Effect of TLR gene polymorphisms on primary immune response to hepatitis B vaccine in Han children of Guangxi / 中华疾病控制杂志

Objective To explore the association between Toll-like receptors(TLR) gene polymorphisms and the primary immune response level to Hepatitis B Vaccine in Han children in Guangxi. Methods A total of 513 Han children aged 8-9 months were collected from the department of pediatrics in the Maternal and Child Hospital of Guangxi Zhuang Autonomous Region and Nanning Maternal and Child Health Hospital from 2014 to 2016. Peripheral venous blood of each study object was collected to detect HBsAg, anti-HBs, HBeAg, anti-HBe, anti-HBc and HBV DNA. The polymorphisms of 10 sites of TLR gene were detected by SNPscanTM multiple SNP typing techniques. The association between allele, genotype of TLR gene and anti-HBs levels were analyzed by non-conditional logistic regression. Results The genetic polymorphism of TLR3 gene rs13126816 was related to immune response after primary Hepatitis B immunization in Han children in Guangxi (OR=1.79，95% CI: 1.11-2.89, P=0.018). The anti-HBs level of children with A/A genotype［238.04(519.75) mIU/L］and G/A genotype［347.96(619.68) mIU/L］were significantly lower than those with G/G genotype［489.08(854.76) mIU/L］, and the differences were statistically significant (all P0.05). Conclusions The allele A of TLR3 gene rs13126816 may be the influencing factor for the low response of primary immune response to Hepatitis B Vaccine in Han children.

On-site assessment on the definition and classification of suspected cases in the manual of WHO Japanese Encephalitis Surveillance Standards / 中华流行病学杂志

Objective To assess the new edition of WHO Japanese Encephalitis (JE) Surveillance Standards (WHO Standards) based on syndrome surveillance data and to provide field evidence regarding the standards. Methods Based on syndrome surveillance data, acute encephalitis syndrome (AES) case was categorized, according to the WHO Standards. A cohort study was applied to estimate the AES definition set in the Standard and relative risk was computed to estimate the existence and intensity of statistical correlation between AES and JE cases. Percentage of attributable risk was counted to describe the coverage of AES for JE cases in the studied population. Sensitivity,specificity, Youden index and positive predictive value of AES components were calculated for the purpose of identifying the clinical values under the screening program. Results 1424 suspected cases were evaluated in the surveillance program and 1396 cases with ELISA result, of which 109 positive cases were detected. According to the "standardized" classification, a total of 706 cases in line with AES case deftuition, were categorized into 83 cases of JE, 425 cases of AES unknown and 198 cases of AES other agent. In the cohort study,a relative risk of 4.62 (95% CI:2.80-7.63 ) and the percentage of attributable risk as 78.35% (95% CI: 64.25% -86.89% ) were observed. Conclusion The AES definition for JE was significantly effecting on the screening programs and a strong correlation strength was observed in the study. AES syndrome could cover most of the JE cases. "Convulsions",with appreciative screening value, was recommended to be involved into the new version of the WHO Standards.

Surveillance and research on acute meningitis, encephalitis syndrome in Guangxi, China / 中华预防医学杂志

<p><b>OBJECTIVE</b>To estimate disease burden and epidemiological characteristics of acute meningitis/encephalitis, and provide the basis for the disease control strategy development.</p><p><b>METHODS</b>A syndrome surveillance system was established in Guigang city with a population of 5 020 000. For the suspected cases, serum and CSF were collected, and bacterial culture, latex agglutination test, real-time PCR and ELISA tests were carried out. All involved cases were identified to 6 categories according to WHO case definition.</p><p><b>RESULTS</b>1424 suspected cases were evaluated in a surveillance of 30 months, yielding the incidence, mortality and mortality of 11.35/100 000 (1424/12 546 500 person years), 0.43/100 000 (54/12 546 500 person years), 3.79% (54/1424) respectively. A total of 103 and 51 cases were confirmed for JE, bacterial meningitis, with a incidence of 0.82/100 000 (103/12 546 500 person years), 0.41/100 000 (51/12 546 500 person years). 96.10% (99/103) of JE cases and 37.30% (19/51) bacterial meningitis cases occurred in < 10 years old children and < 5 years old children. A clinical misdiagnosis rate of 19.42% (20/103) and 15.69% (8/51) were observed for JE and bacterial meningitis.</p><p><b>CONCLUSION</b>Acute encephalitis, meningitis syndrome can cause a higher burden of disease, of which the main components of viral encephalitis. Most of syndrome is occurred in summer and autumn, mainly reported in children of younger than 10 years old. A quite misdiagnosis would be made among meningitis and encephalitis syndrome cases.</p>

