Active Surveillance of Adverse Events Following Human Papillomavirus Vaccination: Feasibility Pilot Study Based on the Regional Health Care Information Platform in the City of Ningbo, China

Interpretable machine learning in predicting drug-induced liver injury among tuberculosis patients: model development and validation study

BACKGROUND

The objective of this research was to create and validate an interpretable prediction model for drug-induced liver injury (DILI) during tuberculosis (TB) treatment.

METHODS

A dataset of TB patients from Ningbo City was used to develop models employing the eXtreme Gradient Boosting (XGBoost), random forest (RF), and the least absolute shrinkage and selection operator (LASSO) logistic algorithms. The model's performance was evaluated through various metrics, including the area under the receiver operating characteristic curve (AUROC) and the area under the precision recall curve (AUPR) alongside the decision curve. The Shapley Additive exPlanations (SHAP) method was used to interpret the variable contributions of the superior model.

RESULTS

A total of 7,071 TB patients were identified from the regional healthcare dataset. The study cohort consisted of individuals with a median age of 47 years, 68.0% of whom were male, and 16.3% developed DILI. We utilized part of the high dimensional propensity score (HDPS) method to identify relevant variables and obtained a total of 424 variables. From these, 37 variables were selected for inclusion in a logistic model using LASSO. The dataset was then split into training and validation sets according to a 7:3 ratio. In the validation dataset, the XGBoost model displayed improved overall performance, with an AUROC of 0.89, an AUPR of 0.75, an F1 score of 0.57, and a Brier score of 0.07. Both SHAP analysis and XGBoost model highlighted the contribution of baseline liver-related ailments such as DILI, drug-induced hepatitis (DIH), and fatty liver disease (FLD). Age, alanine transaminase (ALT), and total bilirubin (Tbil) were also linked to DILI status.

CONCLUSION

XGBoost demonstrates improved predictive performance compared to RF and LASSO logistic in this study. Moreover, the introduction of the SHAP method enhances the clinical understanding and potential application of the model. For further research, external validation and more detailed feature integration are necessary.

[Research advances in the etiology and pathogenesis of immunoglobulin A vasculitis]

Immunoglobulin A vasculitis (IgAV), also known as Henoch-Schönlein purpura, has complex etiology and pathogenesis which have not been fully clarified. The latest research shows that SARS-CoV-2 and related vaccines, human papilloma vaccine, and certain biological agents can also induce IgAV. Most studies believe that the formation of galactose-deficient IgA1 (Gd-IgA1) and Gd-IgA1-containing immune complex plays a crucial role in the pathogenesis of IgAV. It is hypothesized that the pathogenesis of IgAV is associated with the binding of IgA1 to anti-endothelial cell antibodies. In addition, genetics also constitutes a major focus of IgAV research. This article reviews the new advances in the etiology of IgAV and summarizes the role of Gd-IgA1, Gd-IgA1-containing immune complex, anti-endothelial antibody, IgA1 conjugates, T lymphocyte immunity, and genetic factors in the pathogenesis of IgAV.

No increased risk of intussusception after pentavalent rotavirus vaccination in China: a retrospective birth cohort using electronic health records of Ningbo city

Some post-licensure studies have shown a potential increased risk of intussusception following vaccination with rotavirus vaccines. This is the first study that aimed to assess the incidence and risk of intussusception within 90 days after vaccination with RotaTeq in Chinese infants. A population-based birth cohort from 27th November 2018 to 30th June 2021 included all newborns in Ningbo city. The records of intussusception were identified through the ICD-10 code K56.1 or Chinese keywords "Chang Tao" from all hospital discharge records. Each episode was confirmed in line with the Brighton criteria, and only Brighton level 1 cases were included. The association of RotaTeq vaccination and intussusception was evaluated using the Poisson regression. A total of 108,405 eligible subjects from birth cohort were eligible, with 52.30% males. Among them, 26, 847 (24.77%) infants received at least one dose of RotaTeq, and 95.52% of them were fully vaccinated, with 76, 934 doses in total. After adjudication, none of the cases occurred post first, or second dose, the cumulative number of cases that occurred 1-7, 1-14, 1-21, 1-42, and 1-90 days post third dose was 0, 1, 1, 3, and 7, respectively. Adjusting for age, sex, birth year, birth season and location, the incidence rate ratio of intussusception after RotaTeq vaccination was 0.90 (90% two-sided CI: 0.46, 1.75). Increasing age and male gender were associated with higher risk of intussusception. In summary, no increased risk of IS was observed following 3 months of RotaTeq vaccination in this study.

