Evaluating the real-world vaccine effectiveness using a regression discontinuity design / 中华流行病学杂志

Estimating the actual real-world effectiveness of the vaccine is an essential part of the post-marketing evaluation. This regression discontinuity design (RDD) using observational data is designed to quantify the effect of an intervention when eligibility for the intervention is based on a defined cutoff as age, making it suited to estimate vaccine effects. This approach can avoid the high cost and ethical issues; overcome difficulties in the organization and practice process in randomized controlled trials, which leads to a higher level of causal inference evidence and more realistic results. Here, we describe key features of RDD in general, and then specific scenarios, with examples, to illustrate that RDD are an essential tool for advancing our understanding of vaccine effects.

Advances in research of interchangeable immunization with live attenuated Japanese encephalitis vaccines and inactivated vaccines / 中华预防医学杂志

Japanese encephalitis (JE) virus is the leading cause of vaccine-preventable encephalitis in Asia and the Western Pacific, which mainly invades central nervous system. Vaccination is the most important strategy to prevent JE. Currently, both live attenuated Japanese encephalitis vaccines (JE-L) and inactivated vaccines (JE-I) are in use. Due to the supply of vaccines and the personal choice of recipients, there will be a demand for interchangeable immunization of these two vaccines. However, relevant research is limited. By reviewing domestic and foreign research evidence, this article summarizes the current situation of the interchangeable use of JE-L and JE-I, and makes recommendations when the interchangeable immunization is in urgent need, so as to provide reference for practical vaccination and policymaking in China.

Epidemiological characteristics and spatiotemporal clustering of hepatitis A in Zhejiang Province from 2010 to 2019 / 中华预防医学杂志

Objective: To analyze the epidemiological characteristics and spatiotemporal clustering of hepatitis A in Zhejiang Province from 2010 to 2019. Methods: The data of hepatitis A incidence in Zhejiang Province from 2010 to 2019 were collected from the infectious disease surveillance system of China Information System for Disease Control and Prevention. ArcGIS 10.7 software was used for spatial autocorrelation analysis. SaTScan 9.6 software was used for spatiotemporal scanning analysis. SPSS 25.0 software was used for additional analysis. Results: Zhejiang Province has reported 5 465 cases of hepatitis A in 2010-2019 years, with an average annual incidence rate of 1.00/100 000, and periodicity and seasonality are not obvious. The incidence of male was higher than that of female (P=0.023), and the highest incidence rate was 50-59 years old. Spatial autocorrelation analysis showed that there was a positive spatial correlation between the incidence of hepatitis A in Zhejiang Province from 2010 to 2017, with the weakest correlation in 2010 (Moran's I =0.103, Z=1.769, P=0.049), and the strongest correlation in 2016 (Moran's I=0.328, Z=4.979, P=0.001). Spatiotemporal scanning analysis showed that there was spatial aggregation of hepatitis A in Zhejiang Province from 2010 to 2019, with a total of three aggregation areas identified. Among them, the mostly aggregation area was concentrated in Xiangshan county of Ningbo city, which covered 10 counties (cities and districts), including Ninghai county and Yinzhou district, and appeared from January 1 to June 30, 2012. Conclusion: The incidence level of hepatitis A in Zhejiang Province shows a stable fluctuation trend from 2010 to 2019, and the seasonal regularity is not obvious. The population group aged 50-59 years old is the key population. There is spatial aggregation in the epidemic situation of hepatitis A. Targeted prevention and control measures of hepatitis A should be done based on the law of spatiotemporal aggregation and local incidence.

Consideration on implementation of co-administration of Seasonal Influenza and COVID-19 vaccines during pandemic in China / 中华预防医学杂志

Influenza is an infectious respiratory disease caused by the influenza viruses. Older people, infants and people with underlying medical conditions could have a higher risk of severe influenza symptoms and complications. The co-infection of Coronavirus Diseases 2019 (COVID-19) with influenza viruses could lead to the complication of prevention, diagnosis, control, treatment, and recovery of COVID-19. Influenza vaccine and COVID-19 vaccine overlapped in target populations, vaccination time, and inoculation units. Although there was insufficient evidence on the immunogenicity and safety of co-administration of influenza vaccine and COVID-19 vaccine, World Health Organization and some countries recommended co-administration of inactivated influenza vaccine and COVID-19 vaccine. This review summarized domestic and international vaccination policies and research progress, and put forward corresponding suggestions in order to provide scientific support for the formulation of vaccination strategy on seasonal influenza vaccine and COVID-19 vaccine.

