The ecology, genetic diversity, and phylogeny of Huaiyangshan virus in China.

Surveys were carried out to better understand the tick vector ecology and genetic diversity of Huaiyangshan virus (HYSV) in both regions of endemicity and regions of nonendemicity. Haemaphysalis longicornis ticks were dominant in regions of endemicity, while Rhipicephalus microplus is more abundant in regions of nonendemicity. HYSV RNA was found in human and both tick species, with greater prevalence in H. longicornis and lesser prevalence in R. microplus. Phylogenetic analyses indicate that HYSV is a novel species of the genus Phlebovirus.

Hemorrhagic fever caused by a novel Bunyavirus in China: pathogenesis and correlates of fatal outcome.

BACKGROUND: Hemorrhagic fever-like illness caused by a novel Bunyavirus, Huaiyangshan virus (HYSV, also known as Severe Fever with Thrombocytopenia virus [SFTSV] and Fever, Thrombocytopenia and Leukopenia Syndrome [FTLS]), has recently been described in China. METHODS: Patients with laboratory-confirmed HYSV infection who were admitted to Union Hospital or Zhongnan Hospital between April 2010 and October 2010 were included in this study. Clinical and routine laboratory data were collected and blood, throat swab, urine, or feces were obtained when possible. Viral RNA was quantified by real-time reverse-transcriptase polymerase chain reaction. Blood levels of a range of cytokines, chemokines, and acute phase proteins were assayed. RESULTS: A total of 49 patients with hemorrhagic fever caused by HYSV were included; 8 (16.3%) patients died. A fatal outcome was associated with high viral RNA load in blood at admission, as well as higher serum liver transaminase levels, more pronounced coagulation disturbances (activated partial thromboplastin time, thrombin time), and higher levels of acute phase proteins (phospholipase A, fibrinogen, hepcidin), cytokines (interleukin [IL]-6, IL-10, interferon-γ), and chemokines (IL-8, monocyte chemotactic protein 1, macrophage inflammatory protein 1b). The levels of these host parameters correlated with viral RNA levels. Blood viral RNA levels gradually declined over 3-4 weeks after illness onset, accompanied by resolution of symptoms and laboratory abnormalities. Viral RNA was also detectable in throat, urine, and fecal specimens of a substantial proportion of patients, including all fatal cases assayed. CONCLUSIONS. Viral replication and host immune responses play an important role in determining the severity and clinical outcome in patients with infection by HYSV.

Hemorrhagic fever caused by a novel tick-borne Bunyavirus in Huaiyangshan, China.

BACKGROUND: From April to July in 2009 and 2010, unexplained severe hemorrhagic fever-like illnesses occurred in farmers from the Huaiyangshan mountains range. METHODS: Clinical specimens (blood, urine, feces, and throat swabs) from suspected patients were obtained and stored. Mosquitoes and ticks in affected regions were collected. Virus was isolated from 2 patients and characterized by whole genome sequencing. Virus detection in additional patients and arthropods was done by virus-specific reverse transcription (RT) PCR. Clinical and epidemiological data of RT-PCR confirmed patients were analyzed. RESULTS: An unknown virus was isolated from blood of two patients and from Haemaphysalis ticks collected from dogs. Whole genome sequence analysis identified the virus as a novel member of the family Bunyaviridae, most closely related to the viruses of the genus Phlebovirus within which it forms a separate lineage. Subsequently, infection was confirmed by RT-PCR in 33 of 58 suspected patients. The illness in these patients was characterized by fever, severe malaise, nausea, vomiting, and diarrhea. Prominent laboratory findings included low white cell- and platelet counts, coagulation disturbances, and elevation of liver enzymes. Hemorrhagic complications were observed in 3 cases, 5 (15%) patients died. CONCLUSIONS: A novel tick-borne Bunyavirus causing life-threatening hemorrhagic fever in humans has emerged in the Huaiyangshan mountain areas of China. Further studies are needed to determine the epidemiology, geographic distribution and vertebrate animal ecology of this virus.

