The 5 C model and Mpox vaccination behavior in Germany: a cross-sectional survey.

BACKGROUND: Due to the authorization of the Mpox vaccines, we aimed to identify determinants of the intention to get vaccinated, actively trying to receive vaccination, and for successfully receiving a vaccination in Germany employing the 5 C model of vaccination readiness. METHODS: Data stem from a cross-sectional online survey that was available online from August 13, 2022 to August 31, 2022. To assess the influence of the 5 C Model on vaccination behavior, we conducted a multinomial logistic regression. RESULTS: 3,338 participants responded to the survey, with 487 already vaccinated and 2,066 intending to receive a vaccination. Confidence and collective responsibility were positively associated with intention to get vaccinated, while complacency was negatively correlated. A higher score on the calculation scale increased the odds of intention to receive vaccination but not with actively having tried to receive a vaccination. Fewer perceived constraints were associated with higher odds to be vaccinated. Patients in practices that focus on HIV treatment were more likely to intend to get vaccinated, to have tried to get vaccinated and to be vaccinated, regardless of indication. While level of education had no impact, having an indication to get vaccinated was a strong predictor of vaccination behavior in all groups. CONCLUSION: Future vaccination campaigns should aim to reduce specific constraints of the target group and make vaccines widely available in primary care institutions beyond HIV-focused practices.

Lot-to-lot consistency, immunogenicity, and safety of the Ad26.ZEBOV, MVA-BN-Filo Ebola virus vaccine regimen: A phase 3, randomized, double-blind, placebo-controlled trial.

This phase-3, double-blind, placebo-controlled study (NCT04228783) evaluated lot-to-lot consistency of the Ad26.ZEBOV, MVA-BN-Filo Ebola vaccine regimen. Participants were randomized (6:6:6:1) to receive the two-dose regimen from three consecutively manufactured lots of Ad26.ZEBOV on Day 1 paired with three consecutively manufactured lots of MVA-BN-Filo on Day 57 (Groups 1-3) or two doses of placebo (Group 4). An additional cohort also received an Ad26.ZEBOV booster or placebo 4 months post-dose 2. Equivalence of the immunogenicity at 21 days post-dose 2 between any two groups was demonstrated if the 95% confidence interval (CI) of the Ebola virus glycoprotein (EBOV GP)-binding antibody geometric mean concentration (GMC) ratio was entirely within the prespecified margin of 0.5-2.0. Lot-to-lot consistency (i.e., consecutive lots can be consistently manufactured) was accomplished if equivalence was shown for all three pairwise comparisons. Results showed that the primary objective in the per-protocol immunogenicity subset (n = 549) was established for each pairwise comparison (Group 1 vs 2: GMC ratio = 0.9 [95% CI: 0.8, 1.1], Group 1 vs 3: 0.9 [0.8, 1.1], Group 2 vs 3: 1.0 [0.9, 1.2]). Equivalence of the three groups for the Ad26.ZEBOV component only was also demonstrated at 56 days post-dose 1. EBOV GP-binding antibody responses (post-vaccination concentrations >2.5-fold from baseline) were observed in 419/421 (99.5%) vaccine recipients at 21 days post-dose 2 and 445/460 (96.7%) at 56 days post-dose 1. In the booster cohort (n = 39), GMCs increased 9.0- and 11.8-fold at 7 and 21 days post-booster, respectively, versus pre-booster. Ad26.ZEBOV, MVA-BN-Filo was well tolerated, and no safety issues were identified.

Comparison of the immunogenicity and protective efficacy of ACAM2000, MVA, and vectored subunit vaccines for Mpox in rhesus macaques.

The 2022-2023 mpox outbreak triggered vaccination efforts using smallpox vaccines that were approved for mpox, including modified vaccinia Ankara (MVA; JYNNEOS), which is a safer alternative to live replicating vaccinia virus (ACAM2000). Here, we compare the immunogenicity and protective efficacy of JYNNEOS by the subcutaneous or intradermal routes, ACAM2000 by the percutaneous route, and subunit Ad35 vector-based L1R/B5R or L1R/B5R/A27L/A33R vaccines by the intramuscular route in rhesus macaques. All vaccines provided robust protection against high-dose intravenous mpox virus challenge with the current outbreak strain, with ACAM2000 providing near complete protection and JYNNEOS and Ad35 vaccines providing robust but incomplete protection. Protection correlated with neutralizing antibody responses as well as L1R/M1R- and B5R/B6R-specific binding antibody responses, although additional immune responses likely also contributed to protection. This study demonstrates the protective efficacy of multiple vaccine platforms against mpox virus challenge, including both current clinical vaccines and vectored subunit vaccines.

