6), was isolated from a live poultry market in eastern China. Phylogenetic analysis showed that the isolate was a novel reassortant virus with a neuraminidase (NA) gene from H6N6 viruses and the other seven genes from H5N1 viruses, which may pose a potential threat to human and animal he...

An outbreak of anthrax was reported in Lianyungang, Jiangsu Province, China in 2012. Laboratory confirmation of cases was made by detection of Bacillus anthracis genes rpoB, pagA, and cap using real-time polymerase chain reaction (PCR); source tracking was conducted by multiple locus variable-number tandem-repeat analysis (MLVA) and pagA sequencing...

Noroviruses (NoVs) are the principal cause of epidemic viral gastroenteritis worldwide, including industrialized and developing countries. Eight hundred and fifty sporadic specimens from hospitalized children with acute gastroenteritis and 131 specimens from seven gastroenteritis outbreaks were collected during 2011-2012 in Jiangsu, China. All spec...

A novel avian influenza A(H7N9) virus causing human infection emerged in February 2013 in China. To elucidate the mechanism of interspecies transmission, we compared the signature amino acids of avian influenza A(H7N9) viruses from human and non-human hosts and analysed the reassortants of 146 influenza A(H7N9) viruses with full genome sequences. W...

Objective: To establish a rapid eukaryotic expression system of hemagglutinin (HA) gene of novel avian influenza H7N9 using lentiviral vector, express the recombinant protein and study its functions in human embryonic kidney HEK293T cells. Methods: The full-length HA gene was amplified from H7N9 genomic RNA by reverse transcription PCR (RT-PCR)...

Severe fever with thrombocytopenia syndrome (SFTS) is an emerging febrile illness caused by a novel phlebovirus in the family Bunyaviridae. We have previously shown that innate immunity in host cells was modulated in infected cells and antiviral cytokine induction was suppressed by nonstructural protein NSs of SFTSV. In this study, we analyzed the...

Severe fever with thrombocytopenia syndrome (SFTS) is an emerging febrile illness caused by a novel phlebovirus in the family Bunyaviridae. We have previously shown that innate immunity in host cells was modulated in infected cells and antiviral cytokine induction was suppressed by nonstructural protein NSs of SFTSV. In this study, we analyzed the...

Severe fever with thrombocytopenia syndrome (SFTS) is a newly identified viral zoonosis caused by a phlebovirus. Most reported SFTS cases are farmers living in rural areas. The seroprevalence of SFTS virus in farmers has not been investigated. The current knowledge of SFTS virus seroprevalence in animals, especially in wild animals, is still poor....

In 2007, the avian-like H1N1 virus (A/swine/Zhejiang/1/07) was first isolated in pigs in China. Recently, it was reported that a 3-year-old boy was infected with avian-like A (H1N1) swine influenza virus (SIV) in Jiangsu Province, China. To investigate the prevalence of avian-like A (H1N1) SIV infection among swine farm residents in eastern China,...

PB1-F2 protein has been proven to increase the pathogenicity of influenza A virus (IAV) strains in primary infection and in secondary bacterial infection. It can also regulate the activity of viral polymerase. However, it was shown in another retrospective study that a portion of IAVs do not express full-length PB1-F2 protein during virus developme...

Severe fever with thrombocytopenia syndrome (SFTS) virus is an emerging bunyavirus that causes a hemorrhagic fever with a high mortality rate. The virus is likely tick-borne and replicates primarily in hemopoietic cells, which may lead to disregulation of proinflammatory cytokine induction and loss of leukocytes and platelets. The viral genome cont...

A novel avian influenza A (H7N9) virus has caused great morbidity as well as mortality since its emergence in Eastern China in February 2013. However, the possible risk factors for death are not yet fully known. Patients with H7N9 virus infection between March 1 and August 14, 2013 in Jiangsu province were enrolled. Data were collected with a stand...

Cells are equipped with pattern recognition receptors (PRRs) such as the Toll-like and RIG-I-like receptors that mount innate defenses against viruses. However, viruses have evolved multiple strategies to evade or thwart host antiviral responses. Viral inclusion bodies (IBs), which are accumulated aggregates of viral proteins, are commonly formed d...

