Field Evaluation of a Duplex RT-RAA Assay for Rapid Detection of SARS-CoV-2 - Hebei Province, China, January 2021.

Introduction: Recently, a local cluster epidemic has occurred in Shijiazhuang City, Hebei Province. Failure to promptly identify patients with fever in rural areas was the major reason for this epidemic. Methods: We presented the field evaluation of a new real-time reverse transcription recombinase-aided amplification (RT-RAA) kit incorporating an endogenous internal control in a single-tube format, completed at the Hebei CDC from January 17, 2021 to January 27, 2021. Results: We evaluated the diagnostic performance of RT-RAA assay using automatic extracted RNA of 808 clinical samples. Compared with reverse transcriptase real-time quantitative PCR (qRT-PCR), RT-RAA kit achieved 92.41% sensitivity, 98.78% specificity and a 96.29% coincidence rate, demonstrating an excellent agreement between the RT-RAA assay and qRT-PCR assay. Furthermore, 58 samples were extracted using a manual extraction method within 5 minutes, but only samples with high nucleic acid concentration (cycle threshold value not higher than 32) could be stably detected. Discussion: The RT-RAA is more suitable to meet the needs of rapid, sensitive, and accurate detection in community-level medical institutions.

Long-term retrospective observation reveals stabilities and variations of hantavirus infection in Hebei, China.

BACKGROUND: Hemorrhagic fever with renal syndrome (HFRS) is an emerging zoonotic infectious disease caused by hantaviruses which circulate worldwide. So far, it was still considered as one of serious public health problems in China. The present study aimed to reveal the stabilities and variations of hantavirus infection in Hebei province located in North China through a long-term retrospective observation. METHODS: The epidemiological data of HFRS cases from all 11 cities of Hebei province since 1981 through 2016 were collected and descriptively analyzed. The rodent densities, species compositions and virus-carrying rates of different regions were collected from six separated rodent surveillance points which set up since 2007. The molecular diversity and phylogenetic relationship of hantaviruses circulating among rodents were analyzed based on partial viral glycoprotein gene. RESULTS: HFRS cases have been reported every year in Hebei province, since the first local case was identified in 1981. The epidemic history can be artificially divided into three phases and a total of 55,507 HFRS cases with 374 deaths were reported during 1981-2016. The gender and occupational factors of susceptible population were invarible throughout, however age of that was gradually aging. The annual outbreak peak always present in spring, while the main epidemic region had gradully altered from south to northeast. Surveillance of rodents revealed that residential rodents significantly possessed higher density and virus-carring rate than field rodents. The house rat, Rattus norvegicus, was the dominant rodent species and Seoul virus S3 sub-genotype which is continued but slightly evolving perhaps to be the sole pathogen for local HFRS cases of Hebei province. CONCLUSIONS: This long-term province-wide surveillance and epidemiological analysis has revealed the stabilities and variations of hantavirus infection in North China. In order to improve current prevention and control strategies of HFRS in China, all surveillance should be continuously enhanced and variations should be paid more attentions.

Spatiotemporal patterns of hemorrhagic fever with renal syndrome in Hebei Province, China, 2001-2016.

Hemorrhagic fever with renal syndrome (HFRS) is highly endemic in China, where approximately 90% of the total human cases in the world are reported. The Hebei province, one of areas with the highest prevalence, has reported HFRS cases every year in the last two decades. This study describes the spatiotemporal patterns of HFRS in the Hebei province from 2001 to 2016, detects the high-risk spatiotemporal clusters of HFRS, and provides valuable information for planning and implementation of local preventive measures. For the purpose of the analysis, HFRS cases recorded during the sixteen years in the Hebei province were aggregated into three temporal periods (2001-2006, 2007-2012, and 2013-2016). Spatiotemporal analyses, including Global spatial autocorrelation analysis and Kulldorff's scan statistical analysis, were applied to analyze te spatiotemporal clusters of HFRS at the county level. The results revealed that the spatial extent of the HFRS epidemic in the Hebei province changed dynamically from 2001 to 2016, which indicated that a comprehensive preventative strategy should be implemented in the northeastern regions of the Hebei province in spring.

