Research

15 pages, 307 KiB

Open AccessArticle

COVID-19 Vaccination Coverage among 42,565 Adults Amid the Spread of Omicron Variant in Beijing, China

by Chenyuan Qin, Min Du, Yaping Wang, Mingyue Li, Hao Wu, Shugang Li and Jue Liu

Vaccines 2023, 11(4), 739; https://doi.org/10.3390/vaccines11040739 - 27 Mar 2023

Cited by 1 | Viewed by 1098

Vaccines against coronavirus disease 2019 (COVID-19) have been in use for over two years, but studies that reflect real-world vaccination coverage and demographic determinants are lacking. Using a multistage stratified random cluster sampling method, we planned to directly explore vaccination coverage and the [...] Read more.

Vaccines against coronavirus disease 2019 (COVID-19) have been in use for over two years, but studies that reflect real-world vaccination coverage and demographic determinants are lacking. Using a multistage stratified random cluster sampling method, we planned to directly explore vaccination coverage and the demographic determinants of different doses of COVID-19 vaccines in Beijing, especially in older populations. All 348 community health service centers in 16 districts were involved. We performed multivariable logistic regression analyses to identify demographic determinants of different coverage rates via adjusted odds ratios (aORs) and 95% CIs. Of the 42,565 eligible participants, the total vaccination coverage rates for ≥1 dose, ≥2 doses, ≥3 doses, and 4 doses were 93.3%, 91.6%, 84.9%, and 13.0%, respectively, but decreased to 88.1%, 85.1%, 76.2%, and 3.8% in the older population. Among all participants, younger (aOR = 1.77, 95% CI: 1.60–1.95), male (aOR = 1.15, 95% CI: 1.06–1.23), and better-educated residents (high school and technical secondary school aOR = 1.58, 95% CI: 1.43–1.74; bachelor’s degree aOR = 1.53, 95% CI: 1.37–1.70) were more likely to be fully vaccinated. People who lived in rural areas (aOR = 1.45, 95% CI: 1.31–1.60) and held the new rural cooperative health insurance (aOR = 1.37, 95% CI: 1.20–1.57) established a higher rate of full vaccination coverage. No history of chronic disease was positively associated with a higher coverage rate (aOR = 1.81, 95% CI: 1.66–1.97). Occupation also affected vaccination coverage. Demographic factors influencing the rate of vaccination with at least one or three doses were consistent with the results above. Results remained robust in a sensitivity analysis. Given the highly transmissible variants and declining antibody titers, accelerating the promotion of booster vaccination coverage, especially in high-risk groups such as the elderly, is a top priority. For all vaccine-preventable diseases, rapidly clarifying vaccine-hesitant populations, clearing barriers, and establishing a better immune barrier can effectively safeguard people’s lives and property and coordinate economic development with epidemic prevention and control. Full article

(This article belongs to the Special Issue Current Use and Development of Vaccines in China)

15 pages, 297 KiB

Open AccessArticle

Policy Endorsement and Booster Shot: Exploring Politicized Determinants for Acceptance of a Third Dose of COVID-19 Vaccine in China

by Ruifen Zhang, Jun Yan, Hepeng Jia, Xi Luo, Qinliang Liu and Jingke Lin

Vaccines 2023, 11(2), 421; https://doi.org/10.3390/vaccines11020421 - 12 Feb 2023

Cited by 5 | Viewed by 1393

Abstract

China’s recent termination of strict COVID-19 control necessitates taking a booster vaccine shot as a precaution against the pandemic as quickly as possible. A large body of research has examined people’s attitudes toward and intentions for the booster shot. However, most studies failed [...] Read more.

