Molecular epidemiology analysis of symptomatic and asymptomatic norovirus infections in Chinese infants.

BACKGROUND: Norovirus is a leading cause of acute gastroenteritis among children. Previous studies based on symptomatic infections indicated that mutations, rather than recombination drove the evolution of the norovirus ORF2. These characteristics were found in hospital-based symptomatic infections, whereas, asymptomatic infections are frequent and contribute significantly to transmission. METHODS: We conducted the first norovirus molecular epidemiology analysis covering both symptomatic and asymptomatic infections derived from a birth cohort study in the northern China. RESULTS: During the study, 14 symptomatic and 20 asymptomatic norovirus infections were detected in 32 infants. Out of the 14 strains that caused symptomatic infections, 12 strains were identified as GII.3[P12], and others were GII.4[P31]. Conversely, 17 asymptomatic infections were caused by GII.4[P31], two by GII.2[P16], and one by GII.4[P16]. Regardless of symptomatic and asymptomatic infections, the mutations were detected frequently in the ORF2 region, and almost all recombination were identified in the RdRp-ORF2 region. The majority of the mutations were located around the predefined epitope regions of P2 subdomain indicating a potential for immune evasion. CONCLUSION: The role of symptomatic as well as asymptomatic infections in the evolution of norovirus needs to be evaluated continuously.

Safety and immunogenicity of a novel oral hexavalent rotavirus vaccine：a phase I clinical trial.

Background Rotavirus infections, prevalent in human populations, are caused mostly by group A viruses. Immunization against rotaviruses in infancy is currently the most effective and economical strategy to prevent rotavirus infection. This study evaluated the safety of a novel hexavalent rotavirus vaccine and analyzed its dose and immunogenicity.Methods This randomized, double-blinded, placebo-controlled phase I clinical trial enrolled healthy adults, toddlers, and infants in Zhengding County, Hebei Province, northern China. 40 adults and 40 children were assigned in a 2:1:1 ratio to receive one vaccine dose, placebo 1, and placebo 2, respectively. 120 6-12 week old infants were assigned equivalently into 3 groups. The infants in each group were assigned in a 2:1:1 ratio to receive three doses of vaccine, placebo 1, and placebo 2, at a 28-day interval. Adverse events (AEs) until 28 days after each dose and serious adverse events (SAEs) until 6 months after the third dose were reported. Virus shedding until 14 days after each dose in infants was tested. Geometric mean concentrations (GMCs) and seroconversion rates were measured for anti-rotavirus IgA by using an enzyme-linked immunosorbent assay (ELISA).Results The solicited and unsolicited AE frequencies and laboratory indexes were similar among the treatment groups. No vaccine-related SAEs were reported. The average percentage of rotavirus vaccine shedding in the infant vaccine groups was 5.00%. The post-3rd dose anti-rotavirus IgA antibody geometric mean concentrations (GMC) and seroconversion rate were higher in the vaccine groups than in the placebo groups.Conclusions The novel oral hexavalent rotavirus vaccine was generally well-tolerated in all adults, toddlers and infants, and the vaccine was immunogenic in infants.

Genetic susceptibility to rotavirus infection in Chinese children: a population-based case-control study.

Rotaviruses (RVs) are the leading cause of acute gastroenteritis in children, while histo-blood group antigens (HBGAs) are believed to be host attachment and susceptibility factors of RVs. A large case-control study nested in a population-based diarrhea surveillance targeting children <5 y of age was performed in rural Hebei province, north China. Saliva and serum samples were collected from all participants to determine HBGA phenotyping, FUT2 mutations, and RV IgG antibody titers. A logistic model was employed to assess the association between host HBGA secretor status and risk of RV infection. Among 235 RV cases and 680 non-diarrhea controls studied, 82.4% of participants were IgG positive by an average age of 77 months. Out of the 235 RV cases, 216 (91.9%) were secretors, whereas the secretor rate was 76.3% in the non-diarrhea controls, resulted in an adjusted OR of 3.0 (95%CI: 1.9-4.7, P < .0001) between the two groups. Our population-based case-control study indicated a strong association between host HBGA secretor status and risk of RV infection in Chinese children. The high prevalence of Lewis-positive secretor status strongly suggests that Chinese children may be genetically susceptible to current co-circulating RV strains, and thus, a universal childhood immunization program against RV disease should be successful in China.