Influences of mpox disease perceptions, sources and contents of information exposure on mpox vaccine uptake among gay, bisexual, and other men who have sex with men in Hong Kong, China.

BACKGROUND: Following the global mpox outbreak in 2022, multiple regions in Asia have been reporting ongoing mpox cases within high-risk groups, including gay, bisexual, and other men who have sex with men (GBMSM). An optimal level of vaccination rate is essential to prevent further mpox outbreaks. However, no existing studies have examined mpox vaccine uptake among GBMSM in East Asia. METHODS: A cross-sectional survey was conducted among a sample of 531 GBMSM in Hong Kong, China, between March and October 2023. The study used multivariable logistic regression models to investigate the associations between mpox-related disease perceptions, exposures to sources and contents of mpox-related information, and mpox vaccine uptake. RESULTS: The prevalence of mpox vaccine uptake among GBMSM in Hong Kong was 21.7%, with 7.7% completing one dose and 13.9% completing two doses. GBMSM who were younger or earning less monthly income were less likely to have been vaccinated. After adjusting for confounding variables, participants who perceived more negative impacts on their lives if they were to contract mpox, more severe symptoms, and a more coherent understanding of mpox were positively associated with mpox vaccine uptake. In addition, more frequent exposure to information through the following sources: TV, newspaper, radio and posters, government websites, news websites or apps, other people's social media, and communication over the phone or face-to-face was positively associated with mpox vaccine uptake. Finally, more frequent exposure to the following information contents: mpox statistics from other countries, the Hong Kong government's responses to mpox cases, negative information about patients with mpox, and information on prevention and treatment of mpox were positively associated with mpox vaccine uptake. CONCLUSIONS: This study provides timely and evidence-based implications to address health communication and messaging needs in promoting mpox vaccination among GBMSM in Hong Kong, relevant to regions with similar sociocultural contexts.

A theory-based assessment of mpox: Findings from a nationally representative survey of U.S. adults.

The purpose of this research was to examine individual differences related to fear of, perceived susceptibility to, and perceived severity of mpox as well as mpox knowledge, fear, perceived susceptibility, and perceived severity as predictors of vaccine intention in a national survey of U.S. adults (aged ≥18 years). Address-based sampling (ABS) methods were used to ensure full coverage of all households in the nation, reflecting the 2021 March Supplement of the Current Population Survey. Internet-based surveys were self-administered by Ipsos between September 16-26, 2022. N = 1018 participants completed the survey. The survey included items, based partially on the Health Belief Model, assessing vaccine intention (1 item; responses from 1 [Definitely not] to 5 [Definitely]), fear of mpox (7-item scale; α = .89; theoretical mean = 7-35), perceived susceptibility to mpox (3-item scale; α = .85; theoretical mean = 3-15), and perceived severity of mpox (4-item scale; α = .65; theoretical mean = 4-20). Higher scores indicate greater fear, susceptibility, and severity. One-way ANOVAs were run to examine mean score differences by demographic groups (e.g., gender, race/ethnicity, sexual orientation), and multiple regression analyses assessed the relationship between predictors (mpox knowledge, susceptibility/severity, fear) and a single outcome (vaccination intention), while controlling for demographic covariates. Sampling weights were applied to all analyses. Only 1.8% (n = 18) of respondents reported having received the mpox vaccine. While mpox vaccine intention was low (M = 2.09, SD = 0.99), overall differences between racial/ethnic, sexual orientation, education, and household income groups were statistically significant. Fear of mpox was very low (M = 13.13, SD = 5.33), and there were overall statistically significant differences in both fear and perceived severity among gender, race/ethnicity, sexual orientation, education, and household income groups. While respondents reported not feeling very susceptible to mpox (M = 5.77, SD = 2.50), they generally rated mpox as just above the theoretical mean in terms of severity (M = 11.01, SD = 2.85). Mpox knowledge, fear, severity, and susceptibility, as well as race/ethnicity, were all statistically significant predictors of intention to vaccinate, with susceptibility representing the strongest predictor. Overall, Americans' vaccination for mpox/vaccine intent was low. Gay/lesbian and racial/ethnic minority respondents felt more susceptible to and viewed mpox more severely, compared with heterosexual and White respondents, respectively. These data may be used to tailor risk and prevention (e.g., vaccination) interventions, as cases continue to surge in the current global mpox outbreak. Greater perceptions of susceptibility, severity, and fear about mpox exist largely among minority populations. While public health messaging to promote mpox vaccination can focus on improving knowledge, as well as addressing fear and perceived severity of, and susceptibility to, mpox, such messages should be carefully crafted to prevent disproportionate negative effects on marginalized communities.