China’s recent termination of strict COVID-19 control necessitates taking a booster vaccine shot as a precaution against the pandemic as quickly as possible. A large body of research has examined people’s attitudes toward and intentions for the booster shot. However, most studies failed to explore how China’s sociopolitical context has shaped their attitude regarding the booster jab take-up. The current study utilizes data from a national survey adopting quota sampling to analyze the Chinese public’s medical and non-medical considerations to determine their intention for the third dose of the COVID-19 vaccine. The study found that thanks to China’s initial successful lockdown policies, personal risk and benefit perceptions did not dominate their views regarding booster vaccination. Instead, respondents’ gender, nationalism, endorsement of the zero-COVID policy, self-efficacy regarding vaccination, and perceived infection severity were the major factors underlying their booster shot intention. The situation highlights how the politicized context of China’s COVID-19 control has impacted people’s plans to practice preventive behaviors. It is necessary to offset the negative consequences. One strategy is to educate the Chinese public with more medically relevant information to help them make rational choices regarding vaccination and other protective measures. On the other hand, such education can utilize this nationalistic mental status to enhance the persuasion effect. Full article

(This article belongs to the Special Issue Current Use and Development of Vaccines in China)

14 pages, 989 KiB

Open AccessArticle

Information-Seeking Behavior for COVID-19 Boosters in China: A Cross-Sectional Survey

by Xiaoshan Austin Li, Qiwei Luna Wu, Katharine Hubbard, Jooyun Hwang and Lingzi Zhong

Vaccines 2023, 11(2), 323; https://doi.org/10.3390/vaccines11020323 - 31 Jan 2023

Cited by 1 | Viewed by 1341

Abstract

As China launches its second COVID-19 booster campaign and races to bring new vaccine technologies to protect against severe COVID-19 infections, there is limited research on how Chinese residents search for vaccine-related information. This study examined the factors influencing Chinese residents’ information-seeking behaviors [...] Read more.

As China launches its second COVID-19 booster campaign and races to bring new vaccine technologies to protect against severe COVID-19 infections, there is limited research on how Chinese residents search for vaccine-related information. This study examined the factors influencing Chinese residents’ information-seeking behaviors regarding COVID-19 boosters with a sample of 616 respondents with a mean age of 31.53 from a research panel. Structural equation modeling was used to report factors that influenced respondents’ seeking intent. The results indicated that seeking-related subjective norms (β = −0.55, p < 0.001), negative affect (β = 0.08, p < 0.05), positive affect (β = 0.18, p < 0.001), and perceived knowledge insufficiency (β = 0.10, p < 0.001) are strong predictors of one’s seeking intent. We also discovered that there was an inverse relationship between risk perception and positive affect (β = −0.55, p < 0.001) and between negative and positive affect (β = −0.19, p < 0.01), while all measurements were either directly or indirectly related to information-seeking intent. A few more indirect but important relationships were also included in our discussion. In conclusion, the present study helps understand what motivates Chinese residents to seek COVID-19 booster information when limited information is available. Full article

(This article belongs to the Special Issue Current Use and Development of Vaccines in China)

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13 pages, 1134 KiB

Open AccessArticle

Healthcare Workers’ Attitudes toward Influenza Vaccination: A Behaviour and Social Drivers Survey

by Binshan Jiang, Yanlin Cao, Jie Qian, Mingyue Jiang, Qiangru Huang, Yanxia Sun, Peixi Dai, Heya Yi, Run Zhang, Lili Xu, Jiandong Zheng, Weizhong Yang and Luzhao Feng

Vaccines 2023, 11(1), 143; https://doi.org/10.3390/vaccines11010143 - 09 Jan 2023

Cited by 3 | Viewed by 1566

Abstract

This study aimed to understand the intention and correlation of receiving and recommending influenza vaccine (IV) among healthcare workers (HCWs) in China during the 2022/2023 season using the behavior and social drivers (BeSD) tools. A self-administered electronic survey collected 17,832 participants on a [...] Read more.

This study aimed to understand the intention and correlation of receiving and recommending influenza vaccine (IV) among healthcare workers (HCWs) in China during the 2022/2023 season using the behavior and social drivers (BeSD) tools. A self-administered electronic survey collected 17,832 participants on a media platform. We investigated the willingness of IV and used multivariate logistic regression analysis to explore its associated factors. The average scores of the 3Cs’ model were compared by multiple comparisons. We also explored the factors that potentially correlated with recommendation willingness by partial regression. The willingness of IV was 74.89% among HCWs, and 82.58% of the participants were likely to recommend it to others during this season. Thinking and feeling was the strongest domain independently associated with willingness. All domains in BeSD were significantly different between the hesitancy and acceptance groups. Central factors in the 3Cs model were significantly different among groups (p < 0.01). HCWs’ willingness to IV recommendation was influenced by their ability to answer related questions (r = 0.187, p < 0.001) after controlling for their IV willingness and perceived risk. HCWs’ attitudes towards IV affect their vaccination and recommendation. The BeSD framework revealed the drivers during the decision-making process. Further study should classify the causes in detail to refine HCWs’ education. Full article