A feasibility assessment of real-world data capabilities for monitoring vaccine safety and effectiveness in China: Human papillomavirus vaccination in the Yinzhou district as a use case

BACKGROUND

Real-world data (RWD) are increasingly used to generate real-world evidence (RWE) of vaccine safety and effectiveness for regulatory purposes. Assessing feasibility of using RWD sources prior to implementing observational studies is recommended. As a use case, we described the process and findings of a feasibility assessment to identify reliable and relevant data sources for monitoring the safety and effectiveness of the AS04-HPV-16/18 human papillomavirus (HPV) vaccine in China.

METHODS

Iterative multi-step process: (1) targeted literature review and data source mapping; (2) expert opinion from national RWD experts; (3) survey to evaluate the identified data source operational infrastructure; and (4) continuous appraisal of published studies using the identified data source.

RESULTS

The Yinzhou Regional Health Information Platform (YRHIP) was identified as a data source of main interest, based on its large population coverage, high cervical cancer screening rates, and availability of adult electronic immunization records. Field meetings with national RWD experts confirmed its suitability for post-authorization vaccine studies. Survey results showed that exposure data and relevant safety and effectiveness endpoints were recorded and linkable at the individual level across the platform. Iterative appraisal of emerging evidence from the literature corroborated these findings.

CONCLUSIONS

This feasibility assessment indicates that the YRHIP has the capacity to capture demographic, exposure, outcome and other data required to generate RWE on HPV vaccine safety and effectiveness in China. Studies using the YRHIP to monitor the AS04-HPV-16/18 vaccine in routine use building on this feasibility assessment are ongoing.

MOnitoring human papillomavirus Vaccine effect on Infection and cErvical diseases (MOVIE): Protocol for a cohort study using electronic health records from Yinzhou, China

Cervical cancer is the fourth most common cancer in women, with a high disease burden worldwide. Human papillomavirus (HPV) vaccination reduces HPV-related infection and associated cervical lesions and cancers. Few studies have explored HPV vaccination impact in real-world settings in China. This study aims to monitor HPV vaccine uptake and its effects on HPV-related diseases, evaluating vaccine effectiveness in a real-world context and complementing clinical trial results. Electronic health records (EHRs) from 2010 to 2020 from the Yinzhou Regional Health Information Platform (YRHIP) will be queried/extracted to identify and monitor HPV vaccine uptake in females aged 9-45 years, and HPV-related screening and prevalence (i.e., cervical HPV infection, cervical intraepithelial neoplasia [CIN] grades 1-3, and cervical cancer) in a cohort of females aged 9-70 years. Cervical cancer screening guidelines and expert consultation will be used for intra-database validation, to determine the best algorithm for identifying HPV-related disease. Pre-launch (2010-2016) and post-launch (2018-2020) periods are predefined. A time trend analysis will be performed to describe the vaccination impact on disease prevalence and, if prerequisite conditions are met, vaccine effectiveness will be computed using logistic regression, adjusting for age, calendar year, history of screening and HPV infection. Cohort study design, outcomes validation, data linkage, and multi-step statistical analyses could provide valuable experience for designing other real-world studies in the future. The study outcomes can help inform policy-makers about uptake and HPV vaccination policy in girls and women in Yinzhou District, and provide insights on progress toward achieving goals set by the World Health Organization.

Awareness of HPV and HPV vaccines, acceptance to vaccination and its influence factors among parents of adolescents 9 to 18 years of age in China: A cross-sectional study

BACKGROUND

Vaccination uptake rates for adolescents are still low in China despite safe and effective human papillomavirus vaccines being available. The awareness and attitudes of parents to HPV vaccines play a decisive role in adolescents' HPV vaccination uptake.

METHODS

A cross-sectional study was conducted from March, 2022 to May, 2022 using an anonymous questionnaire among parents of 9 to 18 years of age from 73 cities in 23 provinces in mainland China. Demographic characteristics of parents, their knowledge and attitudes about HPV and HPV vaccination, as well as factors influencing HPV vaccination in adolescents were assessed.

