The novel low-pathogenic avian influenza A H7N9 viruses (LPAI H7N9 viruses) have been a threat to public health since their emergence in 2013 because of the high rates of mortality and morbidity that they cause. Recently, highly pathogenic variants of these avian influenza A H7N9 viruses (HPAI H7N9 viruses) have emerged and caused human infections and outbreaks among poultry in mainland China. However, it is still unclear how the HPAI H7N9 virus was generated and how it evolved and spread in China. Here, we show that the ancestor virus of the HPAI H7N9 viruses originated in the Yangtze River Delta region and spread southward to the Pearl River Delta region, possibly through live poultry trade. After introduction into the Pearl River Delta region, the origin LPAI H7N9 virus acquired four amino acid insertions in the hemagglutinin (HA) protein cleavage site and mutated into the HPAI H7N9 virus in late May 2016. Afterward, the HPAI H7N9 viruses further reassorted with LPAI H7N9 or H9N2 viruses locally and generated multiple different genotypes. As of 14 July 2017, the HPAI H7N9 viruses had spread from Guangdong Province to at least 12 other provinces. The rapid geographical expansion and genetic evolution of the HPAI H7N9 viruses pose a great challenge not only to public health but also to poultry production. Effective control measures, including enhanced surveillance, are therefore urgently needed. The LPAI H7N9 virus has caused five outbreak waves in humans and was recently reported to have mutated into highly pathogenic variants. It is unknown how the HPAI H7N9 virus originated, evolved, and disseminated in China. In this study, we comprehensively analyzed the sequences of HPAI H7N9 viruses from 28 human and 21 environmental samples covering eight provinces in China that were taken from November 2016 to June 2017. The results show that the ancestor virus of the HPAI H7N9 viruses originated in the Yangtze River Delta region. However, the insertion of four amino acids into the HA protein cleavage site of an LPAI H7N9 virus occurred in late May 2016 in the Pearl River Delta region. The mutated HPAI H7N9 virus further reassorted with LPAI H7N9 or H9N2 viruses that were cocirculating in poultry. Considering the rapid geographical expansion of the HPAI H7N9 viruses, effective control measures are urgently needed.

Abstract. The Box-Jenkins approach was used to fit an autoregressive integrated moving average (ARIMA) model to the incidence of hemorrhagic fever with renal Syndrome (HFRS) in China during 1986-2009. The ARIMA (0, 1, 1) + (2, 1, 0) 12 models fitted exactly with the number of cases during January 1986-December 2009. The fitted model was then used to predict HFRS incidence during 2010, and the number of cases during January-December 2010 fell within the model's confidence interval for the predicted number of cases in 2010. This finding suggests that the ARIMA model fits the fluctuations in HFRS frequency and it can be used for future forecasting when applied to HFRS prevention and control.

c Rapid detection of human enterovirus 71 (EV71) and coxsackievirus A16 (CVA16) is important in the early phase of hand-footand-mouth disease (HFMD). In this study, we developed and evaluated a novel reverse transcription-isothermal multiple-selfmatching-initiated amplification (RT-IMSA) assay for the rapid detection of EV71 and CVA16 by use of reverse transcriptase, together with a strand displacement DNA polymerase. Real-time RT-IMSA assays using a turbidimeter and visual RT-IMSA assays to detect EV71 and CVA16 were established and completed in 1 h, and the reported corresponding real-time reverse transcription-loop-mediated isothermal amplification (RT-LAMP) assays targeting the same regions of the VP1 gene were adopted as parallel tests. Through testing VP1 RNAs transcribed in vitro, the real-time RT-IMSA assays exhibited better linearity of quantification, with R 2 values of 0.952 (for EV71) and 0.967 (for CVA16), than the real-time RT-LAMP assays, which had R 2 values of 0.803 (for EV71) and 0.904 (for CVA16). Additionally, the detection limits of the real-time RT-IMSA assays (approximately 937 for EV71 and 67 for CVA16 copies/reaction) were higher than those of real-time RT-LAMP assays (approximately 3,266 for EV71 and 430 for CVA16 copies/reaction), and similar results were observed in the visual RT-IMSA assays. The new approaches also possess high specificities for the corresponding targets, with no cross-reactivity observed. In clinical assessment, compared to commercial reverse transcription-quantitative PCR (qRT-PCR) kits, the diagnostic sensitivities of the real-time RT-IMSA assays (96.4% for EV71 and 94.6% for CVA16) were higher than those of the real-time RT-LAMP assays (91.1% for EV71 and 90.8% for CVA16). The visual RT-IMSA assays also exhibited the same results. In conclusion, this proof-of-concept study suggests that the novel RT-IMSA assay is superior to the RT-LAMP assay in terms of detection limit and has the potential to rapidly detect EV71 and CVA16 viruses. Hand-foot-and-mouth disease (HFMD) is a childhood syndrome and is characterized by tiny blisters on the skin and oral mucosa together with fever and poor appetite. The two major causative agents of HFMD are human enterovirus 71 (EV71) and coxsackievirus A16 (CVA16). EV71-related HFMD commonly accounts for the fatal cases, due to severe complications, such as brainstem encephalitis and rapid fatal pulmonary edema, whereas CVA16-related HFMD usually presents with mild symptoms (1-3). Since no vaccine or antiviral drugs are currently available to treat HFMD, the early and rapid detection of EV71 and CVA16 are critical for the prevention and control of HFMD infection.Presently, laboratory detection of EV71 and CVA16 includes traditional virus isolation, neutralization, and nucleic acid amplification techniques. It is difficult to achieve rapid detection using traditional virus isolation and neutralization because of their low specificities and detection limits, as well as the long time that is spent obtaining results (4-6). Nucleic acid a...