Association between TNF-α-238G/A gene polymorphism and OCD susceptibility: A meta-analysis.

BACKGROUND: Tumor necrosis factor-alpha (TNF-α) is an important cytokine and has been reported to be associated with the pathogenesis of many autoimmune and inflammatory diseases. TNF-α gene is located on a region that has been found to be associated with obsessive-compulsive disorder (OCD). We performed this meta-analysis to assess the relationship between susceptibility to OCD and the TNF-α-238G/A gene polymorphism. METHODS: An extensive search of the available literature on the association between the susceptibility to OCD and the TNF gene polymorphism was conducted by searching PubMed, Web of Knowledge, Embase, Chinese Web of Knowledge, Wanfang, and Chongqing VIP database. The database was searched up to December 2016 and includes language of English and/or Chinese with the keywords of "obsessive-compulsive disorder" or "OCD," polymorphism or variant or mutation, "tumor necrosis factor" or "TNF" or "cytokine." The association between TNF-α-238G/A gene polymorphism and the susceptibility of OCD was anticipated by odds ratio (OR) with the corresponding 95% confidence interval (95% CI). RESULTS: Four studies including 435 cases and 1073 controls were incorporated in our meta-analysis. In general, TNF-α-238G/A gene polymorphism might lead to a decreased risk of OCD susceptibility (G vs A genotype model: OR = 1.01, 95% CI = 0.37-2.77, P = .981; GG vs AA+AG model: OR = 0.93, 95% CI = 0.37-2.36, P = .879; GG+AG vs AA model: OR = 0.22, 95% CI = 0.06-0.73, P = .014; GG vs AA model: OR = 0.21, 95% CI = 0.06-0.71, P = .012; AG vs AA model: OR = 0.29, 95% CI = 0.07-1.16, P = .081; GG+AA vs AG model: OR = 1.17, 95% CI = 0.55-2.51, P = .683). CONCLUSION: TNF-α-238G/A gene polymorphism might lead to a decreased risk of OCD susceptibility.

Genesis and Spread of Newly Emerged Highly Pathogenic H7N9 Avian Viruses in Mainland China.

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.IMPORTANCE 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.

Development of a highly sensitive real-time nested RT-PCR assay in a single closed tube for detection of enterovirus 71 in hand, foot, and mouth disease.

Enterovirus 71 (EV71) is one of the major causative agents of outbreaks of hand, foot, and mouth disease (HFMD). A commercial TaqMan probe-based real-time PCR assay has been widely used for the differential detection of EV71 despite its relatively high cost and failure to detect samples with a low viral load (Ct value > 35). In this study, a highly sensitive real-time nested RT-PCR (RTN RT-PCR) assay in a single closed tube for detection of EV71 in HFMD was developed. The sensitivity and specificity of this assay were evaluated using a reference EV71 stock and a panel of controls consisting of coxsackievirus A16 (CVA16) and common respiratory viruses, respectively. The clinical performance of this assay was evaluated and compared with those of a commercial TaqMan probe-based real-time PCR (qRT-PCR) assay and a traditional two-step nested RT-PCR assay. The limit of detection for the RTN RT-PCR assay was 0.01 TCID50/ml, with a Ct value of 38.3, which was the same as that of the traditional two-step nested RT-PCR assay and approximately tenfold lower than that of the qRT-PCR assay. When testing the reference strain EV71, this assay showed favorable detection reproducibility and no obvious cross-reactivity. The testing results of 100 clinical throat swabs from HFMD-suspected patients revealed that 41 samples were positive for EV71 by both RTN RT-PCR and traditional two-step nested RT-PCR assays, whereas only 29 were EV71 positive by qRT-PCR assay.

Genovariation Study of Hantavirus in Main Endemic Areas of Hemorrhagic Fever with Renal Syndrome in Hebei Province, China.