RESULTS

More than two-thirds of parents heard of HPV (75.5%) and HPV vaccines (84.7%). Of these participants, mothers (83.8%) were in the majority. Parents willing to vaccinate themselves and their children against HPV were 84.9% and 87.6%, respectively. Parents were more likely to vaccinate their daughters against HPV than their sons (P < 0.001). Parents who had heard of the HPV vaccines (P = 0.028) or had vaccinated themselves (P < 0.001) were more likely to have HPV vaccination for their children. Parents who accepted the price of the HPV vaccines (P = 0.005) were more likely to have their children vaccinated against HPV.

CONCLUSIONS

Children's gender, awareness of the HPV vaccines, parental HPV vaccination, and the price of the HPV vaccines are likely to be the reason for parents' vaccine hesitancy for adolescents.

PRACTICE IMPLICATIONS

Nurses have a critical role in identifying parental hesitancy and providing individualized education to expand the parental awareness and knowledge and encourage on-time adolescents vaccination.

Risk of peripheral facial palsy following parenteral inactivated influenza vaccination in the elderly Chinese population

Background

Concern about the risk of peripheral facial palsy (PFP) following vaccination is one reason for hesitancy in influenza vaccination. However, the association between the flu vaccine and PFP is still controversial, and further evidence is urgently needed.

Methods

This self-controlled case series study evaluated PFP risk following inactivated influenza vaccine in the elderly using a large linked database in Ningbo, China. Relative incidence ratios (RIRs) and 95% confidence intervals (CIs) estimated using conditional Poisson regression were utilized to determine whether the risk of PFP was increased after vaccination.

Results

This study included 467 episodes, which occurred in 244 females and 220 males. One hundred twenty-four episodes happened within 1-91 days after vaccination, accounting for 26.7%. The adjusted RIRs within 1-30 days, 31-60 days, 61-91 days, and 1-91 days after influenza vaccination were 0.95 (95% CI 0.69-1.30), 1.08 (95% CI 0.78-1.49), 1.01 (95% CI 0.70-1.45), and 1.00 (95% CI 0.81-1.24), respectively. Similar results were found in subgroup analyses and sensitivity analyses.

Conclusions

Influenza vaccination does not increase PFP risk in the elderly population. This finding provides evidence to overcome concerns about facial paralysis after influenza vaccination.

Diagnostic validation and development of an algorithm for identification of intussusception in children using electronic health records of Ningbo city in China

BACKGROUND

Monitoring the risk of intussusception after the introduction of rotavirus vaccines is recommended by the World Health Organization (WHO). Although the validity of intussusception monitoring using electronic health records (EHRs) has been confirmed previously, no similar studies have been conducted in China. We aimed to verify the diagnosis and determine an algorithm with the best performance for identification of intussusception using Chinese EHR databases.

RESEARCH DESIGN AND METHODS

Using the Regional Health Information Platform in Ningbo, patients aged 0-72 months from 2015 to 2021 with any related visits for intussusception were included. The algorithms were based on diagnostic codes or keywords in different clinical scenarios, and their performance was evaluated with positive predictive value (PPV) and sensitivity in line with the Brighton guidelines.

RESULTS

Brighton level 1 intussusception was confirmed in 2958 patients with 3246 episodes. Fine-tuned algorithms combining the appearance of the relevant ICD-10 codes or the Chinese keyword 'Chang Tao' in any diagnostic reports with the results of enema treatments or related surgeries showed the highest sensitivity, while the highest PPV was obtained by further criteria based on typical radiographic appearances.

CONCLUSION

Intussusception could be identified and validated internally using EHRs in Ningbo.

Post-marketing surveillance for the safety of the 9-valent human papillomavirus vaccine: a retrospective real-world study in China

BACKGROUND

The 9-valent human papillomavirus (9vHPV) vaccine was introduced in China in 2018. This study was conducted to monitor the occurrence of new-onset autoimmune diseases (AIs) in Chinese women vaccinated with the 9vHPV vaccine and adverse pregnancy outcomes in infants born to mothers with inadvertent pregnancy exposure.

RESEARCH DESIGN AND METHODS

Women who received the first dose of the 9vHPV vaccine at age 16-26 years in Ningbo between January 2019 and March 2021 were monitored in the Ningbo Regional Health Information Platform. New-onset cases of seven pre-specified AIs diagnosed within six months after vaccination were collected. Cases of stillbirth and 23 major congenital anomalies diagnosed within three months of birth in target infants were collected.