Human enterovirus 71 (EV71) is the major causative agent of hand, foot, and mouth disease (HFMD) worldwide and has been associated with neurological complications which resulted in fatalities during recent outbreak in Asia pacific region. A direct reverse transcription loop-mediated isothermal amplification (direct RT-LAMP) assay using heat-treated samples without RNA extraction was developed and evaluated for the detection of EV71 subgenotype C4 in nasopharyngeal swab specimens. The analytical sensitivity and specificity of the direct RT-LAMP assay were examined. The detection limit of the direct RT-LAMP assays was 1.6 of a 50% tissue culture infective dose (TCID50) per reaction and no cross-reaction was observed with control viruses including Cosackievirus A (CVA) viruses (CVA2,4,5,7,9,10,14,16, and 24), Coxsackievirus B (CVB) viruses (CVB1,2,3,4, and 5) or ECHO viruses (ECHO3,6,11, and 19). The direct RT-LAMP assay was evaluated and compared to both RT-LAMP and quantitative real-time PCR (qRT-PCR) in detecting EV71 infection with 145 nasopharyngeal swab specimens. The clinical performance demonstrated the sensitivity and specificity of direct RT-LAMP was reported to be 90.3% and 100% respectively, compared to RT-LAMP, and 86.83% and 100% respectively, compared to qRT-PCR. These data demonstrated that the direct RT-LAMP assay can potentially be developed for the point of care screening of EV71 infection in China.

BackgroundAlthough cryptococcal meningitis (CM) is an emerging disease worldwide, there have been few studies of the characteristics and risk factors of CM in children.MethodsWe used data collected from May 2007 through April 2012 in the Acute Meningitis-Encephalitis Syndrome Surveillance project in Shi Jiazhuang, China to describe the epidemiologic, clinical, and laboratory findings in children with CM. Furthermore, a matched case–control study was used to determine risk factors of CM.ResultsOverall 23 HIV-negative children with CM (median age: 10.91 years; range: 5 months-17 years) were enrolled in our study. The average annual incidence of CM was 0.43/100,000 with a fatality rate of 1.7%. Most patients were males (60.87%) and rural children (73.91%). Common clinical symptoms included increased intracranial pressure, such as headaches (78.3%), nausea (60.9%), altered mental status (56.5%), vomiting (52.2%), and seizures (43.5%), and frequent laboratory findings consisted of blood leukocytosis (87.0%), decreased CSF glucose (87.0%), pleocytosis (82.6%), increased intracranial pressure (73.9%) and elevated CSF proteins (65.2%). Epidemiologic, clinical, and laboratory findings were similar between patients with and without underlying diseases. Multivariate logistic regression analysis showed that children who had contact with birds/bird droppings or saprophytes were more likely to be infected than those without such contact (odds ratio(OR) =11.82; 95% confidence interval (CI), 2.21-62.24; P = 0.004). Patients with an interval of ≥20 days from onset to admission were at high risk for CM (OR= 5.31; 95%CI, 1.58-17.89; P = 0.007).ConclusionsOur findings show that CM is an uncommon disease with a high mortality rate in children. Although additional studies are needed to find effective prevention and treatments for CM, clinicians should consider CM as a potential cause for pediatric meningitis in children, particularly boys from rural areas, who had contact with birds/bird droppings or saprophytes and in children who did not receive prompt medical attention.