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Background:Approximately 2 million doses of vaccine against haemorrhagic fever with renal syndrome (HFRS) have been used annually in China. However, there were limited studies focused on persistence of immune responses to HFRS vaccine in healthy adults. A phase 4, multicentre, open trial has been undertaken to assess antibody persistence after HFRS vaccination of healthy adolescents and adults aged 16–60 years. Methods:The vaccine was administered as a three-dose series at 0, 2 weeks and 6 months, including two primary doses and one booster dose. Anti-hantavirus IgG antibodies were measured by enzyme-linked immunosorbent test (ELISA) pre-vaccination and 1.5, 7 and 24 months after the initial vaccination. Results:A total of 143 individuals aged 16–60 years were included. The median OD (range) values of IgG antibody were 0.005 (0.004–0.016), 0.116 (0.036–0.620), 0.320 (0.065–0.848) and 0.128 (0.011–0.649) pre-vaccination and at 1 month after the two primary doses, 1 month after the booster dose and 18 months after the booster dose. The positivity rate was 7.7%, 40.6%, 62.2% and 48.2%, respectively. Conclusions:The two primary doses could help healthy individuals to generate an immune response, and this three-dose series may be better than a two-dose regimen. [ABSTRACT FROM AUTHOR]

Background: Increased risks for hemorrhagic fever with renal syndrome (HFRS) caused by Hantaan virus have been observed since 2005, in Xi'an, China. Despite increased vigilance and preparedness, HFRS outbreaks in 2010, 2011, and 2012 were larger than ever, with a total of 3,938 confirmed HFRS cases and 88 deaths in 2010 and 2011. Methods and Findings: Data on HFRS cases and weather were collected monthly from 2005 to 2012, along with active rodent monitoring. Wavelet analyses were performed to assess the temporal relationship between HFRS incidence, rodent density and climatic factors over the study period. Results showed that HFRS cases correlated to rodent density, rainfall, and temperature with 2, 3 and 4-month lags, respectively. Using a Bayesian time-series Poisson adjusted model, we fitted the HFRS outbreaks among humans for risk assessment in Xi'an. The best models included seasonality, autocorrelation, rodent density 2 months previously, and rainfall 2 to 3 months previously. Our models well reflected the epidemic characteristics by one step ahead prediction, out-of-sample. Conclusions: In addition to a strong seasonal pattern, HFRS incidence was correlated with rodent density and rainfall, indicating that they potentially drive the HFRS outbreaks. Future work should aim to determine the mechanism underlying the seasonal pattern and autocorrelation. However, this model can be useful in risk management to provide early warning of potential outbreaks of this disease. Author Summary: Hemorrhagic fever with renal syndrome (HFRS, caused by hantavirus) is a zoonotic infectious disease reservoired in rodent populations worldwide, but with 90% of the total cases occurring in China. Xi'an is one of the most endemic areas in China, with a total of 7,748 confirmed HFRS cases from 2005 to 2012. HFRS came to the attention of the public when two larger outbreaks occurred in Xi'an in 2010 and 2011, with 1,366 and 1,067 cases being reported, respectively. By using 8 years of surveillance data (2005–2012) on HFRS dynamics, including data on the main rodent host reservoir, human cases, and weather conditions, we show how the epidemic dynamics of HFRS were associated with seasonality, rodent abundance, rainfall, and temperature. We find that the two larger HFRS outbreaks coincided with the abrupt increase of rodent abundance and/or rainfall. We present a statistical model revealing strong effects of seasonality and autocorrelation and additional effects of rodent density and rainfall on HFRS incidence that gives robust prediction; this approach could be a very practical tool in Xi'an. [ABSTRACT FROM AUTHOR]

Summary Background Severe fever with thrombocytopenia syndrome (SFTS) is an emerging infectious disease discovered in China in 2009. In July 2013, the first human infection with SFTS virus (SFTSV) was detected in Shaanxi Province, Western China. Methods A seroprevalence study among humans was carried out in an SFTS endemic village; specifically, serum samples were collected from 363 farmers in an SFTS endemic village in Shaanxi Province. The presence of SFTSV antibodies in serum was determined using an ELISA. Results SFTSV antibodies were found in a total of 20 people (5.51%), with no significant difference between males and females (6.93% and 4.42%, respectively; Chi-square = 1.29, p = 0.25). Moreover, the SFTSV antibody positive rate was not significantly different across different age groups (Chi-square = 2.23, p = 0.69). Conclusions SFTSV readily infects humans with outdoor exposure. The results of the serological study indicate that the virus circulates widely in Shaanxi Province. SFTSV represents a public health threat in China. [ABSTRACT FROM AUTHOR]

Objective: Analysis the viral pathogenic spectrum for patients with fever and respiratory tract infection syndrome in Shaanxi province during 2010 and investigate the molecular epidemiology characteristics of respiratory syncytial virus., Methods: A total of 208 patients' pharyngeal swabs were collected based on surveillance definition from January 2010 to January 2011 and screened for sixteen human respiratory virus types/subtypes by Qiaxcel-based multiplex reverse transcription-PCR assay, including HRV,HCoV, Flu, HPIV, ADV, HRSV, HMPV and HBoV and investigate molecular epidemiology of HRSV by sequencing and phylogenetic analysis of the C-terminal second hypervariable region of the G gene., Results: 109 out of 208 specimens (53%) were positive for one or more viruses. HRSV(42. 2%) was the dominant pathogen detected, followed by Flu(24. 5%), PIV(20%), HRV(13.6%) and ADV( 10.9%),there were also 8 strains of HCoV, 5 strains of HMPV and 3 strains of HBoV detected. The results showed that 22 specimens were positive for two or more viruses, PIV (14/22) was the most frequently detected viral agent among co-infection specimens, and the highest incidence of mixed infection is aged 15-39 years group (P < 0.05). The overall viral detection rate was no related to age. In addition to Flu, HMPV and PIV, other viruses (HRV, HBoV, HCoV, ADV, RSV) mainly infected 0 to 4 years old children. Among 46 HRSV positive specimens, 42 HRSV-A strains clustered into NA1 genotype and two HRSV-B strains clustered into two genotypes, BA9 and GB2., Conclusion: HRSV is the dominate pathogen collected from patients with fever and respiratory tract infection syndrome in Shaanxi and HRSV A is the predominant subtype. For most viruses, infection was most prevalent among children aged <4 years. PIV was the most common pathogen in co-infection.