Breakthrough cases of mpox: One-dose vaccination is associated with milder clinical manifestations.

BACKGROUND: Very few studies have investigated the effectiveness of vaccination in decreasing the severity of breakthrough mpox. Our goal was to estimate the strength of the associations between recent mpox vaccination with MVA-BN and various clinical manifestations of the disease. METHODS: Telephone interviews using standardized questionnaires, upon notification and 28 days later, of the 403 persons with mpox reported to Montreal Public Health in 2022. MVA-BN vaccination data were obtained from the provincial immunization registry. The main outcomes were numbers of skin lesions and body sites affected, other clinical manifestations (OCM) compatible with mpox, complications, and hospitalization. FINDINGS: 155 persons with mpox (39% of 403) had received 1 dose of vaccine at least 14 days before symptom onset. One-dose vaccination, adjusting for age and HIV status, was significantly associated with fewer lesions, sites affected with lesions, and OCMs. HIV-positive persons with breakthrough mpox reported significantly more lesions, sites affected, and OCMs at initial interview, than HIV-negative ones. However, vaccination was associated with a lower risk of all outcomes to the same degree irrespective of HIV status. INTERPRETATION: One dose of MVA-BN vaccine was about 60% effective in decreasing the frequency and extent of clinical manifestations, among both HIV-positive and HIV-negative persons with breakthrough mpox. Beyond preventing infection, mpox vaccination can be promoted to reduce clinical manifestations in persons at risk for mpox, even if HIV+ . FUNDING: This work used data obtained as part of Montreal Public Health's 2022 mpox outbreak response and received no external funding.

mRNA-based monkeypox virus vaccine prevents disease in non-human primates.

The mpox outbreak in 2022 launched a vaccination campaign employing an existing vaccine with moderate protection, highlighting the lack of scalable Orthopoxvirus vaccines with optimal protection. In this issue of Cell, Zuiani et al. report pre-clinical findings of an mRNA-based mpox vaccine, paving the way for Phase I/II clinical trials.

An overview on mRNA-based vaccines to prevent monkeypox infection.

The human monkeypox virus (Mpox) is classified as a member of the Poxviridae family and belongs to the Orthopoxvirus genus. Mpox possesses double-stranded DNA, and there are two known genetic clades: those originating in West Africa and the Congo Basin, commonly known as Central African clades. Mpox may be treated with either the vaccinia vaccination or the therapeutics. Modifying the smallpox vaccine for treating and preventing Mpox has shown to be beneficial because of the strong link between smallpox and Mpox viruses and their categorization in the same family. Cross-protection against Mpox is effective with two Food and Drug Administration (FDA)-approved smallpox vaccines (ACAM2000 and JYNNEOSTM). However, ACAM2000 has the potential for significant adverse effects, such as cardiac issues, whereas JYNNEOS has a lower risk profile. Moreover, Mpox has managed to resurface, although with modified characteristics, due to the discontinuation and cessation of the smallpox vaccine for 40 years. The safety and efficacy of the two leading mRNA vaccines against SARS-CoV-2 and its many variants have been shown in clinical trials and subsequent data analysis. This first mRNA treatment model involves injecting patients with messenger RNA to produce target proteins and elicit an immunological response. High potency, the possibility of safe administration, low-cost manufacture, and quick development is just a few of the benefits of RNA-based vaccines that pave the way for a viable alternative to conventional vaccines. When protecting against Mpox infection, mRNA vaccines are pretty efficient and may one day replace the present whole-virus vaccines. Therefore, the purpose of this article is to provide a synopsis of the ongoing research, development, and testing of an mRNA vaccine against Mpox.