Immune response to different types of hepatitis B vaccine booster doses 2-32 years after the primary immunization schedule and its influencing factors.

OBJECTIVE: To assess the immune effect of different types of hepatitis B vaccine (HepB) booster doses 2-32 years after primary immunization, explore the influencing factors, and offer guidance regarding the necessity and timing of boosters. METHODS: In total, 1163 participants who were born from 1986 to 2015, received the HepB full-course primary vaccination, were hepatitis B surface antigen (HBsAg) and hepatitis B core antibody (anti-HBc) negative, and had hepatitis B surface antibody (anti-HBs) <10 mIU/mL were enrolled. Individuals were randomly divided into two groups and received a booster dose of HepB. Venous blood samples were collected 30 days later and tested for anti-HBs. RESULTS: In total, 595 and 568 individuals received a single dose of HepB (CHO) and HepB (SC), respectively. Venous blood samples were obtained from 1079 vaccinees (CHO: 554, SC: 525). The seroconversion rates were 93.68% (519/554) and 86.67% (455/525) (p < 0.05), with geometric mean concentrations (GMCs) of 426.58 mIU/ml and 223.8 mIU/ml, respectively. This result indicated that BMI, smoking status, vaccine types of booster and prebooster anti-HBs concentration significantly influenced anti-HBs levels. Only BMI, prebooster anti-HBs concentrations and booster types were different between the anti-HBs positive and negative groups. CONCLUSIONS: Participants boostered with HepB (CHO) had a relatively higher seroconversion rate than those boostered with HepB (SC). The high seroconversion rates in the two groups suggested that the subjects remained protected despite low circulating antibodies, so there is currently no urgent need for booster immunization. Factors including BMI ≥ 25 and prebooster anti-HBs concentration <2.5 mIU/mL, which contributed to lower responses to a booster dose, might indicate a greater risk of breakthrough infection.

Burden of viral gastroenteritis in children living in rural China: Population-based surveillance.

BACKGROUND: Despite the considerable disease burden caused by the disease, rotavirus vaccine has not been introduced into routine national immunization schedule, and norovirus vaccines are being developed without a comprehensive understanding of gastroenteritis epidemiology. To bridge this knowledge gap, we investigated the disease burden of viral gastroenteritis in rural China. METHODS: Between October 2011 and December 2013, population-based surveillance was conducted in Zhengding and Sanjiang counties in China. Stool samples were collected from children <5 years of age with diarrhea. All specimens were tested for rotaviruses, noroviruses, sapoviruses, enteric adenoviruses, and astroviruses. RESULTS: The most common pathogen causing diarrhea was rotavirus (54.7 vs 45.6 cases/1,000 children/year in Zhengding and Sanjiang, respectively), followed by norovirus (28.4 vs 19.3 cases/1,000 children/year in Zhengding and Sanjiang, respectively). The highest incidence of these viruses was observed in children 6-18 months of age. Among the 5 viral pathogens, rotaviruses caused the most severe illness, followed by noroviruses. CONCLUSION: Rotavirus and norovirus are the 2 most important viral pathogens causing childhood diarrhea in both northern and southern China; they should be the major targets for viral gastroenteritis prevention strategies among children in China.

Immune persistence 17 to 20 years after primary vaccination with recombination hepatitis B vaccine (CHO) and the effect of booster dose vaccination.

BACKGROUND: To assess the immune persistence conferred by a Chinese hamster ovary (CHO)-derived hepatitis B vaccine (HepB) 17 to 20 years after primary immunization during early life. METHODS: Participants born between 1997 and 1999 who received a full course of primary vaccination with HepB (CHO) and who had no experience with booster vaccination were enrolled. Blood samples were required from each participant for measurement of hepatitis B surface antibody (anti-HBs), surface antigen and core antibody levels. For those who possessed an anti-HBs antibody < 10 mIU/mL, a single dose of HepB was administered, and 30 days later, serum specimens were collected to assess the booster effects. RESULTS: A total of 1352 participants were included in this study. Of these, 1007 (74.5%) participants could retain an anti-HBs antibody ≥10 mIU/mL, with a geometric mean concentration (GMC) of 57.4 mIU/mL. HBsAg was detected in six participants, resulting in a HBsAg carrier rate of 0.4% (6/1352). Of those participants with anti-HBs antibodies < 10 mIU/mL, after a challenge dose, 231 (93.1%) presented an anti-HBs antibody ≥10 mIU/mL, with a GMC of 368.7 mIU/mL. A significant increase in the anti-HBs positive rate (≥ 10 mIU/mL) after challenge was observed in participants with anti-HBs antibodies between 2.5 and 10 mIU/mL and participants boosted with HepB (CHO), rather than those with anti-HBs antibodies < 2.5 mIU/mL and those boosted with HepB (SC). CONCLUSION: Since satisfactory immune protection against HBV infection conferred by primary vaccination administered 17-20 years ago was demonstrated, there is currently no urgent need for booster immunization.