Economic evaluation on new strategy for preventing poliomyelitis in Zhejiang Province / 预防医学

Objective To evaluate the economic effect of new strategy for preventing poliomyelitis in Zhejiang Province. Methods Based on the population of Zhejiang Province in 2016, cost-effectiveness ratio (CER) , benefit-cost ratio (BCR), and net benefit (NB) were applied to calculate the health economic difference for the new strategy and the original strategy as compared to no vaccination strategy. Univariate sensitivity analysis was used to assess the robustness of results with main parameters; including burdens of poliomyelitis, cost of vaccines, and the vaccination program itself, and the discount rate. Results CERdisease, CERdeath, BCR and NB for the new strategy were 1:52700 RMB Yuan per case, 1:1813700 RMB Yuan per case, 12.26 and 796.6622 million and CERdisease, CERdeath, BCR and NB for the original strategy were 1 :32900 RMB Yuan per case, 1 :1133900 RMB Yuan per case, 19.58 and 823.1753 million, respectively. The results of the univariate sensitivity analysis with main parameters were robust. Conclusion The new strategy for preventing poliomyelitis is necessary for this period of the global polio eradication. Though the new strategy appears not as good as the original strategy on economic evaluation, its health economic benefit is significant.

An analysis on epidemiological characteristics of Japanese encephalitis in Zhejiang Province / 预防医学

Objective To analyze the epidemiological characteristics of Japanese encephalitis (JE) in Zhejiang Province from 2007 to 2016 for developing the measures of control and prevention. Methods The data were collected from national notifiable diseases registry system (NNDRS) and case-based JE surveillance system (JESS) from 2007 to 2016, and they were analyzed through descriptive epidemiological method and Microsoft Office Excel 2010. Results From 2007 to 2016, a total of 595 JE cases were reported in Zhejiang Province, with an average annual incidence of 0.114 per 100000 population, among which, 559 (93.95%) were laboratory confirmed. During the ten years, 20 cases died and the average annual case fatality rate was 3.36% . Cases were distributed mainly in Wenzhou, Ningbo and Taizhou Cities, which accounting for 54.79% of the total.The peak months were July, accounting for 86.89% of all the cases.And 85.71% of all the cases were in the age of 0-14 years and 47.73% were scattered children.And 22.77% of the JE cases were vaccinated but 14.01% of them did not complete the whole course.And 77.23% of the cases did not have the experience of vaccination or unknown.Conclusion The incidence of JE is decreasing. The occurrence of JE is sporadic with distinct seasonal peak and mainly concentrating in young-age children.

An analysis on the hepatitis B report data from a pilot surveillance in Zhejiang Province / 预防医学

Objective To evaluate the quality of the hepatitis B report data on a pilot surveillance in Zhejiang Province from 2013 to 2015.Methods Hepatitis B report data of 6 pilots in Zhejiang Province from 2013 to 2015 were extracted from national notifiable infectious disease reporting system,including reported cases of hepatitis B,classification of hepatitis B cases and supplementary card information etc. To evaluate the accuracy of hepatitis B classification,information of supplementary cards was used to make classification diagnose for hepatitis B.Results A total of 3214 hepatitis B cases were reported in 6 pilot surveillance counties in Zhejiang Province between 2013 and 2015. Excluded 32 duplicated cases within the year and between years,3182 hepatitis B cases were actually reported,hepatitis B cases repeated reporting rate was 1%. A total of 2717 hepatitis B cases were correctly classified,and the accuracy rate of classification was 85.39%,showing an increasing trend (P<0.05). The proportion of accurate classification of reported hepatitis B by referring to the results of positive time of HBsAg and ALT from the supplementary card were 80.86% and 97.29% respectively. Among those reported acute hepatitis B cases,90.43% of them filled with anti-HBc IgM positive in supplementary card. The proportion of accurate classification of reported hepatitis B by referring to the information for liver puncture and the HBsAg and anti-HBs transform during the recovery period in supplementary cards were 0.19% and 5.13% respectively. Among those reported acute hepatitis B cases,0.69% of them were chronic or undetermined. Among those reported chronic hepatitis B cases,13.92% of them were acute,undetermined or HPV carrier. Five out of 3182 cases were unclassified,accounting for 0.16%.Conclusion The quality of classification diagnosis for hepatitis B should be improved in Zhejiang Province. Filling in the supplementary card is very beneficial for the classification of hepatitis B.