BACKGROUND: Hemorrhagic fever with renal syndrome (HFRS) is an important infectious disease in Hebei Province. At present, cases from the northeast regions of the province account for >80% of the total incidences. However, studies that examine the region-specific genetic variations of the Hantavirus (HV), the causative pathogen for HFRS, have been lacking. METHODS: Rodents were collected in northeast Hebei Province from 2004 to 2013, and the HV strains used in this study were isolated in 1993. Lung tissues were isolated from the rodents and HV antigen was detected by indirect immunofluorescence. The M1 and M2 fragments of HV M region were amplified by reverse transcription polymerase chain reaction (RT-PCR), cloned into pMDl9-T vector, sequenced and compared with representative standard stains for homology and phylogenetic analysis. RESULT: A total of 21 samples of HV antigen-positive were collected. Real-time PCR analysis revealed that the 19 rodent lungs and two HV strains were positive for the SEO virus. 11 samples were chosen to sequence, and they shared 95.8%-99.8% in nucleotide homology, and 83.6%-99.2% when compared to the standard strains of SEO virus. Phylogenetic analysis demonstrated that all strains were grouped into the same S3 subtype. CONCLUSION: SEO was the major epidemic genotype of HV in the main HFRS endemic areas in Hebei Province, and S3 was the major subtype. There was minor genetic variation in HV over short term periods, while long term variations were higher.

Pulmonary and central nervous system pathology in fatal cases of hand foot and mouth disease caused by enterovirus A71 infection.

In the past 17 years, neurological disease associated with enterovirus A71 (EV-A71) has increased dramatically in the Asia-Pacific region with a high fatality rate in young infants, often due to pulmonary oedema, however the mechanism of this oedema remains obscure. We analysed the brainstem, heart and lungs of 15 fatal cases of confirmed EV-A71 infection in order to understand the pathophysiological mechanism of death and pulmonary oedema. In keeping with other case studies, the main cause of death was neurogenic pulmonary oedema. In the brainstem, 11 cases showed inflammation and all cases showed parenchymal inflammation with seven cases showing moderate or severe clasmatodendrosis. No viral antigen was detected in sections of the brainstem in any of the cases. All fatal cases showed evidence of pulmonary oedema; however, there was absence of direct pulmonary viral damage or myocarditis-induced damage and EV-A71 viral antigen staining was negative. Though there was no increase in staining for Na/K-ATPase, 11 of the 15 cases showed a marked reduction in aquaporin-4 staining in the lung, and this reduction may contribute to the development of fatal pulmonary oedema.

[Detection of respiratory viruses in influenza-like illness in Shijiazhuang, China in 2011].

This study aimed to investigate viral infections and the prevalence of influenza-like illness (ILI) in Shijiazhuang, China, in 2011 and to provide a scientific basis for the diagnosis and control of respiratory tract infections. Throat swab specimens were collected from 483 cases of ILI who were outpatients in the influenza surveillance sentinel hospitals in Shijiazhuang between January and December 2011. All specimens were examined by multiplex RT-PCR for the following 15 respiratory tract viruses: adenovirus (ADV), human rhinovirus (HRV), human parainfluenza virus (PIV types 1-4), influenza virus A (FluA), influenza virus B (FluB), human enterovirus (HEV), respiratory syncytial virus (RSV-A and -B), human metapneumovirus (HMPV), human coronavirus (HCoV-229E/NL63 and -OC43/HKU1), and human bocavirus (HBoV). Among the 483 cases of ILI, 214 (44.31%) were positive for viruses, including ADV (8.7%), HEV (8.7%), RSV-A (8.07%), HRV (7.45%), FluA (5.38%), HCoV-OC43/ HKU1 (2.9%), PIV-3 (2.9%), HMPV (1.86%), PIV-1 (1.24%), HCoV-229E/NL63 (1.04%), PIV-2 (1.04%), HBoV (0.83%), and FluB (0.41%). Twenty-six (5.38%) of all cases were co-infected with two or more viruses, most commonly HEV/HRV with other viruses. Cases of viral infection were detected throughout the year, with peaks in January and February. ADV and HRV were detected throughout almost the whole year without obvious seasonality. HEV was detected between April and November, with a peak of prevalence in summer and autumn. FluA and FluB reached epidemic levels mainly in winter and spring. All cases of RSV were identified to be subtype A. PIV infection was mainly caused by PIV-3. The positive rate of HCoV-OC43/HKU1 infection was significantly higher than that of HCoV-229E/NL63. The leading five viruses that resulted in ILI Shijiazhuang in 2011 were HEV, ADV, RSV-A, HRV, and FluA, and these viruses have different epidemiological features.