(This article belongs to the Special Issue Current Use and Development of Vaccines in China)

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15 pages, 1009 KiB

Open AccessArticle

Caregiver Willingness to Vaccinate Children with Pneumococcal Vaccines and to Pay in a Low-Resource Setting in China: A Cross-Sectional Study

by Linqiao Li, Yuan Ma, Wei Li, Guorong Tang, Yan Jiang, Huangcui Li, Shuxiang Jiang, Yun Zhou, Yuan Yang, Ting Zhang, Weizhong Yang, Libing Ma and Luzhao Feng

Vaccines 2022, 10(11), 1897; https://doi.org/10.3390/vaccines10111897 - 10 Nov 2022

Cited by 4 | Viewed by 1404

Abstract

To determine the vaccine hesitancy of pneumococcal conjugate vaccines (PCVs) in a low-resource setting in China and to identify associated factors, a face-to-face questionnaire survey was conducted in the city of Guilin, China, from December 2021 to March 2022, which comprised sociodemographic information, [...] Read more.

To determine the vaccine hesitancy of pneumococcal conjugate vaccines (PCVs) in a low-resource setting in China and to identify associated factors, a face-to-face questionnaire survey was conducted in the city of Guilin, China, from December 2021 to March 2022, which comprised sociodemographic information, attitudes toward vaccines and pneumonia, and PCV13 vaccination willingness and willingness to pay (WTP). Stepwise logistic regression and Tobit regression models were fitted to identify factors associated with PCV13 vaccination willingness and WTP, respectively. In total, 1254 questionnaires were included, of which 899, 254, and 101 participants showed acceptance, hesitancy, and refusal to vaccinate their children with PCV13, respectively. Only 39.07% of participants knew about PCV13 before this survey. A total of 558 (48.40%) participants accepted the full payment of vaccination, and 477 (41.37%) other participants accepted the partial payment, with a median cost of CNY 920.00. Demographics, social and psychological context, and attitudes toward vaccines were all associated with PCV13 vaccination but varied for hesitators and refusers. There is a substantial local demand for vaccinating children with PCV13 and partial payment is widely accepted. More publicity and educational efforts and a socially supportive environment are required to alleviate vaccine hesitancy. Full article

(This article belongs to the Special Issue Current Use and Development of Vaccines in China)

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12 pages, 1180 KiB

Open AccessArticle

The Association between Risk Perception and Hesitancy toward the Booster Dose of COVID-19 Vaccine among People Aged 60 Years and Older in China

by Chenyuan Qin, Wenxin Yan, Liyuan Tao, Min Liu and Jue Liu

Vaccines 2022, 10(7), 1112; https://doi.org/10.3390/vaccines10071112 - 12 Jul 2022

Cited by 27 | Viewed by 3231

Abstract

Background: Given the prevalence of the omicron variant and decreased immunity provided by vaccines, it is imperative to enhance resistance to COVID-19 in the old population. We planned to explore the hesitancy rate toward the booster dose of the COVID-19 vaccine and the [...] Read more.