A study on the immunization status of the left-behind children in the rural areas of Zhejiang Province / 预防医学

Objective To investigate the immunization status of the left-behind/non-left-behind children in the rural areas of Zhejiang Province. Methods Multi-stage cluster random sampling was adopted to recruit 0-6 years old children and their guardians in a rural mountainous county in Lishui District of Zhejiang Province. Household survey was conducted using structured questionnaires. Records of vaccination were obtained and verified in the local disease control and prevention center. Results A total of 420 questionnaires were issued, with a number of 416 were complete and valid. The Valid responsive rate was 99.05% . Among them, 97 were left-behind and 319 were non-left-behind children. The immunization coverage rates did not differ significantly between the left-behind and non-left-behind children. The timely immunization rates of the third shot of hepatitis B vaccine and the first shot of encephalitis vaccine differed significantly between left-and non left-behind children (P=0.049 and P=0.044, respectively) . Conclusion Immunization status of the left-behind children in the rural areas of Zhejiang province was in a good condition in general. The local disease control and prevention center should strengthen the communication, to promote immunization knowledge and to improve family supervision of the left-behind children.

A study on status and standards of human resources of vaccination clinics in Zhejiang Province / 预防医学

Objective To learn the status of human resources of vaccination clinics in Zhejiang province and to give suggestions for optimizing the allocation.Methods Investigation and the focus group interview were conducted in Zhejiang Province to learn the configuration standards in vaccination clinics.Results The mean number who attended the immunization work every vaccination day in those clinics was five.The number of staff in each clinic differed from county to county but all reached 0.9 persons serving for 10,000 residents.There should not be less than four persons in each vaccination clinic theoretically.It should be necessary to increase one vaccination staff in every 50 injection doses of vaccine workload.Conclusion The staff of vaccination clinics is inadequate and unbalanced in Zhejiang Province.We should increase staff numbers according to workload and served population.

Self-controlled case-series (SCCS) method as a tool for the evaluation on the safety of vaccine / 中华流行病学杂志

Safety on vaccine issues has been under greater concern.Epidemiologically,classical study designs on investigating the association between a rare adverse event and vaccine inoculation usually confronted with lower feasibility in practice.Self-controlled case series (SCCS) method was derived from cohort studies.The key advantage of this method is that it only uses data related to cases and trying to find relative incidence of events in the ‘ at risk' periods relative to the ‘ controlled' periods.A further benefit of this method is that all the fixed confounders are controlled implicitly,by self-control,thus provides high statistic powers.With these advantages,SCCS is suitable for the causality assessment on rare but severe adverse events caused by immunization,which has been widely used,abroad.However,the methodology of SCCS is still being developed,and the areas in use have been expanded to the studies related to the safety and effectiveness of drugs,efficacy of vaccines as well as risk factors of disease.

Epidemiological effects of the A(H1N1)influenza vaccine immunization program on students / 中华流行病学杂志

Objective To evaluate the epidemiological effects of vaccine immunization program related to A(H1N1)influenza in the middle school students.Methods Non-randomized clinical trial was designed to assess the A(H1N1)influenza vaccine on its efficacy.14883 students from 8 middle schools in Zhejiang province were recruited and classified into vaccinated or control groups,based on the status of immunization with A(H1N1)influenza vaccine.All subjects were followed up through one epidemic period(6 months)and the incidence rates of influenza-like illnesses,A(H1N1)influenza,and seasonal influenza in these two groups were compared to evaluate the efficacy of the vaccine.Results There were 6334 subjects in the vaccinated group and 8549 in the control group.7441.75 person-years were followed from these two groups.The incidence rate of A (H1N1)influenza in vaccinated group was 1.64‰ per person-year,lower than that of the control group.The rate difference(RD)was-1.64‰ per person-year(95% confidence interval value from-3.04‰ to-0.23‰ per person-year),and the difference was significant(P=0.010).The incidence rate of influenza-like illnesses in vaccinated group was 21.47‰ per person-year,lower than that of the control group(22.69‰ per person-year)and the diffefence was not significant(P>0.05).The incidence rate of B influenza in vaccinated group was 6.63‰ per person-year,higher than that of control group(7.02‰ per person-year)but the difference was not significant(P>0.05).Conclusion This vaccine demonstrated a good epidemiological effect against the A(H1N1)influenza virus infection,observed through a student-immunization program.The cross-protection effect against the influenza-like illnesses and other seasonal influenzas was not noticed in this study.