Investigation of Nonmotor Symptoms in First-Degree Relatives of Patients with Different Clinical Types of Parkinson's Disease.

BACKGROUND: Nonmotor symptoms (NMS) are prodromal characteristics of Parkinson's disease (PD). The first-degree relatives (FDR) of PD patients had a higher risk of PD and also had more NMS. OBJECTIVE: To delineate NMS in FDR of patients with different clinical types of PD. METHODS: A total of 98 PD probands were recruited; 256 siblings of them were enrolled in the FDR group. Various scales were used to assess NMS, including depression, anxiety, cognitive impairment, insomnia, constipation, excessive daytime sleepiness, rapid eye movement sleep behavior disorder (RBD), and restless legs syndrome (RLS). The incidences of NMS were further compared between the FDR groups of PD with different types. RESULTS: The FDR of early-onset PD (EOP) showed a higher incidence of moderate to severe depression (OR = 4.08; 95% CI: 1.12-14.92; P=0.033), anxiety (OR = 4.22; 95% CI: 1.87-9.52; P=0.001), and excessive daytime sleepiness (OR = 3.40; 95% CI: 1.00-11.48; P=0.049) than the FDR of late-onset PD (LOP). It was also found that RBD (OR = 11.65; 95% CI: 3.82-35.54; P < 0.001), constipation (OR = 4.94; 95% CI: 1.85-13.21; P=0.001), sleep disorders (OR = 4.51; 95% CI: 1.73-11.78; P=0.002), cognitive impairment (OR = 3.55; 95% CI: 1.62-7.77; P=0.002), and anxiety (OR = 2.49; 95% CI: 1.32-4.71; P=0.005) were more frequent in FDR of tremor-dominant PD (TDP) than in FDR of non-tremor-dominant PD (NTDP). CONCLUSIONS: The siblings of patients with EOP and TDP have more NMS, presuming that they have a higher risk in the PD prodromal stage. Whether they have a greater possibility to progress into PD requires further investigation.

Comparison of Micro-Clamping Stent-Retriever Thrombectomy with Conventional Stent-Retriever Thrombectomy in Intracranial Large Vessel Embolism.

OBJECTIVE: To evaluate the effectiveness of micro-clamping stent-retriever thrombectomy (MSRT) in patients with acute ischemic stroke with intracranial large vessel embolism (ILVE), and compare it with that of conventional stent-retriever thrombectomy (CSRT). METHODS: We retrospectively evaluated 108 patients with ILVA treated by MSRT (n = 52) or CSRT (n = 56) from the 2 participating institutions between January 2016 and November 2017. The rates of successful (Modified Thrombolysis in Cerebral Infarction [mTICI] grade 2b or 3) and complete reperfusion (mTICI grade 3), time from guide catheter placement to reperfusion, rates of first-pass success, and the number of passes for reperfusion were compared between the MSRT and CSRT groups. RESULTS: The complete reperfusion (mTICI 3) rates by MSRT were significantly higher than those achieved with CSRT (78.8% [41/52] vs. 57.1% [32/56], respectively; P = 0.016). Successful reperfusion (mTICI 2b or 3) rates were 92.3% (48/52) in the MSRT group and 83.9% (47/56) in the CSRT groups (P = 0.181). The mean number of passes for reperfusion was significantly lower with MSRT compared with CSRT (1.5 ± 0.2 vs. 2.5 ± 0.5, respectively; P = 0.001). The first-pass success rates were significantly higher in the MSRT group than in the CSRT group (65.4% [34/52] vs. 28.6% [16/56]; P = 0.0001). The mean time from guide catheter placement to reperfusion was significantly shorter in the MSRT group (20.5 ± 6.6 minutes vs. 46.3 ± 7.6 minutes; P = 0.001). CONCLUSIONS: These findings suggest that the complete reperfusion rates and mechanical thrombectomy efficiency in patients with ILVE are better after MSRT compared with CSRT.