Influenza A (H7N9) virus has been causing human infections in China since February 2013, raising serious concerns of potential pandemics. Previous studies demonstrate that human infection is directly linked to live animal markets, and that the internal genes of the virus are derived from H9N2 viruses circulating in the Yangtze River Delta area in E...

During September 2010, an outbreak of acute hemorrhagic conjunctivitis reemerged in Jiangsu, three years after the nationwide epidemic in China in 2007. In total, 2409 cases were reported, 2118 of which were reported in September; 79.8% of those affected were students or teachers, with a median age of 16 years. To identify and demonstrate the genet...

To investigate the status of human bocavirus and to indentify its epidemiological characteristics as well as genotype distribution in patients with infantile viral diarrhea in Suzhou, Jiangsu province. 832 fecal specimens from patients with infantile virus diarrhea cases were collected from Suzhou Children's Hospital in 2010-2011. Human bocavirus w...

Descriptive and geographic information system methods were used to depict the spatial and temporal characteristics of the outbreak of human infection with a novel avian influenza A(H7N9) virus in mainland China, the peak of which appeared between 28 March and 18 April 2013. As of 31 May 2013, there was a total of 131 reported human infections in Ch...

Most recently a novel avian-origin influenza A (H7N9) virus emerged in China and has been associated with lots of human infection and fatal cases. Genetic analysis of the viral genome revealed that this reassortant virus might be better adapted to humans than other avian influenza viruses. Molecular diagnostic methods are thus urgently needed in pu...

A novel reassortant avian influenza A virus (H7N9) emerged in humans in Eastern China in late February, 2013. All virus strains were resistant to adamantanes (amantadine and rimantadine), but susceptible to neuraminidase inhibitors (NAIs) (oseltamivir and zanamivir). One strain (A/shanghai/1/2013) contained the R294K substitution in the neuraminida...

Pigs are considered to be "mixing vessels" for the emergence of influenza viruses with pandemic potential. 2009 Pandemic Influenza H1N1 further proved this hypothesis, and raised the needs for risk assessment of human cases caused by swine influenza virus. A field investigation was conducted after a case identified with infection of European avian-...

A novel reassortant influenza A (H7N9) virus emerged recently in China. In this study, a duplex real-time reverse transcription polymerase chain reaction (rRT-PCR) assay was developed for the simultaneous detection of hemagglutinin (HA) and neuraminidase (NA) genes of H7N9 influenza viruses. The sensitivity of the assay was determined to be 10 RNA...

H7N9 avian influenza is an emerging viral disease in China caused by avian influenza A (H7N9) virus. We investigated host cytokine and chemokine profiles in serum samples of H7N9 patients by multiplex-microbead immunoassays. Statistical analysis showed that IP-10, IL-6, IL-17, and IL-2 were increased in H7N9 infected patients. Furthermore, IL-6 and...

To determine whether the novel avian influenza H7N9 virus can transmit from person to person and its efficiency. Epidemiological investigations conducted after a family cluster of two patients with avian H7N9 in March 2013. Wuxi, Eastern China. Two patients, their close contacts, and relevant environments. Samples from the patients and environments...

A severe disease in humans caused by a novel avian-origin influenza A (H7N9) virus emerged in China recently, which has caused at least 128 cases and 26 deaths. Rapid detection of the novel H7N9 virus is urgently needed to differentiate the disease from other infections, and to facilitate infection control as well as epidemiologic investigations. I...

We tested blood samples from domestic and captive farmed animals in Minnesota, USA, to determine exposure to severe fever with thrombocytopenia syndrome virus and Heartland-like virus. We found antibodies against virus nucleoproteins in 10%-18% of samples from cattle, sheep, goats, deer, and elk in 24 Minnesota counties.

To study both the epidemiologic and molecular characteristics of outbreaks caused by norovirus (NoV) with its variants, in Jiangsu. 67 specimens from seven gastroenteritis outbreaks were collected from October 2012 to March 2013 in Jiangsu. NoV genegroup was detected by Real-Time RT-PCR. NoV portions of RdRp gene and VP1 gene were amplified under R...