Background: Given the prevalence of the omicron variant and decreased immunity provided by vaccines, it is imperative to enhance resistance to COVID-19 in the old population. We planned to explore the hesitancy rate toward the booster dose of the COVID-19 vaccine and the association between risk perception and the abovementioned rate among people aged 60 and older. Methods: This national cross-sectional study was conducted in mainland China from 25 May to 8 June 2022, targeting people who were 60 years old or above. Four dimensions were extracted from the Health Belief Model (HBM) to assess participants’ perceived risk levels, including perceived susceptibility, perceived severity, perceived barriers, and perceived benefit. An independent Chi-square test was used to compare the vaccine hesitancy rates among different groups stratified by characteristics. Univariable and multivariable logistic regression models were performed to explore the associations between risk perception and hesitancy rate. Results: Of 3321 participants, 17.2% (95% CI: 15.9–18.5%) were hesitant about booster shots of COVID-19 vaccines. Believing that they were ineligible for vaccination due to certain illnesses (38.3%), concern about vaccine safety (32.0%), believing the booster shots were unnecessary (33.1%), and their limitation on movements (28.0%) were the main reasons for vaccine hesitation. Adjusted by all the selected covariates, people with low perception level of susceptibility (aOR = 1.39, 95% CI: 1.00–1.92) and benefit (low: aOR = 3.31, 95% CI: 2.01–5.45; moderate: aOR = 2.23, 95% CI: 1.75–2.85) were less likely to receiving the booster dose, and the same results were found in people with higher perceived barriers (moderate: aOR = 2.67, 95% CI: 2.13–3.35; high: aOR = 2.04, 95% CI: 1.14–3.67). Our estimates were stable in all four models. Conclusions: In total, 17.2% of the people aged 60 years and older in China were hesitant about booster dose of COVID-19 vaccines, and it was closely associated with a lower level of perceived susceptibility and benefit, as well as a higher level of perceived barriers. Concerns about contraindications, vaccine safety, and limited movements were the main reasons for vaccine hesitancy. Targeted public health measure is a priority to improve the understanding of the elderly on their own susceptibility and vulnerability and clear the obstacles to vaccination. Full article

(This article belongs to the Special Issue Current Use and Development of Vaccines in China)

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15 pages, 2338 KiB

Open AccessArticle

Evaluation of Immunogenicity and Safety of Vero Cell-Derived Inactivated COVID-19 Vaccine in Older Patients with Hypertension and Diabetes Mellitus

by Yuntao Zhang, Haiping Chen, Jun Lv, Tao Huang, Ruizhi Zhang, Dongjuan Zhang, Linyun Luo, Sheng Wei, Xiaoqin Liu, Shangxiao Zhang, Qiuyue Mu, Rongdong Huang, Jiao Huang, Yanhui Xiao, Yunkai Yang, Yuting Han, Hao Gong, Qinghu Guan, Fangqin Xie, Hui Wang, Liming Li and Xiaoming Yang Show full author list Hide full author list

Vaccines 2022, 10(7), 1020; https://doi.org/10.3390/vaccines10071020 - 25 Jun 2022

Cited by 12 | Viewed by 2380

Abstract

Background: To evaluate the immunogenicity and safety of the COVID-19 vaccine (Vero cell), inactivated, in a population aged ≥60 years with hypertension or(/and) diabetes mellitus. Methods: A total of 1440 participants were enrolled and divided into four groups, 330 in the hypertension group, [...] Read more.

Background: To evaluate the immunogenicity and safety of the COVID-19 vaccine (Vero cell), inactivated, in a population aged ≥60 years with hypertension or(/and) diabetes mellitus. Methods: A total of 1440 participants were enrolled and divided into four groups, 330 in the hypertension group, 330 in the diabetes group, 300 in the hypertensive combined with diabetes group (combined disease group), and 480 in the healthy population group. Two doses of the COVID-19 vaccine (Vero cell), inactivated, were administered at a 21-day interval and blood samples were collected before vaccination and 28 days after the second dose to evaluate the immunogenicity. The adverse events and changes in blood pressure and blood glucose levels after vaccination were recorded. Results: The seroconversion rate of the COVID-19 neutralizing antibodies was 100% for all participants. The post-inoculation geometric mean titer (GMT) in the four groups of the hypertension, diabetes, combined disease, and healthy populations were 73.41, 69.93, 73.84, and 74.86, respectively. The seroconversion rates and post-vaccination GMT in the hypertension, diabetes, and combined disease groups were non-inferior to the healthy population group. The rates of vaccine-related adverse reactions were 11.93%, 14.29%, 12.50%, and 9.38%, respectively. No serious adverse events were reported during the study. No apparent abnormal fluctuations in blood pressure and blood glucose values were observed after vaccination in participants with hypertension or(/and) diabetes. Conclusions: The COVID-19 vaccine (Vero cell), inactivated, showed good immunogenicity and safety in patients aged ≥60 years suffering from hypertension or(/and) diabetes mellitus. Full article