Investigation of non-motor symptoms in first-degree relatives of patients with Parkinson's disease.

OBJECTIVE: Non-motor symptoms (NMS) are important prodromal characteristics of Parkinson's disease (PD). However, the incidence of NMS in first-degree relatives, such as siblings of PD patients, is still unknown. METHODS: A total of 98 PD patients of the Affiliated Hospital of Yangzhou University were recruited; 210 siblings of these patients were included in a first-degree relatives (FDR) group and 250 healthy individuals were included in a control group. Various scales were used to assess NMS, including depression, anxiety, cognitive function, sleep status, constipation, daytime sleepiness, Rapid-Eye-Movement Sleep Behavior Disorder (RBD), and Restless Legs Syndrome (RLS). RESULTS: NMS were more common in the PD group than the control group. The incidence of anxiety (OR = 3.434, 95%CI: 2.058-5.731, P < 0.001), depression (OR = 2.438, 95%CI: 1.289-4.609, P = 0.005), and RBD (OR = 4.120, 95%CI: 1.897-8.945, P < 0.001) was higher in the FDR group than the control group. There were non-significant differences in constipation, cognitive impairment, sleep disorder, daytime sleepiness, and RLS between the two groups. The incidence of RLS in FDR of PD with an age of onset <60 years was higher than in the controls (OR = 2.273, 95%CI: 1.107-4.667, P = 0.023). CONCLUSIONS: Siblings of PD are more likely to suffer from anxiety, depression and RBD than the general population. RLS is more common in siblings of PD with onset age<60 than in the general population. It is speculated that PD patients and their siblings have common pathogenic genetic factors and early living environment for neurodegeneration.

Immune memory at 17-years of follow-up of a single dose of live attenuated hepatitis A vaccine.

BACKGROUND: In recent years, hepatitis A virus (HAV) infection has declined considerably in China, associated with wide deployment of HAV vaccines and improvement in socio-economic indicators. Towards the elimination of HA in the country, we assessed the duration and characteristics of immunity conferred by the widely used, locally manufactured HAV vaccine. METHODS: This is a longitudinal cohort study that followed recipients of a live attenuated HAV vaccine 17 years after the initial administration. Blood samples were collected from participants pre- and two-week post-booster HAV vaccine dose. Serum anti-HAV antibody was measured by ELISA method. Memory B and T cells were determined by ELISPOT and Flow Cytometry assays, respectively. RESULTS: A robust anamnestic response was observed two-week post-challenge. Both HAV-specific memory B cell and T cells remained, and responded quickly when re-encountering HAV. The magnitude of recall responses was present, regardless of the status of the serum anti-HAV antibody pre-booster. CONCLUSIONS: We demonstrated long-term immunity from the live attenuated HAV vaccine, including antibody persistence and immunological memory. Considering the conditions that make elimination of infectious diseases feasible, following polio, hepatitis A could be targeted for elimination in China.

Thrombectomy Using "Clamping Embolus with Semi-Retrieval" Technique in Acute Ischemic Stroke.

BACKGROUND: Embolization of thrombus fragments in new or downstream vascular territories is a potential adverse event in neurothrombectomy, requiring additional repeated thrombectomy attempts. This study aims to describe technical results of the thrombectomy with clamping embolus technique (TCET) method in acute ischemic stroke. This study also aims to evaluate the efficiency of mechanical thrombectomy by TCET, and to compare it with conventional stent retriever thrombectomy (CSRT). MATERIALS AND METHODS: A retrospective analysis was performed in 52 consecutive patients treated between January 2015 and October 2016 for intracranial large vessel occlusion by stent retriever thrombectomy. Recanalization rates, procedure durations, and thrombectomy attempts were compared between the TCET and the CSRT groups. RESULTS: Successful recanalization (thrombolysis in cerebral infarction [TICI] 2b or 3) with TCET was achieved in 91.7% (22 of 24) versus 92.9% (26 of 28) in the CSRT group (P = .921). To preserve the restored patency of severely affected atherosclerotic intracranial vessels, 7 and 8 patients received angioplasty or stenting in the TCET and CSRT groups, respectively. In embolic cases, the number of thrombectomy attempts with TCET was significantly lower than that obtained with CSRT (1.7 ± .2 versus 2.6 ± .5, respectively; P = .001); the one-pass thrombectomy rate was significantly higher in the TCET group than in the CSRT-treated patients (58.8% versus 25.0%, respectively; P = .014). Procedure duration was significantly shorter by TCET than by CSRT (35.8 ± 5.8 minutes versus 55.5 ± 7.2 minutes, respectively; P = .001). CONCLUSIONS: The efficiency of mechanical thrombectomy by TCET in acute ischemic stroke might be improved compared with CSRT.