An outbreak of measles among unvaccinated migrant population in Zhejiang province, from June to August, 2010 / 中华流行病学杂志

Objective On July 6, 2010, the parents of a patient with confirmed measles reported several suspected measles patients with fever and rash in their village. An investigation was carried out to verify and understand the cause of the outbreak. Methods Several suspected cases had an onset of fever and rash in this and other neighboring villages during June 1 to August 3,2010. A confirmed case was a suspected case with measles-specific IgM identified in the serum. We conducted door-to-door visits and searched the Chinese Center for Disease Control and Prevention Information System to identify cases, also conducted a retrospective cohort study among migrant children aged 8 months-14 years to identify risk factors related to measles. Results We identified 19 measles cases (17 confirmed case, 2 suspected cases)in the village, and all of them were migrants. Children aged 1-2 years had the highest attack rate(13%). The primary case-patient had onset on the day she arrived in this village(June 4,2010). Caretakers from an unlicensed private clinic were providing service in the village but did not report the outbreak to the public health authority. The outbreak was identified only after receiving a report from the parents of one of the patients, by that time the outbreak had lasted for one month. The measles vaccine coverage rate was 81% among the 315 migrant children aged 8 months-14 years. Among the 61 unvaccinated children, those who reportedly being contacted a measles patient had a higher attack rate(14/16, 88%)than those who did not(2/45, 4.4%)(Relative risk=20, Fisher' s exact 95% confidence interval: 5.7-94). Conclusion The low measles vaccine coverage among migrant children and lack of measures taken on the incident, timely isolation diagnosis/reporting by the caretakers from the unlicensed private clinic etc. had contributed to this prolonged outbreak. Measures need to be taken to improve the immunization services for migrant populations and to enhance measles surveillance programs in the area.

Application of Monte Carlo Techniques in designing compensatory scheme of new cooperative medical system / 中华流行病学杂志

[Introduction] To design a workable compensatory scheme of new cooperative medical system (NCMS) in rural China, 'Monte Carlo Simulation Techniques' is developed based on the data of a multistage random sampling survey. The total compensation rate, the decreased percentages of poverty caused by diseases and the deficit ratio of fund a 0.3782, 0.6540 and -0.0794 respectively, when the main strategy of inpatient reimbursement is recognized as 'serious illness'. The deficit ratios of funding appeared to be 0.4840, 0.4091 and -0.3789 when the main strategy of outpatient reimbursement is recognized on minor diseases. Compensation for minor diseases is more important than that of serious diseases. Considering the further impact of minor diseases on peasants, we should incorporate compensation for minor diseases into the compensatory scheme of NCMS.

Number needed to be screened in a study: a novel measure for disease screening effect / 中华流行病学杂志

<p><b>OBJECTIVE</b>To introduce the concept, methods for calculation and application of "number needed to be screened" (NNBS) in epidemiologic studies.</p><p><b>METHODS</b>The concept of "number needed to treat" (NNT) was extended for disease screening strategies. For the purpose of illustration, the values of number needed to invite for screening (NNI) and number needed to be screened (NNBS) were calculated on the basis of the results from two randomized controlled screening trials--Nottingham randomized controlled trial of faecal-occult-blood screening for colorectal cancer and Swedish mammographic screening trial for breast cancer in two counties.</p><p><b>RESULTS</b>In order to prevent one death from the colorectal cancer among local people aged from 45 to 74 during the 14 years of follow-up, the NNI and NNBS for faecal-occult-blood screening program were 1220 and 665, respectively. In addition, in order to prevent one death from breast cancer among local women aged 40-74 during 8 years of follow-up, the NNI and NNBS for mammographic screening program were 1961 and 1494, respectively.</p><p><b>CONCLUSION</b>Compared with the traditional indices, NNBS can evaluate the overall effectiveness of a screening program in an intuitively understandable manner so as to facilitate the communication among medical researchers, health workers, health policy makers and the public.</p>

A case-control study on the association between the genetic polymorphism of sulfotransferase 1A1, diet and susceptibility of colorectal cancer / 中华肿瘤杂志

