Clinical and epidemiological characteristics of laboratory confirmed cases of severe fever with thrombocytopenia syndrome infection in Shandong Province, China / 中国人兽共患病学报

We investigated the clinical and epidemiological characteristics of laboratory confirmed cases of severe fever with thrombocytopenia syndrome (SFTS) in Shandong Province,China.A descriptive epidemiological method combined with case investigation was used in this study.Cases information were collected by standard questionnaire and analyzed by Epidata3.1,SPSS 17.0 and ArcGIS10.0 software.Results showed that a total of 154 cases were analyzed and the case fatality rate was 7.1％.Epidemic peak was from May to October,the high incidence areas were located in the middle and east hilly areas of Shandong Province.The characteristic of SFTS cases were farmers (93.5％),and the age was over 40 years.Most of them were living in the hilly areas (85.7 ％),and had outdoor activities within the previous 2 weeks prior to fever onset (83.8 ％).The 16.8％ of them had tick bites history.Tick carrying rates of sheep,cattle,dogs and cats were 66.7％,40％,34.3％ and 12.5％,respectively.Directly contact with bloody secretion of SFTS death cases can be infected with the disease.Major symptoms include high fever (98.1％),anorexia (90.9 ％),fatigue (53.3％),thrombocytopenia (73.4 ％) and leukocytopenia (60.4 ％).The 35.7 ％ cases need to go through more than three referrals for treatment,the interval time between onset and diagnosis was 5 days(3-15),only hospitals above county level can make the correct diagnosis of the disease.Compared with survival patients,the death cases were elderly patients (t =2.03,P=0.044) and with bleeding performance (x2 =13.09,P＜0.01).In conclusion,SFTS is a severe disease with high mortality.Living hilly environment,doing agricultural labor,feeding animals,tick carrying rates of animals and direct contacting with bloody secretion of deaths maybe possible risk factors.To reduce morbidity and mortality of SFTS,measures should be carried out to propagandize the basic knowledge for SFTS prevention and control and to improve the medical treatment skills of doctors in the epidemic foci.

Analysis of clinical features and early warning indicators of death from hand, foot and mouth disease in Shandong province / 中华预防医学杂志

<p><b>OBJECTIVE</b>To understand the clinical features of death from hand, foot and mouth disease (HFMD) and to explore the early warning index of HFMD death.</p><p><b>METHODS</b>A total of 41 HFMD death cases were collected as case group in Shandong province between 2009 and 2011, and another 123 serious HFMD cases were selected as control group according to the similar gender, place of origin and hospital level, with the ratio at 1:3. We investigated the general situation, clinical treatment, past medical history, clinical symptoms and signs of the ill children, and applied the conditional logistic regression to explore early warning index of HFMD death.</p><p><b>RESULTS</b>The rate of patients who had symptoms in nervous system, digestive system, circulatory system and respiratory system were separately 90.2% (37/41), 58.5% (24/41), 53.7% (22/41) and 90.2% (37/41) in case group; and the proportions were 44.7% (55/123), 13.8% (17/123), 10.6% (13/123) and 12.2% (15/123) respectively in control group. The difference between the two groups showed statistical significance (χ(2) = 25.881, 32.791, 34.011, 86.505, P < 0.05). In case group, 37 patients had neurogenic pulmonary edema, 26 patients got encephalitis, 15 patients had respiratory and circulatory failure, 7 patients got pulmonary hemorrhage, 4 patients had multiple organ failure, 4 patients got myocarditis and 1 patient had cerebral hernia. According to multi-factor logistic regression analysis, the early warning indicators of HFMD death included neck resistance (case group: 34.1% (14/41), control group: 4.1% (5/123); OR = 7.145, 95%CI: 1.748 - 29.204), vomiting (case group: 58.5% (24/41), control group: 13.8% (17/123); OR = 5.632, 95%CI: 1.793 - 17.685) and increase of heart rate (case group: 53.7% (22/41), control group: 10.6% (14/123), OR = 6.370, 95%CI: 1.517 - 26.743).</p><p><b>CONCLUSION</b>In the process of clinical treatment and care, we should interfere the serious HFMD patients with neck resistance, vomiting and increase of heart rate, and thereby reduce the death from HFMD.</p>