RESULTS

A total of 102,670 doses of the 9vHPV vaccine were administered to 41,609 women who had received no other HPV vaccine. New-onset AIs were diagnosed in 36 women, comprising 21 Hashimoto's, 11 Graves', and 4 uveitis disease cases. Among 50 women with maternal vaccination exposure, no stillbirths were observed. One case of microtia was observed.

CONCLUSIONS

In this first post-marketing surveillance of the 9vHPV vaccine in China, no safety signals were identified when putting the results in context to published data.

Bilateral Optic Neuritis after COVID-19 Vaccination: A Case Report

BACKGROUND

Neuro-ophthalmic manifestations after vaccines are rare, with optic neuritis (ON) being the most common presentation. Patients with vaccine-related ON are similar to those with idiopathic ON. The temporal relationship between vaccination against and the occurrence of ON is vital. Here, we report a case of bilateral ON after the administration of the ChAdOx1-S nCoV-19 SARS-CoV-2 vaccine.

CASE

A 49-year-old healthy Asian female presented with sudden onset of bilateral blurred vision within 2 days. She complained of photophobia and extraocular pain upon movement over 3 days. Upon examination, her best corrected visual acuity (BCVA) was 20/30 in the right eye and 20/200 in the left eye. Anterior segment findings were unremarkable, with normal intraocular pressure. Fundoscopic examination revealed bilateral disc edema with vessel engorgement. Visual field examination revealed profound visual field defect in both eyes. She denied any trauma, use of new medication or medical history. She had received the ChAdOx1 nCoV-19 SARS-CoV-2 vaccine 14 days prior. Under suspicion of vaccine-related optic neuritis, she was given intravenous methylprednisolone 1 gm/day for 3 days, shifting to oral prednisolone under gradual tapering for 2 weeks.

CONCLUSIONS

Typically presenting with sudden-onset visual decline and extraocular pain during movement, acute ON is generally idiopathic. Bilateral ON is rare, but quick identification is important because it can potentially lead to permanent loss of vision if left untreated. Vaccination-induced ON is even rarer but not difficult to treat. However, such patients require further evaluation and long-term follow-up because they may be prone to other neurological disorders in the future.

Lack of association between febrile seizures and vaccines containing diphtheria, tetanus, and acellular pertussis in Chinese children

BACKGROUND

The association between the administration of vaccines containing diphtheria, tetanus, and acellular pertussis (DTaP) and febrile seizures (FSs) is unclear. This study aimed to evaluate the risk of FSs after the administration of DTaP-containing vaccines in Chinese children aged 1 to 23 months.

RESEARCH DESIGN AND METHODS

A self-controlled case series (SCCS) design was adopted based on data from the Ningbo Regional Health Information Platform (NRHIP). The observation period was from 1 to 23 months of age. The relative incidences (RIs) within 0 to 3 days, 4 to 7 days, and 0 to 7 days after the administration of DTaP-containing vaccines were estimated. The remaining observation period was the control period.

RESULTS

The RIs within 0 to 3 days, 4 to 7 days, and 0 to 7 days after any dose of DTaP-containing vaccines were 1.14 (95% CI 0.86 to 1.52), 0.89 (95% CI 0.65 to 1.23), and 1.02 (95% CI 0.82 to 1.26), respectively.

CONCLUSIONS

This study provides reassuring evidence that there is no increased risk of FSs immediately after the administration of DTaP-containing vaccines, which might serve to reassure both professionals and families with regard to the risk of FSs associated with DTaP-containing vaccines.

No association between enterovirus 71 (EV71) vaccination and risk of febrile seizures: a population-based near real-time surveillance study

BACKGROUND

Since 2016, vaccines against enterovirus 71 (EV71) infection have been approved for use in China. Reports to the national passive surveillance system raised concerns about febrile seizures (FS) after EV71 vaccination. Rapid safety assessment of this novel vaccine is a public health priority. The objective was to assess risks of FS following EV71 vaccination in China.

METHODS

We used data from a Regional Health Information Platform in Ningbo. The exposed population was children aged 6-71 months who received any dose of EV71 vaccine from 1 January 2016 to 31 December 2019. We implemented a multilayered approach to actively monitor FS following EV71 vaccination that included near real-time surveillance using two complementary sequential designs and further signal evaluation performing self-controlled risk interval (SCRI) analyses.

RESULTS

A total of 330,668 EV71 doses were administered to the study population. During 157 weeks of sequential analyses, no statistically increased risks were detected, when compared with the self-matched control interval or the background risk. Further SCRI analyses confirmed no associations between EV71 vaccination and FS (adjusted incidence rate ratio: 1.04, 95% CI: 0.75 to 1.43).