Analysis of incidence and related factors of hemorrhagic fever with renal syndrome in Hebei Province, China.

BACKGROUND: Hemorrhagic fever with renal syndrome (HFRS) is an important infectious disease in Hebei province, China. The average annual incidence is 3.10/100000. Although the incidence of HFRS is stable with a general decline in trend since 2004, an increase in the trend was observed in 2011. Few studies have been conducted to investigate the underlying risk factors for this disease. METHODS: The epidemiological data of HFRS and the population data, meteorology, and remote sensing aspects of cities in Hebei province from 1999 to 2011 were collected. The epidemiological data included the population density in the region, seasonal data and rat density and rat's virus carriage rate. The data were analyzed by descriptive study, correlation analysis and multivariate linear analysis. RESULTS: There were 26837 cases of HFRS was reported from 1999 to 2011. The infection occurred mainly in males, aged 20∼49 years, who were farmers. Rattus norvegicus was the main host animal. The incidence of HFRS was related to NDVI value, rat density and rat's virus carriage rate by multiple linear regression (F = 25.936, P<0.01). The pseudo- R2value for the model was 0.644. CONCLUSION: The incidence of HFRS was related to NDVI value, rat density and rat's virus carriage rate. Control of these factors should be used to prevent HFRS in Hebei province.

Improved detection limit in rapid detection of human enterovirus 71 and coxsackievirus A16 by a novel reverse transcription-isothermal multiple-self-matching-initiated amplification assay.

Rapid detection of human enterovirus 71 (EV71) and coxsackievirus A16 (CVA16) is important in the early phase of hand-foot-and-mouth disease (HFMD). In this study, we developed and evaluated a novel reverse transcription-isothermal multiple-self-matching-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.

Epidemiology of hepatitis C virus infection and risk factor analysis in the Hebei Province, China.

BACKGROUND: In 1985, a hepatitis C virus (HCV) outbreak caused by plasmapheresis donation was reported in the Hebei Province, China. However, studies assessing the epidemic features and risk factors of HCV in the general population of Hebei have been limited until now. METHODS: The multicenter cluster sampling method was used to collect samples. The participants were interviewed. Relevant information was obtained from the general population using a standardized questionnaire, and association and logistic regression analyses were conducted. Serum samples were taken to test anti-HCV by enzyme immunoassays. RESULTS: A total of 4562 participants from 11 cities of the Hebei Province were enrolled. The average anti-HCV positive rate was 0.62% (29/4562), which was 1.07% in the rural population, compared with 0.22% in the urban population. The anti-HCV positive rate in the 40-59-year age group was higher than in those aged <40 years. History of blood transfusion and transmission in families were the main risk factors for HCV infection in this area. CONCLUSION: The anti-HCV positive rate in Hebei has decreased significantly from that two decades ago. Safety of blood products and health education about HCV still need to be improved.

A two-tube multiplex reverse transcription PCR assay for simultaneous detection of sixteen human respiratory virus types/subtypes.