[Efficacy and safety of reduced osmolarity oral rehydration salts in treatment of dehydration in children with acute diarrhea--a multicenter, randomized, double blind clinical trial].

OBJECTIVE: To assess the efficacy and safety of reduced osmolarity oral rehydration salts (ROORS) in treatment of mild to moderate dehydration caused by acute diarrhea in children. METHODS: A multicenter, randomized, double-blind, positive drug controlled clinical trial was conducted in 125 cases aged 1 to 17 years. These children with acute diarrhea and signs of dehydration were randomly assigned to receive either ROORS (trial group, n = 62) or oral rehydration salts II (ORS II) (control group, n = 63). The volume of intravenous infusion were recorded. The improvements of systemic symtoms and signs, diarrhea, dehydration and total scores were compared between the two groups. The adverse events and changes of electrolyte and other laboratory tests during treatment were also observed and analyzed. RESULTS: The overall effective rates in trial group and control group were 96.8% and 96.8%, respectively. The recovery of systemic symptoms, dehydration signs and diarrhea occurred in 96%, 97% and 78% patients in trial groups, and 96%, 98% and 85% patients in control group. The scores of symptoms and signs in both groups decreased significantly after treatment. All the above parameters and the number of cases who needed intravenous infusion (41 vs. 39) were not statistically different between two groups. However, the average volume of intravenously infused fluids in trial group was (450.98 +/- 183.07) ml, 24.5% less than that in the control group (597.30 +/- 343.37) ml (P < 0.05). The mean serum Na(+) concentration elevated from (137.48 +/- 4.55) mmol/L to (139.52 +/- 3.25) mmol/L (P < 0.01) in control group after treatment, but the change was not statistically significant in trail group. Serum K(+), Cl(-), HCO(3)(-) and other laboratory result did not change significantly after treatment. The total scores in both groups decreased obviously after treatment, but no significant difference was demonstrated between two groups (P > 0.05). A case in trial group had mild abdominal distention and recovered spontaneously. CONCLUSION: ROORS was shown to be effective and safe in the treatment of mild and moderate dehydration induced by acute diarrhea. Compared to ORS II, ROORS could decrease the intravenous supplement of fluid and lower the risk of hypernatremia.

Hemorrhagic fever caused by a novel tick-borne Bunyavirus in Huaiyangshan,China / 中华流行病学杂志

Background:From April to July in 2009 and 2010,unexplained severe hemorrhagic fever-like illnesses occurred in farmers from the Huaiyangshan mountains range.Methods:Clinical specimens (blood,urine,feces,and throat swabs) from suspected patients were obtained and stored.Mosquitoes and ticks in affected regions were collected.Virus was isolated from 2 patients and characterized by whole genome sequencing.Virus detection in additional patients and arthropods was done by virus-specific reverse transcription (RT) PCR.Clinical and epidemiological data of RT-PCR confirmed patients were analyzed.Results:An unknown virus was isolated from blood of two patients and from Haemaphysalis ticks collected from dogs.Whole genome sequence analysis identified the virus as a novel member of the family Bunyaviridae,most closely related to the viruses of the genus Phlebovirus within which it forms a separate lineage.Subsequently,infection was confirmed by RT-PCR in 33 of 58 suspected patients.The illness in these patients was characterized by fever,severe malaise,nausea,vomiting,and diarrhea.Prominent laboratory findings included low white cell- and platelet counts,coagulation disturbances,and elevation of liver enzymes.Hemorrhagic complications were observed in 3 cases,5 (15%) patients died.Conclusions:A novel tick-borne Bunyavirus causing life-threatening hemorrhagic fever in humans has emerged in the Huaiyangshan mountain areas of China.Further studies are needed to determine the epidemiology,geographic distribution and vertebrate animal ecology of this virus.