CONCLUSIONS

Our results reassured the safety of FS after EV71 vaccination using postlicensure data for the first time.

Factors Influencing the Popularity of a Health-Related Answer on a Chinese Question-and-Answer Website: Case Study

BACKGROUND

Social question-and-answer (Q&A) sites have become an important venue for individuals to obtain and share human papillomavirus (HPV) vaccine knowledge.

OBJECTIVE

This study aims to examine how different features of an HPV vaccine-related answer are associated with users' response behaviors on social Q&A websites.

METHODS

A total of 2953 answers and 270 corresponding questions regarding the HPV vaccine were collected from a leading Chinese social Q&A platform, Zhihu. Three types of key features, including content, context, and contributor, were extracted and coded. Negative binomial regression models were used to examine their impact on the vote and comment count of an HPV vaccine-related answer.

RESULTS

The findings showed that both content length and vividness were positively related to the response behaviors of HPV vaccine-related answers. In addition, compared with answers under the question theme benefits and risks, answers under the question theme vaccination experience received fewer votes and answers under the theme news opinions received more votes but fewer comments. The effects of characteristics of contributors were also supported, suggesting that answers from a male contributor with more followers and no professional identity would attract more votes and comments from community members. The significant interaction effect between content and context features further showed that long and vivid answers about HPV vaccination experience were more likely to receive votes and comments of users than those about benefits and risks.

CONCLUSIONS

The study provides a complete picture of the underlying mechanism behind response behaviors of users toward HPV vaccine-related answers on social Q&A websites. The results help health community organizers develop better strategies for building and maintaining a vibrant web-based community for communicating HPV vaccine knowledge.

Febrile Seizures and Measles-Containing Vaccines in China: A Self-Controlled Case Series Study

Little is known about the risk of febrile seizures (FS) after vaccination with measles-containing vaccines (MCVs) in middle- and low-income countries. This self-controlled case series study aimed to evaluate the risk of FSs in Chinese children using data from the Ningbo Regional Health Information Platform. The observation period was 0-12 and 13-24 months of age for the MR and MMR vaccines, respectively. The relative incidences (RIs) within 0-6 days, 7-13 days, 14-27 days, and 28-42 days after vaccination with MCVs were estimated. The remaining observation period was the control period. The RIs within 0-6 days, 7-13 days, 14-27 days, and 28-42 days after MR vaccination were 1.11 [95% confidence interval (CI) 0.33 to 3.70], 0.80 (95% CI 0.23 to 2.86), 1.67 (95% CI 0.81 to 3.42), and 1.02 (95% CI 0.49 to 2.14), respectively. The corresponding RIs after MMR vaccination were 0.99 (95% CI 0.56 to 1.75), 1.17 (95% CI 0.68 to 2.01), 0.87 (95% CI 0.54 to 1.39), and 0.85 (95% CI 0.54 to 1.34), respectively. This study suggests that China's vaccination schedule for MCVs, as suggested by the World Health Organization (WHO) for countries with a high risk of measles mortality and ongoing transmission, does not increase the risk of FSs.

[Epidemiological and etiological characteristics of hand, foot and mouth disease among children aged 5 years and younger in Ningbo (2016 to 2019)]

OBJECTIVE

To describe the epidemiological and etiological characteristics of hand, foot and mouth disease (HFMD) among children aged 5 years and younger in Ningbo after the access of entero-virus-A71 vaccine (2016 to 2019).

METHODS

A retrospective cohort study were performed in children aged 5 years and younger in Ningbo from 2016 to 2019. Data for incidence of HFMD was collected from the National Notifiable Disease Surveillance Reporting System and the Electronic Medical Records (EMRs) System, while the demographic information was derived from the Immunization Information System. Speci-mens were detected by real-time fluorescence quantitative PCR and the Wilson method was used to estimate the incidence rate and 95% confidence interval.