There is a need for the development of a rapid and sensitive diagnosis of respiratory viral pathogens. With an intended application in provincial Centers for Diseases Control and Prevention, in this study, we present a two-tube multiplex RT-PCR assay (two-tube assay) using automatic electrophoresis to simultaneously detect sixteen common respiratory viruses. The specificity and the sensitivity of the assay were tested. The assay could detect 20-200 copies per reaction when each viral type was assayed individually, 2000 copies with 9 premixed viral targets in the multiplexed assay in tube 1, and 200 copies with 8 premixed templates in tube 2. A total of 247 specimens were used to evaluate the two-tube assay, and the results were compared with those obtained from the Luminex xTAG RVP Fast assay. The discordant results were confirmed by sequencing or by the Seeplex RV15 ACE detection kit. There were no false positives, but six false negatives occurred with the two-tube assay. In conclusion, the two-tube assay is demonstrated to have great potential for routine surveillance of respiratory virus infection in China.

A case-control study of risk factors for HIV-negative children with cryptococcal meningitis in Shi Jiazhuang, China.

BACKGROUND: Although cryptococcal meningitis (CM) is an emerging disease worldwide, there have been few studies of the characteristics and risk factors of CM in children. METHODS: We 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. RESULTS: Overall 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). CONCLUSIONS: Our 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.

Evaluation of a direct reverse transcription loop-mediated isothermal amplification method without RNA extraction for the detection of human enterovirus 71 subgenotype C4 in nasopharyngeal swab specimens.

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 (TCID(50)) 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.

Application of an autoregressive integrated moving average model for predicting the incidence of hemorrhagic fever with renal syndrome.

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.

Effectiveness of a Chinese hamster ovary cell derived hepatitis B vaccine in Chinese rural communities.

OBJECTIVE: To evaluate the effectiveness of a Chinese hamster ovary cell derived hepatitis B vaccine in a country community in Hebei Province, PR China. METHOD: A cross-sectional investigation was carried out in 4 of 7 randomly selected country communities in Zhengding County in 2005. All of the children who were born between 1997 and 1999 were selected as study objects. Their serum samples were taken to test for HBV markers, and HBsAg prevalence was compared to that of the same age group before hepatitis B vaccination in 1983. In addition, for HBsAg positive children, their mothers were visited and tested for serum HBV markers, in order to distinguish maternal HBV transmissions. RESULTS: Among the 2205 children of the selected birth cohort, 1696 (76.9%) were visited. The prevalence of HBsAg was 0.53%, and by comparing to that of before hepatitis B vaccination, the effectiveness was 95.3%, similar to that of yeast derived hepatitis B vaccines. Among 7 mothers of HBsAg positive children, 5 were HBsAg positive, indicating maternal HBV transmissions; and although one mother was HBsAg negative, her kid was not vaccinated, which indicates a horizontal transmission. As for the other kid, he was adopted and the HBV infection status of his birth mother was unknown. CONCLUSION: The effectiveness of the CHO derived hepatitis B vaccine is comparable to yeast derived ones, and after the hepatitis B vaccination maternal transmission is the most important route of spreading HBV.

[Study on the epidemiological of rotavirus diarrhea in Lulong in 2008-2009].

OBJECTIVE: To analyze the feature of epidemiological of rotavirus diarrhea in Lulong county, Hebei province. METHODS: 426 stool specimens were collected from inpatant with acute diarrhea from children less than 5 years old. Rotavirus-positive specimens were identified by ELISA kit. G/P typing assays were confirmed with multiplex seminested RT-PCR. RESULTS: Rotavirus was detected in 202 of 426 (47.42%) specimens. Genotyping of rotavirus showed that G3 was predominant (57.9%), followed by Gmix (16.3%), G9 (14.9% ), G1 (7.9%), G4 (1%), G2 (0.5%), P-genotyping showed that P [8], Pmix, P [4], P [9], type were found in 58.4%, 28.7%, 6.9% and 1% respectively. The most common G/P combination identified was G3P [8]. CONCLUSION: Group A rotaviruses was a major pathogen of diarrhea in Children in Lulong. G3P [8] was the predominant type in 2009, Gmix and Pmix abound, and G9 serotypes has become the second predominant after G3 strain in the region.