The infection status and epidemic rule of new bunia virus in the livestock and poultry in hilly area of Jiaodong peninsula / 中华预防医学杂志

<p><b>OBJECTIVE</b>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.</p><p><b>METHODS</b>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.</p><p><b>RESULTS</b>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.</p><p><b>CONCLUSION</b>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.</p>

Isolation, identification and characterization of SFTS bunyavirus from ticks collected on the surface of domestic animals / 病毒学报

To understand the maintenance and transmission of SFTS virus, the potential vector ticks were collected from sheep, cattle and dogs in the endemic areas of SFTSV in Shandong Province. Among the collected ticks, the dominant species was H. longicornis ticks. Real-time PCR for RNA detection, virus isolation and characterization, genomic sequencing, phylogenetic and antigenic analysis were performed in this investigation. The results showed that the SFTS viral RNA was detected in 2.14% H. longicornis, and a SFTS virus was isolated from one of viral RNA positive ticks collected from sheep. Whole genome analysis of the SFTSV isolates with 11 human-origin SFTS virus revealed a highly pairwise similarity, and the growth curve analysis showed nearly identical in virus yield and the dynamic of virus reproduction compared to human derived viral isolates. Immunofluorescence and neutralization test showed identical serological reaction character of the two different origin viral strains. In this study, the characters of a SFTSV isolate was firstly described, which suggested that the tick species H. longicornis acting important vector role in the transmission of SFTS virus.

Analysis of epidemic features of scrub typhus between year 2006 and 2010 in Shandong province, China / 中华预防医学杂志

<p><b>OBJECTIVE</b>To explore the epidemic features of scrub typhus between year 2006 and 2010 in Shandong Province.</p><p><b>METHODS</b>Based on the data collected through Diseases Reporting Information System between year 2006 and 2010 in Shandong province, 1291 cases of scrub typhus were selected. The study described the population distribution features of the scrub typhus patients, and explored the temporal and spatial distribution features of the disease by applying the methods of spatial thematic mapping, inverse distance weighted, spatial autocorrelation analysis, spatial clustering analysis, temporal clustering analysis and spatial variation analysis in temporal trends based on Geographic Information software (ArcGIS 9.3) and Spatial Clustering Software (SatScan 7.0).</p><p><b>RESULTS</b>The onset age of the 1291 patients ranged between 1 and 92 years old.639 out of 1291 patients were over 55 years old, accounting for 49.5%.640 patients were male and the other 651 patients were female, occupying 49.6% and 50.4% respectively. The gender ratio was 1:1.02. Patients were found in farmers, workers, students and preschool children. However, most of the cases were farmers, up to 84.8% (1095/1291). Global Moran's I index was 0.324 (P < 0.01). The local Moran's I index in 8 locations were proved to have statistical significance (P < 0.01); all of which were H-H clustering areas. Gangcheng (38 cases), Laicheng (154 cases), Xintai (160 cases) and Donggang (105 cases) were important locations, whose local Moran's I index were 2.111, 1.642, 1.277 and 0.775 respectively. The clustering period of scrub typhus in respective year were as follows: 2006.09.23 - 2006.11.20 (202 cases), 2007.10.02 - 2007.11.11 (197 cases), 2008.09.30 - 2008.11.07 (302 cases), 2009.09.25 - 2009.11.10 (204 cases), and 2010.10.05 - 2010.11.13 (226 cases), whose RR values were separately 45.55, 34.60, 50.64, 53.09 and 79.84 (P < 0.01). Two spatial clustering area were found in the study, one was the area centered Taian and Xintai with radiation radius at 58.28 km (542 cases) and the other one was the area centered Rizhao and Donggang with radiation radius at 22.68 km (134 cases), whose RR values were 4.52 and 3.96 (P < 0.01). The spatial features of the two clustering areas were inland low hills area and coastal hills area. The highest annual growth rate of the disease was 45.04%, found in the area centered Linyi and Mengyin counties, with the radiation radius at 45.82 km. The RR value was 3.68 (P < 0.01).</p><p><b>CONCLUSION</b>The majority of the scrub typhus patients were middle-aged and elderly farmers. The epidemic peak was between the last 10 days of September and the first 10 days of November. A positive spatial correlation of the disease was found; and most cases clustered in inland low hills area and costal hills area; especially the area around Linyi and Mengyin, with the highest annual growth rates of the disease.</p>