RESULTS

From 2016 to 2019, a total of 1 044 800 residential children were observed in this population-based cohort. In the study, 102 471 cases of HFMD were diagnosed in 2 651 081 person-years, revealing an overall incidence density of 3 865.25/100 000 person-years. There was no significant decline in the number of the cases after the vaccine was available. The number of the patients of hand foot mouth disease during the four years was 93 421, of whom 84 875 (90.85%) had only one incident record, while 8 946 (9.15%) had 2 or more cases in this period; there were 69 771 (66.06%) patients who only needed to see a doctor once for each disease, 19.92% of the patients needed to be treated twice, and 14 801 (14.02%) patients needed to go to the hospital or clinic three times or more. The incidence of HFMD showed obvious seasonality and periodicity, which mainly concentrated in April to July each year, and the epidemic cycle was 2 years; most of the cases were 1 to 3-year old children, with more cases in male. The incidence density varied across the region, with the highest density observed in Ninghai (4 524.76/100 000 person-years), followed by Xiangshan (3 984.22/100 000 person-years). In 3 748 library-conformed cases, 2 834(75.61%) were detected positive, among which enterovirus-A71, Cox-A16 and other enteroviruses accounted for 9.03%, 31.55% and 59.42%, respectively. During the study period, the cumulative coverage of enterovirus-A71 vaccine increased year by year, with the proportion of enterovirus-A71 and severe cases both gradually decreasing.

CONCLUSION

The current status of hand, foot and mouth disease in Ningbo is still serious. Children under 3-year old (especially male children aged 1 year) were the key population for prevention and control. Vaccination might lead to changes in major pathogenic virus type, of which more attention should be paid to the potential impact on disease surveillance, prevention and control.

[Epidemiological study of infantile epilepsy incidence density among infants under 36 months of age in Ningbo City from 2015 to 2019]

OBJECTIVE

To describe the distribution and trend of infantile epilepsy among infants under 36 months in Ningbo, Zhejiang Province.

METHODS

Using the birth cohort design, we retrospectively collected the local born infants in Ningbo national health information platform from 2015 to 2019, and took the first visit of epilepsy in the electronic medical record of the platform as the new case. The incidence density and 95% confidence interval (CI) of epilepsy were estimated by Poisson distribution.

RESULTS

From 2015 to 2019, a total of 294 900 children were born in Ningbo, with male accounting for 51.92%. The total person-years of observation were 595 300, while the median follow-up person-years was 2.31 [interquartile range (IQR): 1.90]. There were 575 new onset epilepsy patients during the whole observation period. The total number of visits was 2 599, with an average of 4.52. The total incidence density was 96.59/100 000 person-years (95%CI: 88.85-104.82). The median age of onset was 13 months (IQR: 15), 0-12 months old infants had the highest incidence density (102.18/100 000 person-years), 25-36 months old infants had the lowest incidence density (89.68/100 000 person-years), and the difference was not statistically significant (P>0.05). The incidence density of male was 97.58/100 000 person-years, female was 95.53/100 000 person-years, and the difference was not statistically significant (P>0.05). Fenghua was the highest (130.54/100 000 person-years, 95%CI: 94.47-175.83) and Ninghai was the lowest (66.44/100 000 person-years, 95%CI: 47.02-91. 19), with significant difference (P < 0.05). There was no significant difference in the incidence density in different birth years (P>0.05). There was significant difference in the incidence density between 0-12 months old infants in different calendar years (P_trend < 0.05). In this age group, the incidence density was the lowest in 2015 (69.41/100 000 person-years, 95%CI: 41.79-108.39), and the highest in 2019 (225.61/100 000 person-years, 95%CI: 186.10-271.03). There was no significant difference in the incidence density between 13-24 and 25-36 months old infants in different calendar years (P>0.05).

CONCLUSION

The incidence density of epilepsy in 0-36 months old infants in Ningbo City from 2015 to 2019 was low as a whole, and there was no difference in age group, gender, and year of birth. The incidence density of 0-12 months old infants increased with the year.

[Epidemiological and etiological characteristics of hand, foot and mouth disease among children aged 5 years and younger in Ningbo (2016 to 2019)]

OBJECTIVE

To describe the epidemiological and etiological characteristics of hand, foot and mouth disease (HFMD) among children aged 5 years and younger in Ningbo after the access of entero-virus-A71 vaccine (2016 to 2019).

METHODS

A retrospective cohort study were performed in children aged 5 years and younger in Ningbo from 2016 to 2019. Data for incidence of HFMD was collected from the National Notifiable Disease Surveillance Reporting System and the Electronic Medical Records (EMRs) System, while the demographic information was derived from the Immunization Information System. Speci-mens were detected by real-time fluorescence quantitative PCR and the Wilson method was used to estimate the incidence rate and 95% confidence interval.