Blood Oxygenation Level-Dependent Functional Magnetic Resonance Imaging in Early Days: Correlation between Passive Activation and Motor Recovery After Unilateral Striatocapsular Cerebral Infarction.

OBJECTIVE: This study aimed to investigate the correlation between the functional magnetic resonance imaging (fMRI) pattern and the motor function recovery of an affected limb during the passive movement of the affected limb at an early stage of the striatocapsular infarction (SCI). METHODS: A total of 17 patients with an acute stage of SCI and 3 healthy volunteers as controls were included in this study. fMRI scans of passive movement were performed on the affected limbs of stroke patients within 1 week of onset. Follow-ups were carried out for the motor functions of the affected limbs (before fMRI scan, 1 month, and 3 months after the scan). RESULTS: The control group showed that the activation was mainly located in the contralateral sensorimotor cortex (SMC) and the bilateral supplementary motor area (SMA). The fMRI scan region of interest for stroke patients can be divided into 3 types: type I includes mainly the affected side, bilateral SMC, and SMA with activation; type II includes SMC on the affected side and SMA with activation; type III includes only SMC on the affected side or M1 with activation. The recovery of type I patients was better and faster, while the recovery of type II patients was better but slower, but recovery of type III patients was poorer and slower. CONCLUSIONS: Multiple cortical activation patterns were noted during the passive movement of the affected limbs at an early stage of SCI, and a correlation was found between the different activation patterns and the clinical prognosis of patients.

Variation analysis of norovirus among children with diarrhea in rural Hebei Province, north of China.

To understand the distribution of genotyping, as well as evolution of norovirus circulating among children<5yrs., a population-based diarrhea surveillance targeted children<5yrs. was conducted in rural Zhengding County, Hebei Province, China between October 2011 and March 2012. RT-PCR was used to amplify the capsid-encoding region of GI and GII norovirus to identify norovirus infection. All PCR products were sequenced and analyzed for genotyping and constructing phylogenetic tree. Dynamic distribution network was constructed by TempNet to illustrate the genetic relationships at two different time points. Bayesian evolutionary inference techniques were applied by BEAST software to study the norovirus evolution rate. During the 6-month surveillance period, 1091 episodes of diarrhea were reported from 5633 children under 5years of age lived in catchment area. 115 of 1091 stool specimens were detected as norovirus positive (10.54%). Five genotypes based on capsid gene sequences were identified, including GII.2 (11), GII.3 (52), GII.4 (47), GII.6 (4) and GII.7 (1). An identical haplotype of GII.4 circulated between 2006 and 2011 in Hebei Province. A mean rate of 6.29×10-2 nucleotide substitutions/site/year (s/s/y) was obtained for GII.3 viruses in Hebei, while the GII.4 viruses evolved at a mean rate of 3.67×10-2s/s/y. In conclusions, GII.3 (45.22%) and GII. 4(40.87%) are the predominant strain in Hebei Province in the winter season of 2011 and 2012. Different from the current consensus, our study shows that GII.3 noroviruses in Hebei Province evolved at a faster rate than GII.4 viruses.

Effectiveness of the live attenuated rotavirus vaccine produced by a domestic manufacturer in China studied using a population-based case-control design.