(This article belongs to the Special Issue Current Use and Development of Vaccines in China)

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10 pages, 435 KiB

Open AccessCommunication

Safety and Immunogenicity of Inactivated Bacillus subtilis Spores as a Heterologous Antibody Booster for COVID-19 Vaccines

by Johnny Chun-Chau Sung, Nelson Cheuk-Yin Lai, Kam-Chau Wu, Man-Chung Choi, Chloe Ho-Yi Ma, Jayman Lin, Cheong-Nang Kuok, Wai-Leng Leong, Weng-Kei Lam, Yusuf Khwaja Hamied, Dominic Man-Kit Lam, Eric Tung-Po Sze and Keith Wai-Yeung Kwong

Vaccines 2022, 10(7), 1014; https://doi.org/10.3390/vaccines10071014 - 24 Jun 2022

Cited by 4 | Viewed by 2230

Abstract

The coronavirus diseases 2019 (COVID-19) pandemic caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infections have threatened the world for more than 2 years. Multiple vaccine candidates have been developed and approved for emergency use by specific markets, but multiple doses are [...] Read more.

The coronavirus diseases 2019 (COVID-19) pandemic caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infections have threatened the world for more than 2 years. Multiple vaccine candidates have been developed and approved for emergency use by specific markets, but multiple doses are required to maintain the antibody level. Preliminary safety and immunogenicity data about an oral dose vaccine candidate using recombinant Bacillus subtilis in healthy adults were reported previously from an investigator-initiated trial in Hong Kong. Additional data are required in order to demonstrate the safety and efficacy of the candidate as a heterologous booster in vaccinated recipients. In an ongoing, placebo-controlled, observer-blinded, fixed dose, investigator-initiated trial conducted in the Macau, we randomly assigned healthy adults, 21 to 62 years of age to receive either placebo or a Bacillus subtilis oral dose vaccine candidate, which expressed the spike protein receptor binding domain of SARS-CoV-2 on the spore surface. The primary outcome was safety (e.g., local and systemic reactions and adverse events); immunogenicity was a secondary outcome. For both the active vaccine and placebo, participants received three courses in three consecutive days. A total of 16 participants underwent randomization: 9 participants received vaccine and 7 received placebo. No observable local or systemic side-effect was reported. In both younger and older adults receiving placebo, the neutralizing antibody levels were gradually declining, whereas the participants receiving the antibody booster showed an increase in neutralizing antibody level. Full article

(This article belongs to the Special Issue Current Use and Development of Vaccines in China)

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11 pages, 1016 KiB

Open AccessArticle

Immunogenicity and Safety of an Inactivated Enterovirus 71 Vaccine Administered Simultaneously with Hepatitis B Virus Vaccine, Group A Meningococcal Polysaccharide Vaccine, Measles-Rubella Combined Vaccine and Japanese Encephalitis Vaccine: A Multi-Center, Randomized, Controlled Clinical Trial in China

by Xiaodong Liu, Shaoying Chang, Ruize Wang, Yanhui Xiao, Fangjun Li, Qing Xu, Shaobai Zhang, Xiao Chen, Shangxiao Zhang, Min Zhang, Xiaoqi Chen, Qingfan Cao, Xiaoyu Liu, Hui Wang, Daihong Zhan, Haiping Chen, Wei Chen, Jianyong Jiang, Chao Zhang, Haijiao Wang, Lidong Gao, Xuanwen Shi, Xiaoming Yang and Aiqiang Xu Show full author list Hide full author list

Vaccines 2022, 10(6), 895; https://doi.org/10.3390/vaccines10060895 - 02 Jun 2022

Cited by 3 | Viewed by 2075

Abstract

Background: The aim of this study was to investigate the immunogenicity and safety of the enterovirus 71 vaccine (EV71 vaccine) administered alone or simultaneously. Methods: A multi-center, open-label, randomized controlled trial was performed involving 1080 healthy infants aged 6 months or 8 months [...] Read more.