Severe fever with thrombocytopenia syndrome virus (SFTSV), a newly discovered member of the Bunyaviridae family, is the causative agent of an emerging hemorrhagic fever, SFTS, in China. Currently, there are no vaccines or effective therapies against SFTS. In this study, a combinatorial human antibody library was constructed from the peripheral lymp...

Human infection associated with a novel reassortant avian influenza H7N9 virus has recently been identified in China. A total of 132 confirmed cases and 39 deaths have been reported. Most patients presented with severe pneumonia and acute respiratory distress syndrome. Although the first epidemic has subsided, the presence of a natural reservoir an...

We describe a case-control study performed in Jiangsu, China, to evaluate risk factors for human infection with novel avian influenza A(H7N9) virus. Twenty-five cases and 93 controls matched by age, sex, and location were included in the study. Direct contact with poultry or birds in the two weeks before illness onset, chronic medical conditions (h...

Background. Whether rapid lowering of elevated blood pressure would improve the outcome in patients with intracerebral hemorrhage is not known. Methods. We randomly assigned 2839 patients who had had a spontaneous intracerebral hemorrhage within the previous 6 hours and who had elevated systolic blood pressure to receive intensive treatment to lo...

Influenza A viruses present a significant threat to public health worldwide. High-affinity human scFv antibodies against a conserved epitope can potentially provide immunity to diverse viruses and protect against future pandemic viruses. A library of phage-displayed human scFv containing 6.0×10(8) members was generated from lymphocytes of H5N1 viru...

The Heartland virus (HLV), a new phlebovirus isolated in Missouri from patients with a history of tick bites and symptoms similar to severe fever with thrombocytopenia syndrome (SFTS), is an emerging pathogen. Genetically HLV is closely related to the newly identified bunyavirus (SFTSV) causing SFTS. In this study we tried to identify animal hosts...

A novel avian influenza A (H7N9) virus was discovered in February 2013 in China and has resulted in more than 100 comfirmed human infections including 26 fatal cases as of May 2, 2013. The situation raises many urgent questions and global public health concerns. In this study, epidemiologic characteristics of infected human cases in Jiangsu provinc...

The Heartland virus (HLV), a new phlebovirus isolated in Missouri from patients with a history of tick bites and symptoms similar to severe fever with thrombocytopenia syndrome (SFTS), is an emerging pathogen. Genetically HLV is closely related to the newly identified bunyavirus (SFTSV) causing SFTS. In this study we tried to identify animal hosts...

The aim of this study was to develop and evaluate a two-tube multiplex real-time RT-PCR assay for the detection and identification of four viral hemorrhagic fever (VHF) pathogens, severe fever with thrombocytopenia syndrome virus (SFTSV), Hantaan virus (HTNV), Seoul virus (SEOV), and dengue virus (DENV), from human clinical samples. The two-tube mu...

A highly sensitive one-step real-time RT-PCR method using a minor-groove-binding (MGB) probe was developed for detection and quantitation of severe febrile with thrombocytopenia syndrome virus (SFTSV). The assay could discriminate SFTSV infection from other related viral diseases in human with a minimum detection limit of 10 viral RNA copies/µl and...

Much less is known about the etiology of influenza-like illness in China. A continuous surveillance of 16 respiratory viruses was conducted from November 2010 to October 2011 of outpatients with influenza-like illness in Nanjing, China. The two largest general hospitals and a provincial virus laboratory in Nanjing participated in this study. Throat...

A virus known as severe fever with thrombocytopenia syndrome virus (SFTSV) was recently identified as the etiological agent of severe fever with thrombocytopenia syndrome (SFTS) in China. Reliable laboratory detection and identification of this virus are likely to become clinically and epidemiologically desirable. We developed a nearly instrument-f...

Pertussis is a highly contagious, respiratory disease associated with substantial morbidity and mortality. A rapid and reliable diagnostic method is essential for appropriate treatment and prevention. Expression profiles of circulating microRNAs (miRNAs) have been proven as new non-invasive biomarkers for infectious diseases. We aimed to investigat...

Currently, three predominant subtypes of influenza virus are prevalent in pig populations worldwide: H1N1, H3N2, and H1N2. European avian-like H1N1 viruses, which were initially detected in European pig populations in 1979, have been circulating in pigs in eastern China since 2007. In this study, six influenza A viruses were isolated from 60 swine...