A universal rotavirus (RV) immunization program is a potentially cost-effective measure for preventing RV infection in China. However, the efficacy of the only licensed RV vaccine (Lanzhou lamb rotavirus vaccine, LLR), which is made by a domestic manufacturer, has not been proven by a properly designed clinical trial. In October 2011 to March 2012, to measure the potential protection provided by LLR, a case-control study nested in a population-based active diarrhea surveillance study of children <5 years of age was conducted in rural Zhengding county. During the study period, 308 episodes of diarrhea were identified as being caused by RV infection, resulting in an incidence rate of 48.0/1000 people/year. The predominant RV serotype was G3 (61.5%), followed by G1 (15.2%), and G9 (6.5%). Overall, a protection of 35.0% (95% confidence interval (CI), 13.0%-52.0%) was identified, and higher protection was found among moderate RV gastroenteritis cases caused by the serotype G3 (52.0% 95% CI: 2.0%-76.1%). A concurrently conducted case-control study comparing non-RV viral diarrheal cases with non-diarrheal controls in the same population found that the RV vaccine offered no protection against non-RV diarrhea. Even under a less ideal immunization schedule, the oral LLR conferred a certain level of protection against RV gastroenteritis. However, further studies are needed to understand the full characteristics of the LLR, including its efficacy when administered following the optimal regimen, the potential risk of inducing intussusception, and the direct and indirect protective effects of LLR.

Waning of anti-HAV immunity in Shijiazhuang prefecture, Hebei province, China: a comparison of seroprevalence between 1992 and 2011.

OBJECTIVE: To study the epidemiological patterns of hepatitis A, and immunity of entire population in Shijiazhuang prefecture, Hebei province, a former hyper-endemic area in north China. METHODS: Cross-sectional, seroprevalence surveys with two-stage cluster sampling were conducted among population older than 2-year between 1992 and 2011. During the 2011 serological survey, blood samples from infants <18 months without hepatitis A immunization history were also collected to determine maternal anti-HAV antibody. Serum samples were tested for anti-HAV antibody by domestic reagent or Abbott reagent. Viral hepatitis incidence rates and gross domestic product data were derived from local governmental statistics. RESULTS: Concomitant with the reduction of reported hepatitis A cases between 1992 and 1996 was a significant decline of HAV infections. The average prevalence decreased from 93.6% to 41.9%, and the average age at new infection was postponed from infancy to adolescence. This was attributed to improved socio-economic conditions. With intensive vaccination, a return of new seroconversion rate and seroprevalence was observed. A well fitted exponential regression equation (R(2)=0.96, p<0.0001) modeled that the maternal antibody would wane to <20 mIU/mL at 13 months. CONCLUSION: Benefiting from the booming economy, rapid improvement in sanitation, safe water supply, and implementation of hepatitis A vaccines, the epidemiological pattern of hepatitis A moved from high to intermediate endemicity in Shijiazhuang. Policy makers should be aware of the waning of immunity in entire population, and adapt immunization strategy timely, to ensure a lifelong protection against hepatitis A virus.

[12 years immunological effects of hepatitis B vaccine made by recombinant deoxyribonucleic acid techniques in Chinese hamster ovary cell].

OBJECTIVE: To understand the long-term immunological effects of a recombined hepatitis B vaccine [HepB made by recombinant deoxyribonucleic acid (DNA) techniques in Chinese hamster ovary (CHO) cell, HepB (CHO)]. METHOD: from 1997 to 1999 all newborns in Zhengding County were administered to HepB (CHO)at birth. Children in 3 of all 7 towns in the county were selected as study objects to check their hepatitis B vaccination history and test for HBV markers. RESULTS: Children who aged 10, 11 and 12 years after immunization, the anti-HBs positive rates were 71.0%, 72.1% and 68.2% respectively, and the geometric mean concentration (GMCs)were 197.9 mIU/ml, 296.0 mIU/ml and 158.0 mIU/ml respectively; Anti-HBs GMCs were 197.9 mIU/ml, 296.0 mIU/ml and 158.0 mIU/ml respectively. The Average GMC was 207.9 mIU/ml. HBsAg and anti-HBc positive rates were 0.50% and 2.26% respectively. CONCLUSION: The long-term immunological effects of HepB (CHO) are excellent.

[Comparison of antibody persistence between live attenuated and inactivated hepatitis A vaccines].