Background: The aim of this study was to investigate the immunogenicity and safety of the enterovirus 71 vaccine (EV71 vaccine) administered alone or simultaneously. Methods: A multi-center, open-label, randomized controlled trial was performed involving 1080 healthy infants aged 6 months or 8 months from Shandong, Shanxi, Shaanxi, and Hunan provinces. These infants were divided into four simultaneous administration groups and EV71 vaccine separate administration group. Blood samples were collected from the infants before the first vaccination and after the completion of the vaccination. This trial was registered in the Clinical Trials Registry (NCT03519568). Results: A total of 895 were included in the per-protocol analysis. The seroconversion rates of antibodies against EV71 in four simultaneous administration groups (98.44% (189/192), 94.57% (122/129), 99.47% (187/188) and 98.45% (190/193)) were non-inferior to EV71 vaccine separate administration group (97.93% [189/193]) respectively. Fever was the most common adverse event, the pairwise comparison tests showed no difference in the incidence rate of solicited, systemic or local adverse events. Three serious adverse events related to the vaccination were reported. Conclusions: The evidence of immunogenicity and safety supports that the EV71 vaccine administered simultaneously with vaccines need to be administered during the same period of time recommended in China. Full article

(This article belongs to the Special Issue Current Use and Development of Vaccines in China)

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Review

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13 pages, 619 KiB

Open AccessReview

Past, Present and Future of Bacillus Calmette-Guérin Vaccine Use in China

by Junli Li, Jinbiao Lu, Guozhi Wang, Aihua Zhao and Miao Xu

Vaccines 2022, 10(7), 1157; https://doi.org/10.3390/vaccines10071157 - 20 Jul 2022

Cited by 2 | Viewed by 2722

Abstract

The BCG vaccine is prepared from a weakened strain of Mycobacterium bovis (M. bovis), a bacterium closely related to Mycobacterium tuberculosis (MTB), which causes tuberculosis (TB). The vaccine was developed over 13 years, from 1908 to 1921, in the French Institut [...] Read more.

The BCG vaccine is prepared from a weakened strain of Mycobacterium bovis (M. bovis), a bacterium closely related to Mycobacterium tuberculosis (MTB), which causes tuberculosis (TB). The vaccine was developed over 13 years, from 1908 to 1921, in the French Institut Pasteur by Léon Charles Albert Calmette and Jean-Marie Camille Guérin, who named the product Bacillus Calmette–Guérin (BCG). BCG, the only licensed vaccine currently available to prevent TB, is given to infants at high risk of TB shortly after birth to protect infants and young children from pulmonary, meningeal, and disseminated TB. The BCG vaccine, one of the safest and most widely used live attenuated vaccines in the world, recently celebrated its 100th anniversary (from 1921 to 2021); its record of use in preventing TB in China is also approaching 100 years. In 2022, a new century of BCG vaccine immunization will begin. In this article, we briefly review the history of BCG vaccine use in China, describe its current status, and offer a preliminary outlook on the future of the vaccine, to provide BCG researchers with a clearer understanding of its use in China. Full article

(This article belongs to the Special Issue Current Use and Development of Vaccines in China)

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Other

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6 pages, 230 KiB

Open AccessOpinion

Discussion of the Trust in Vaccination against COVID-19

by Jiangbo Fan, Xi Wang, Shuai Du, Ayan Mao, Haiping Du and Wuqi Qiu

Vaccines 2022, 10(8), 1214; https://doi.org/10.3390/vaccines10081214 - 29 Jul 2022

Cited by 7 | Viewed by 1570

Abstract

The COVID-19 pandemic has introduced serious challenges to global public health security, and the benefits of vaccination via public health interventions have been recognized as significant. Vaccination is an effective means of preventing and controlling the spread of COVID-19. However, trust is a [...] Read more.

The COVID-19 pandemic has introduced serious challenges to global public health security, and the benefits of vaccination via public health interventions have been recognized as significant. Vaccination is an effective means of preventing and controlling the spread of COVID-19. However, trust is a major factor that influences vaccine hesitancy; thus, the distrust of vaccination has hindered the popularization of COVID-19 vaccines. This paper aims to discuss the main problems and the role of trust in the vaccination against COVID-19 to effectively promote and implement policy to promote the acceptance of COVID-19 vaccines. Full article

(This article belongs to the Special Issue Current Use and Development of Vaccines in China)

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