RESULTS

From 2016 to 2019, a total of 1 044 800 residential children were observed in this population-based cohort. In the study, 102 471 cases of HFMD were diagnosed in 2 651 081 person-years, revealing an overall incidence density of 3 865.25/100 000 person-years. There was no significant decline in the number of the cases after the vaccine was available. The number of the patients of hand foot mouth disease during the four years was 93 421, of whom 84 875 (90.85%) had only one incident record, while 8 946 (9.15%) had 2 or more cases in this period; there were 69 771 (66.06%) patients who only needed to see a doctor once for each disease, 19.92% of the patients needed to be treated twice, and 14 801 (14.02%) patients needed to go to the hospital or clinic three times or more. The incidence of HFMD showed obvious seasonality and periodicity, which mainly concentrated in April to July each year, and the epidemic cycle was 2 years; most of the cases were 1 to 3-year old children, with more cases in male. The incidence density varied across the region, with the highest density observed in Ninghai (4 524.76/100 000 person-years), followed by Xiangshan (3 984.22/100 000 person-years). In 3 748 library-conformed cases, 2 834(75.61%) were detected positive, among which enterovirus-A71, Cox-A16 and other enteroviruses accounted for 9.03%, 31.55% and 59.42%, respectively. During the study period, the cumulative coverage of enterovirus-A71 vaccine increased year by year, with the proportion of enterovirus-A71 and severe cases both gradually decreasing.

CONCLUSION

The current status of hand, foot and mouth disease in Ningbo is still serious. Children under 3-year old (especially male children aged 1 year) were the key population for prevention and control. Vaccination might lead to changes in major pathogenic virus type, of which more attention should be paid to the potential impact on disease surveillance, prevention and control.

Active Vaccine Safety Surveillance: Global Trends and Challenges in China

Importance. The great success in vaccine-preventable diseases has been accompanied by vaccine safety concerns. This has caused vaccine hesitancy to be the top 10 in threats to global health. The comprehensive understanding of adverse events following immunization should be entirely based on clinical trials and postapproval surveillance. It has increasingly been recognized worldwide that the active surveillance of vaccine safety should be an essential part of immunization programs due to its complementary advantages to passive surveillance and clinical trials.Highlights. In the present study, the framework of vaccine safety surveillance was summarized to illustrate the importance of active surveillance and address vaccine hesitancy or safety concerns. Then, the global progress of active surveillance systems was reviewed, mainly focusing on population-based or hospital-based active surveillance. With these successful paradigms, the practical and reliable ways to create robust and similar systems in China were discussed and presented from the perspective of available databases, methodology challenges, policy supports, and ethical considerations.Conclusion. In the inevitable trend of the global vaccine safety ecosystem, the establishment of an active surveillance system for vaccine safety in China is urgent and feasible. This process can be accelerated with the consensus and cooperation of regulatory departments, research institutions, and data owners.

A nationwide post-marketing survey of knowledge, attitudes and recommendations towards human papillomavirus vaccines among healthcare providers in China

Since licensure of human papillomavirus (HPV) vaccine in mainland China, little research has been conducted about healthcare providers' (HCPs) understanding and recommendation of HPV vaccine. A multi-stage convenience sample of Chinese HCPs (N = 5270) were surveyed, involving obstetrician-gynecologists, HCPs from Division of Expanded Program on Immunization (DEPI), Community Health Center (CHC) and other non-HPV closely related professions. Binary logistic regression was conducted to explore factors associated with knowledge and recommendation behaviors. Overall, HCPs showed basic HPV/HPV vaccine knowledge with median (interquartile range) score at 9.5 (7.5-11.6) out of 16 and relatively high recommendation behavior (74.8%). Identified knowledge gaps among HCPs included risk factors of HPV infection, best time to vaccinate, prophylactic functions of HPV vaccine and especially classification of low-risk and high-risk types. Profession-specific analysis in individual knowledge item showed HCPs from CHC were suboptimal on HPV while obstetrician-gynecologists were less competent on HPV vaccine knowledge. Obstetrician-gynecologists also recommended vaccination less frequently than HCPs from DEPI and CHC. Besides being key predictors of recommendation practice (2.74, 95% CI: 2.34-3.21), knowledge shared independent determinants with recommendation behavior on age and ethnicity and additionally associated with education and title by itself. Findings highlight overall and profession-specific gaps on HPV and HPV vaccine knowledge and recommendation practice. Future education and training efforts should be profession-niche-targeting and focus much on HCPs with lower title or education background and from minorities.