Study on the characteristics of temporal distribution and the epidemic trend of autumn-winter type scrub typhus under time series analysis / 中华流行病学杂志

Objective To explore the characteristics of temporal distribution and epidemic trend of autumn-winter type scrub typhus using the time series analysis.Methods Based on the data of scrub typhus collected from Shandong Diseases Reporting Information System from 2006 to 2011,both spectral analysis and moving average analysis were used to analyze the annual data of scrub typhus while scrub typhus incidence in 2012-2014 was forecasted.Seasonal decomposition analysis was applied to analyze the monthly data from January of 2006 to October of 2011,followed by Autoregressive Integrated Moving Average Model (ARIMA) which was constructed to forecast case number in November and December of 2011 and compared to the actual incidence.Results The results of spectral analysis showed that the prevalence of autumn-winter type scrub typhus had a feature of ‘3-year-periodicity’.A long-term up-trend was confirmed by method of moving average analysis,with annually case numbers of 310,337 and another number of 366 forecasted for 2012 to 2014,respectively,with the annual increase rate as 9％ per-year.Data from analysis of monthly data of scrub typhus showed that through multiple seasonal decomposition analysis,the results indicated that the prevalence of this disease possessed a typical autumn-winter type.The seasonality indexes for scrub typhus in October and November were 8.454 and 2.230,respectively,while others were less than 1.000.The ARIMA (0,1,1 ) (0,1,0)12 model of ( 1 -B) ( 1 -B12)X,=( 1 -0.811B)u,that was used to forecast the prevalence of autumn-winter type scrub typhus and was constructed with the residual error of 16 lags as white noise.The Box-Ljung test statistic for the model was 3.116,giving a P value of 0.999.The model fitted the data well.Good accordance was achieved between the observed values and the forecasted values of scrub typhus in November and December of 2011 which was produced by the ARIMA model,and all observed values were within the forecasted 95％ CI.Conclusion The prevalence of autumn-winter type scrub typhus showed a 3-year-periodicity,with a long-term up-trend,and the case numbers of 2012 to 2014 were forecasted,rising on the end with an increasing rate of 9％ per year,which occurred seasonally with October as the peak time in every year.The ARIMA (0,1,1 ) (0,1,0) 12 model seemed to be quite appropriate in predicting the autumn-winter type scrub typhus.

Molecular epidemiology investigation of rabies virus nucleoprotein genes in China / 中华实验和临床病毒学杂志

<p><b>OBJECTIVE</b>To study the relationship between the distribution of rabies virus and genetic variation, the genetic characterization and variation of rabies virus strains in China were analyzed.</p><p><b>METHODS</b>The downstream 720 nucleotides of Nucleoprotein (N) gene coding region of the rabies specimens from different areas and host animals were sequenced, and then homology and phylogenesis were analyzed.</p><p><b>RESULTS</b>Nucleotide similarities of 34 N gene sequences were 87.5%-100%, and the deduced amino acid similarities were 93.3%-99.6%. Most of the nucleotide variations were synonymous mutations.</p><p><b>CONCLUSION</b>The 34 rabies specimens all belong to genotype I and are of regional characteristic. The rabies viruses in high-incidence areas in China are of various origins and present the transmission tendency from high-incidence areas to surrounding regions. There may be cross-infection and mutual spread of rabies virus between wildlife and domestic animals as well as native and foreign animals.</p>