Comparative analysis of three diarrhea-household-surveys in Guangxi / 中华流行病学杂志

Objective To study the epidemiological characteristics and the effects of control measurements in Guangxi by comparing the results from diarrhea-household-surveys conducted in the three different periods of time and to develop control strategies. Methods Data on the incidence, health care seeking and treatment of diarrhea from three household surveys conducted in 1988, 1995 and 2007 was analyzed using SPSS (version 13.0). Results The incidence rates of diarrhea over the three periods of time were 0.562, 0.456 and 0.221 per person-year, respectively (P<0.001). No significant difference was found in the incidence between males and females. The disease mainly attacked young age groups and those with lower educational levels. In recent years, longer durations of disease but less severe were observed in patients with diarrhea. The patients mainly visited first line health services with a health care seeking rate of 28.3%. Antibiotics were used by most of the patients (49.8%-90.2%), while the rate of using oral rehydrathon salts(ORS) was only 1.4%-11.5% but the use of traditional Chinese medicines has increased. Intake of untreated water, contaminated foods and contact with patients were important risk factors on diarrhea. Conclusion The prevalence of diarrhea in Guangxi had declined and the health seeking rate was low in the past two decades. It is necessary to further regulate the treatment, in order to strengthen the health education programs to the general population, in order to improve the accessibility of health services and to increase both the health care seeking rate and effective diagnosis rate.

A prospective study of the relationship between serum hepatitis B virus DNA and the risk of primary liver cancer / 中华肝脏病杂志

<p><b>OBJECTIVE</b>To determine the relationship between the serum hepatitis B virus (HBV) DNA and the risk of primary liver cancer (PLC).</p><p><b>METHODS</b>Farmers aged 30 to 55 years in Long An county were recruited in this study Blood samples were collected and the sera were tested for HBsAg using Enzyme-Linked ImmunoSorbent Assay (ELISA), and the HBsAg-positive sera were further tested for viral DNA using nested polymerase chain reaction (nPCR). The study subjects were divided into three groups. The first group was positive for both HBsAg and HBV DNA. The second group was positive for HBsAg but negative for HBV DNA. Age-, sex-, residence-matched HBsAg negative controls for group 1 and group 2 were enrolled in the third group. The cohort was followed up for four years.</p><p><b>RESULTS</b>The positive rate of HBsAg in these farmers was 14.52% (3975/27,379), and the HBV DNA positive rate in HBsAg positive subjects was 40.35% (1604/3975). The total PLC incidence rate in Group 1 and 2 was 672.45 /100,000 person-years (PY), significantly higher than that in Group3 (17.19 /100,000 PY). The relative risk (RR) was 39.123, and the 95% confidence interval (CI) was 9.018-159.146. The PLC incidence rate of Group 1 (984.03/100,000 PY) was significantly higher than that of Group2 (324.38 /100,000 PY). The RR was 3.034, and the 95% CI was 1.795-5.125. Multivariate analyses of Group1 and 2 with Cox model showed that sex, age, serum HBV DNA, and family history of PLC were independent risk factors of PLC.</p><p><b>CONCLUSION</b>HBV DNA and HBsAg positive subjects have a higher chance to develop PLC than HBV DNA negative-, HBsAg positive subjects.</p>