OBJECTIVE: To study the antibody persistence of live attenuated hepatitits A vaccine, and to compare the antibody between with inactivated vaccine. METHODS: 211 HAV susceptible children were divided randomly into three groups, Group A was injected three doses HepA-L at 0, 6 and 12 monthes; Group B was administrated two dose HepA-L at 0 and 6 months, and group C was immunized with inactivated vaccine at month 0 and 6. Serum samples were detected for Anti-HAV at 1, 6, 7, 12, 13, 24, 84 months after vaccination in each group. RESULTS: The seroconversion rates reached 100% after 2nd dose in all groups. The highest GMC was 2938.1 mlU/ml, founded in group C, and it was 1315.6 mlU/ml and 1586 mlU/ml in group A and B respectively. After the 3rd dose at month 12 in group A, the antibody increased dramatic, which reached 1945.3 mlU/ml. 84 months after first dose in each group, the antibody can be detected from all subjects. Though the GMC in group A declined to 336.8 mlU/ml, it was significant higher than that in group B and C. CONCLUSION: The good booster effect with HepA-L was well observed in a short-term. The immune response induced by 2 to 3 doses HepA-L could compete with inactivated hepatitis A vaccine. However, long-term effects of both vaccines need further study.

[The immunological effects of three doses of a live attenuated hepatitis A vaccine (H2 strain) in 8 years].

OBJECTIVE: To observe the immunological effects of three doses of H2 strain live attenuated hepatitis A vaccine 8 years after the administration and to compare with that of one dose of the vaccine. METHODS: In a country area, 110 children of 1 to 7 years old susceptible to HAV were screened and administered with one dose of the vaccine, as group B; Group A were 42 children from one of the villages and administered with 3 doses of the vaccine according to 0, 2, 6 month schedule. Blood samples were taken for the children 1, 2, 6, 7, 8, 12, 24, 36 and 96 months after the administrations respectively and detected for anti-HAV antibody. RESULTS: For group B, the sero conversion rate of anti-HAV and GMC reached peak at 92.2% and 126.2 mIU/ml respectively, and then, began to drop with time; For group A, after 2 dose of the vaccine, the sero-conversion rate reached 100%, and the GMC reached peak of 2 739 mIU/ml one month after the third dose at 7 months. So that, group A has a better short-term immunological effects than that of group B. During 36 through 96 months, the anti-HAV positive rate in group B was 75%-71% and 80-89 mIU/ml respectively, and comparatively in group A were 100% and 918.2-480.6 mIU/ml respectively. The differences between group A and B were significantly important. CONCLUSION: A 3-dose schedule administration of H2 strain live attenuated hepatitis A vaccine has better immunological effects than 1-dose schedule in 8years and further observations are needed.

A follow-up study of mortality among the arseniasis patients exposed to indoor combustion of high arsenic coal in Southwest Guizhou Autonomous Prefecture, China.

OBJECTIVE: This study was directed to ascertain the mortality of a group of arseniasis patients in an endemic rural township in Southwest China, where the residents were exposed for decades to indoor combustion of high arsenic coal. METHODS: All the diagnosed arseniasis cases registered in 1991 were defined as the target population, which were assigned to three symptom subgroups by the severity of dermal lesions. The death cases were surveyed and checked. The follow-up period was 12.5 years. The standardized mortality ratio (SMR) of all death causes combined, all cancers combined, and the cancers at every site were analyzed. The age standardized mortality rates (ASMRs) were calculated in three subgroups using the procedure of standardization. RESULTS: One hundred and six death cases were recorded. Liver cirrhosis, non-melanotic skin cancer, lung and liver cancer were the four most prevalent death causes and referred to 70.8% (75/106) of the total death cases. The mortality of all death causes combined was not higher than that of the whole of China in 2001 (SMR = 0.76, 95% CI 0.63-0.93). The crude mortality rate of non-melanotic skin cancer in males reached up to 128.66/10(5). SMRs of lung cancer and larynx cancer in males (SMRs 2.84 and 27.27, 95% CIs 1.51-4.86 and 5.61-79.62, respectively) significantly exceeded the levels for all male Chinese. ASMRs of all death causes combined, all cancers combined and non-melanotic skin cancer in males of the severe dermal symptoms subgroup were significantly higher than those in medium and/or mild dermal symptom subgroups. CONCLUSIONS: A significantly increased mortality due to lung cancer and non-melanotic skin cancer was confirmed, alike the situation in other arseniasis endemic areas in the world. No significant elevation of mortality due to liver cancer and bladder cancer was observed. Male arseniasis patients diagnosed with severe skin lesions face higher risks of malignancies and of non-melanotic skin cancer in particular in the following years.