<p><b>OBJECTIVE</b>To investigate the relationship between sulfotransferase 1Al polymorphism, diet and colorectal cancer susceptibility.</p><p><b>METHODS</b>A case-control study of 140 cancers and 343 health controls was conducted to investigate the role of sulfotransferase 1A1 polymorphism and meat consumption in colorectal carcinogenesis. Genotypes of sulfotransferase 1A1 polymorphism were analyzed by polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP).</p><p><b>RESULTS</b>There was no significant difference in allele frequency of SULT1A1 between the control and cancer patient populations. After adjustment for age, sex, smoking and history of diseases, red meat and well-done meat intake showed no significant association with colorectal cancer. Consumption of red meat more than 5 kg per year combined with SULT1Al slow sulfation (Arg/His and His/His) had a statistically significant association with the risk of rectal cancer ( OR = 3.78; 95% CI: 1.08 - 13. 20) compared to that consumed red meat less than 5 kg per year with fast sulfation (Arg/Arg).</p><p><b>CONCLUSION</b>This study suggests that SULT1A1 slow sulfation combined with higher intake of red meat may be associated with an elevated risk of rectal cancer.</p>

A method for measuring the contribution of individual factor to disease caused by multiple risk factors / 中华流行病学杂志

<p><b>OBJECTIVE</b>To evaluate the contribution of individual risk factor to a disease on someone with several risk factors.</p><p><b>METHODS</b>A method based on epidemiological theory and Bayes' theorem was established to measure the contribution of individual risk factor, using the relative risk (RR) or odds ratio (OR) value obtained from population-based cohort studies or meta-analysis.</p><p><b>RESULTS</b>The proportional contribution for individual risk factor to disease in one person can be measured or estimated.</p><p><b>CONCLUSION</b>This method can be applied to risk assessment in a patient with more than one risk factor, and the results also contribute to our etiological study and clinical decision-making strategy.</p>

Concept on the use of "number needed to be exposed" in epidemiology / 中华流行病学杂志

<p><b>OBJECTIVE</b>To introduce the concept, methods for calculation and application of "number needs to be exposed (NNE)" in Epidemiological studies.</p><p><b>METHODS</b>Data was analyzed from a study on the association between diaspirin cross-linked hemoglobin (DCLHb) with 28-day mortality in patients with severe traumatic hemorrhagic shock.</p><p><b>RESULTS</b>The crude "number needed to be exposed for one additional person to be harmed" (NNEH) was 3.7 (95% CI: 2.2-11.5) for the exposure to DCLHb. After controlling the confounding bias of the baseline mortality risk, the adjusted NNEH became 2.6 (95% CI: 1.6-8.0) id., on average, among 2.6 patients exposed to DCLHb, one additional case of death would have developed within 28 days after initial hospitalization if the distribution of baseline mortality risk in exposed group had been equal to that in the unexposed group.</p><p><b>CONCLUSION</b>NNE could be expressed as the estimated average number of persons needed to be exposed for contributing (either developing or preventing for) one additional case of disease or death in a prospective study when compared with the unexposed persons. As a new index for measuring the absolute effect of an exposure, NNE presented the results on epidemiological studies in a more intuitive and understandable manner. Consequently, this method could be favorably accepted by clinicians, health policy makers and the public.</p>

Glutathione S-transferase M1 polymorphism and the risk on colorectal cancer: a multilevel meta regression / 中华流行病学杂志

<p><b>OBJECTIVE</b>In order to investigate the relationship between Glutathione S-transferase M1 (GSTM1) status and the risk on colorectal cancer as well as to detect the related factors to this association.</p><p><b>METHODS</b>A pooled analysis of multilevel Meta-regression was performed to estimate GSTM1 deficiency associated with the risks of colorectal cancer. Then subgroup Meta-regression was undertaken to evaluate the possible relationship between heterogeneity and the related characteristics.</p><p><b>RESULTS</b>The overall pooled odds ratios of colorectal cancer risk associated with GSTM1 deficiency was 1.17 (95% CI: 1.08-1.26). Ethnicity, percent of GSTM1 deficiency in population had significant relationships with heterogeneity across the studies (P < 0.05). Results of subgroup Meta-regression showed that GSTM1 deficiency was significantly associated with colorectal cancer risk in ethnic subgroups of Asians, Caucasians and in low level (lower than 50%) of GSTM1 deficiency population (P < 0.05). The respective pooled ORs were 1.14, 1.25 and 1.29.</p><p><b>CONCLUSION</b>GSTM1 deficiency seemed to be a risk factor for colorectal cancer, while interactions on the characteristics of ethnicity, percentage of GSTM1 deficiency in the studied population were related to this association.</p>