Effectiveness of an immunization campaign with group A and C meningococcal polysaccharide vaccine in controlling an outbreak of group C meningococcal disease / 中华流行病学杂志

Objective To assess the safety, immunogenicity and efficacy of group A and C meningococcal polysaccharide vaccine (A/C MPV) in response to an outbreak of group C meningococcal disease. Methods A vaccination campaign with A/C MPV was prompted 6 weeks after the use of group A MPV in Laibin city, Guangxi, where an outbreak of group C meningococcal meningitis occurred in 2002.Vaccinees were observed for local and systemic reactions after the vaccination and followed up for the meningococcal disease for 5 years. Blood samples were collected from 71 people in the epidemic and 43 in the non-epidemic areas before and 1 month after the vaccination and examined by ELISA to detect IgG antibodies to group A and C polysaccharides. Results The vaccination coverage was 97%. No significant adverse reactions were observed. The positive rates of group C antibodies after vaccination was between 97.67% and 100% among the populations in the epidemic and non-epidemic areas, as well as among those negative and positive for group C antibodies prior to the vaccination.The geometric mean anti-C concentrations ranged 30.81 μg/ml to 37.44 μg/ml, showing no significant difference between groups. The incidence rate of meningococcal disease in students with timely immunization (218.58/100 000) dropped by 69.02% , when compared to that in those with delayed immunization (705.72/100 000). No clinical cases were identified during the follow-up period of 15 760 person-years. Conclusion The vaccination campaign with the Chinese group A/C MPV seemed successful in controlling the group C meningococcal outbreak.The vaccine was shown to be safe even administered after the group A vaccine only 6 weeks apart. It could induce high levels of antibodies in vulnerable population and significantly increase antibody levels in seropositive individuals, thus providing a protection of at least 5 years.

Evaluation on the safety of a group A + C meningococcal polysaccharide vaccine / 中华流行病学杂志

<p><b>OBJECTIVE</b>To evaluate the safety of a group A + C meningococcal polysaccharide vaccine as part of a phase IV clinical trial.</p><p><b>METHODS</b>The study area was divided into 108 clusters according to the principle of cluster randomization, stratified and paired sampling methods. 54 out of 108 clusters served as observation groups were administered A + C vaccine, while the rest 54 groups were administered Vi polysaccharide vaccine. An adverse event surveillance system was established to monitor the adverse events following the vaccination campaign. Identical form and methods were used for data collection to investigate the adverse events following the vaccination of both A+ C vaccine and Vi vaccine.</p><p><b>RESULTS</b>34,543 people were vaccinated, including 18,167 of whom received A + C vaccine, while the other 16,376 received Vi vaccine. The rates of immediate injection reaction and unsolicited non-serious adverse events from A + C vaccine group were 0.44% and 0.38% while of Vi vaccine group were 0.79% and 0.73% respectively. At the solicited adverse event survey on 3-day-post-vaccination, 1239 vaccinees were followed-up including 771 received A + C vaccine and 468 received Vi vaccine. The local injection reaction rate of A + C vaccine group on the 1st day was significantly higher (X2 = 13.98, P = 0.0002) than that of Vi vaccine group. Neither the local injection reaction rate nor the system reaction rate between both groups was significantly different on 2nd and 3rd day, post vaccination. It was not statistically different when comparing fever onset rate between those who received vaccine and those who did not, in each vaccine group. There were no serious adverse events observed.</p><p><b>CONCLUSION</b>Results showed that the side effects of A + C vaccine and the Vi vaccine were mild and safe for vaccination campaigns targeting on populations at different age.</p>

Application of cluster randomization method on typhoid Vi vaccine trails / 中华流行病学杂志