Behavioral Intention of Receiving Monkeypox Vaccination and Undergoing Monkeypox Testing and the Associated Factors Among Young Men Who Have Sex With Men in China: Large Cross-Sectional Study.

BACKGROUND: The worldwide human monkeypox (mpox) outbreak in 2022 mainly affected men who have sex with men (MSM). In China, young men who have sex with men (YMSM) were at a potential high risk of mpox infection due to their sexual activeness and the eased COVID-19 restrictions at the end of 2022. OBJECTIVE: This study aimed to investigate the behavioral intention of receiving mpox vaccination and undergoing mpox testing in 4 different scenarios and explore their associations with background and behavioral theory-related factors among Chinese YMSM. METHODS: An online cross-sectional survey was conducted among YMSM aged 18-29 years from 6 representative provinces of China in September 2022. Participants recruited (recruitment rate=2918/4342, 67.2%) were asked to self-administer an anonymous questionnaire designed based on prior knowledge about mpox and classic health behavior theories. Data on the participants' background, mpox knowledge and cognition, mpox vaccination and testing cognition, and the behavioral intention of receiving mpox vaccination and undergoing mpox testing were collected. Descriptive analysis and univariate and multivariate linear regressions were performed. Geodetector was used to measure the stratified heterogeneity of behavioral intention. RESULTS: A total of 2493 YMSM with a mean age of 24.6 (SD 2.9) years were included. The prevalence of having a behavioral intention of receiving mpox vaccination ranged from 66.2% to 88.4% by scenario, varying in epidemic status and cost. The prevalence of having an mpox testing intention was above 90% in all scenarios regardless of the presence of symptoms and the cost. The positive factors related to vaccination intention included mpox knowledge (ba=0.060, 95% CI 0.016-0.103), perceived susceptibility of mpox (ba=0.091, 95% CI 0.035-0.146), perceived severity of mpox (ba=0.230, 95% CI 0.164-0.296), emotional distress caused by mpox (ba=0.270, 95% CI 0.160-0.380), perceived benefits of mpox vaccination (ba=0.455, 95% CI 0.411-0.498), self-efficacy of mpox vaccination (ba=0.586, 95% CI 0.504-0.668), and having 1 male sex partner (ba=0.452, 95% CI 0.098-0.806), while the negative factor was perceived barriers to vaccination (ba=-0.056, 95% CI -0.090 to -0.022). The positive factors related to testing intention were perceived severity of mpox (ba=0.283, 95% CI 0.241-0.325), perceived benefits of mpox testing (ba=0.679, 95% CI 0.636-0.721), self-efficacy of mpox testing (ba=0.195, 95% CI 0.146-0.245), having 1 male sex partner (ba=0.290, 95% CI 0.070-0.510), and having in-person gatherings with MSM (ba=0.219, 95% CI 0.072-0.366), while the negative factor was emotional distress caused by mpox (ba=-0.069, 95% CI -0.137 to -0.001). CONCLUSIONS: Among Chinese YMSM, the intention of undergoing mpox testing is optimal, while the mpox vaccination intention has room for improvement. A future national response should raise YMSM's mpox knowledge, disseminate updated information about mpox and preventive measures, improve preventive service accessibility and privacy, and provide advice on positively coping with the associated emotional distress.

Adverse Reactions After Intradermal Vaccination With JYNNEOS for Mpox in Korea.

In response to the Mpox domestic epidemic, South Korea initiated a nationwide vaccination program in May 2023, administering a 0.1 mL intradermal dose of JYNNEOS (Modified Vaccinia Ankara vaccine, Bavarian Nordic) to a high-risk group. To investigate the adverse reactions after intradermal JYNNEOS vaccination, an anonymous online survey was conducted at the National Medical Center from May 22 to July 31, 2023. Overall, 142 individuals responded. Over 80% of the respondents reported local reactions of predominantly mild severity. The predominant local reactions were pruritus, redness, and swelling; their incidence rates after the first dose were 66.2%, 48.1%, and 49.4%, respectively; the corresponding rates after the second dose were 69.2%, 60.6%, and 53.8%. Fewer respondents reported systemic symptoms. The most common systemic symptom was fatigue, the incidence rates of which after the first and second doses were 37.7% and 24.6%, respectively. Overall, the intradermally administered JYNNEOS vaccine appeared well tolerated.