<p><b>OBJECTIVE</b>To describe the design and application of cluster randomized controlled method on typhoid Vi vaccine trial, and to assess the effect of implementation.</p><p><b>METHODS</b>Simple size calculation of cluster-randomized trial was used to determine the sample size of the two groups and a vaccination campaign was conducted. The study group was given typhoid Vi vaccine and the control group was given meningococcal A vaccine.</p><p><b>RESULTS</b>According to sample size calculation, a total sample of 96,121 participants was required and the study areas were divided into 108 clusters. In practice, 53 study clusters with 44,054 participants and 54 control clusters with 48,422 participants were stratified and matched according to size, location (urban or rural), characteristics (school, department, factory, demography) were randomized respectively. Confounding factors of two groups including age, sex, resident area, income, level of education were compared. It was found that the ratio of all confounding factors between the two groups were comparable and balanced.</p><p><b>CONCLUSION</b>Confounding factors can be better controlled between study group and the control group by applying cluster-randomized method on vaccine trail which enabled the intervention to be more scientifically evaluated; The implementation of cluster randomization trial was simple and easy to be accepted.</p>

Epidemiologic surveillance for bacterial meningitis in 140 000 children under 5 years of age in Nanning district, Guangxi province / 中华流行病学杂志

<p><b>OBJECTIVE</b>To characterize the incidence, epidemiologic features, etiologic agents and sequelae of bacterial meningitis in children under 5 years of age in Nanning, Guangxi.</p><p><b>METHODS</b>A population-based surveillance was conducted to evaluate children with signs and symptoms of meningitis. All hospitals, township health centers and village clinics in the surveillance area were structured to participate in the case referral and evaluation. Cerebrospinal fluid (CSF) and blood specimens were obtained and processed using standardized microbiologic methods.</p><p><b>RESULTS</b>During the 26-month surveillance period, among the children under 5 years old, a total of 1272 cases who met the screening criteria of meningitis were studied. 265 of 1272 cases were identified as clinically diagnosed meningitis, with an incidence rate of 86.36 per 100 000 population. The annual incidence rate under the 38 cases of confirmed bacterial meningitis appeared to be 12.38/100 000. Staphylococcus species accounted for the largest proportion of laboratory-confirmed bacterial meningitis, followed by E. coli and S. pneumoniae. The highest attack rate occurred in neonates < 1 month, followed by children aged 1 - 12 months in the confirmed patients. Meningitis caused by Sp and Hi mainly occurred in children aged 1 - 12 months. All cases of meningitis due to Hi and Sp were children aged 1 - 24 months. 13.16% and 0.00% of the cases survived with complications and sequelae, and the case-fatality rate was 18.42%. 40 bacterial isolates were identified from 1193 blood cultures and 23 from 1211 cerebrospinal fluid samples, but no Neisseria meningitidis was found.</p><p><b>CONCLUSION</b>Meningitis due to Hi was first confirmed in Guangxi with the incidence of 0.98 per 100 000 population. The annual incidence rate of confirmed bacterial meningitis was 12.38 per 100 000, which was considered an important public health problem in children. Staphylococci was the predominant pathogen in confirmed bacterial meningitis.</p>

A study on early detection for seven infectious diseases / 中华流行病学杂志

<p><b>OBJECTIVE</b>To provide methods and alert thresholds which are scientific, sensitive, specific and practical for Early Warning System in Public Health Surveillance.</p><p><b>METHODS</b>Alert data was based on historical infectious diseases reports. Control chart was used to detect outbreaks or epidemics. An epidemic was defined by consulting Specialists. After calculating sensitivity, specificity, positive predictive value and describing receiver-operating characteristic curve (ROC), the optimal model and thresholds were chosen.</p><p><b>RESULTS</b>At 80 percentile, the sensitivities and the specificities of epidemic haemorragia fever, hepatitis A, dysentery, epidemic cerebrospinal meningitis and malaria were over 90%, and there was a high efficacy of early warning. At 90 percentile, the sensitivities and the specificities of tuberculosis and measles were over 85%, and there was a high efficacy of early warning also.</p><p><b>CONCLUSION</b>Control chart based on five years was chose as a essential method in early warning system. The alert threshold for epidemic haemorragia fever, hepatitis A, dysentery, epidemic cerebrospinal meningitis and malaria was 80 percentile. The alert threshold for tuberculosis and measles was 90 percentile.</p>