Adverse drug reaction profile of third-generation smallpox vaccines used in France during the 2022 monkeypox epidemic.

Due to the start of the monkeypox epidemic in 2022, we retrospectively analyzed the adverse drug reactions (ADRs) reported in France after monkeypox vaccinations with the third-generation smallpox vaccine. Ninety-eight cases, representing 172 ADRs, were reported. ADRs were mostly expected reactogenicity reactions occurring within days after the first dose of vaccine and having a quick favorable outcome. Unexpected facial palsy and vaccination failure are discussed.

Mpox Neutralizing Antibody Response to LC16m8 Vaccine in Healthy Adults.

Mpox Neutralizing Antibody Response to LC16m8 VaccineIn this study of 50 healthy volunteers in Japan, a smallpox vaccine (LC16m8) exhibited a robust neutralizing antibody response against two strains of the mpox virus. With a 94% "take" rate by day 14, seroconversion rates on day 28 were 72 and 70% against the Zr599 and Liberia strains, respectively, decreasing to 30% for both on day 168; no serious adverse events occurred.

A multivalent mRNA monkeypox virus vaccine (BNT166) protects mice and macaques from orthopoxvirus disease.

In response to the 2022 outbreak of mpox driven by unprecedented human-to-human monkeypox virus (MPXV) transmission, we designed BNT166, aiming to create a highly immunogenic, safe, accessible, and scalable next-generation vaccine against MPXV and related orthopoxviruses. To address the multiple viral forms and increase the breadth of immune response, two candidate multivalent mRNA vaccines were evaluated pre-clinically: a quadrivalent vaccine (BNT166a; encoding the MPXV antigens A35, B6, M1, H3) and a trivalent vaccine (BNT166c; without H3). Both candidates induced robust T cell responses and IgG antibodies in mice, including neutralizing antibodies to both MPXV and vaccinia virus. In challenge studies, BNT166a and BNT166c provided complete protection from vaccinia, clade I, and clade IIb MPXV. Furthermore, immunization with BNT166a was 100% effective at preventing death and at suppressing lesions in a lethal clade I MPXV challenge in cynomolgus macaques. These findings support the clinical evaluation of BNT166, now underway (NCT05988203).

Breakthrough infection and reinfection in patients with mpox.

Recently, patients with Mpox breakthrough infection or reinfection were constantly reported. However, the induction, risk factors, and important clinical symptoms of breakthrough infection and reinfection of Mpox virus (MPXV), as well as the factors affecting the effectiveness of Mpox vaccine are not characterized. Herein, a literature review was preformed to summarize the risk factors and important clinical symptoms of patients with Mpox breakthrough infection or reinfection, as well as the factors affecting the effectiveness of smallpox vaccine against Mpox. Results showed that MSM sexual behavior, condomless sexual behavior, multiple sexual partners, close contact, HIV infection, and the presence of comorbidity are important risk factors for Mpox breakthrough infection and reinfection. Genital ulcers, proctitis, and lymphadenopathy are the important clinical symptoms of Mpox breakthrough infection and reinfection. The effectiveness of emergent vaccination of smallpox vaccine for post-exposure of MPXV is associated with smallpox vaccination history, interval between exposure and vaccination, and history of HIV infection. This review provides a better understanding for the risk factors and important clinical symptoms of Mpox breakthrough infection and reinfection, as well as the formulation of Mpox vaccine vaccination strategies.

A survey-based assessment of rates and covariates of mpox diagnosis and vaccination provides evidence to refine eligibility criteria for mpox vaccination among gay, bisexual and other men who have sex with men in the Netherlands.

Background: The 2022 multicountry mpox outbreaks predominantly affected gay, bisexual and other men who have sex with men (GBMSM) in non-endemic countries, including in the Netherlands. We conducted a survey-based assessment of the alignment between the risk factors associated with mpox diagnosis among GBMSM in the Netherlands and the eligibility criteria used in 2022 for vaccinating this group, with the aim to refine these criteria. Methods: An online self-report survey was conducted among adult GBMSM in the Netherlands between 29 July and 30 August 2022, corresponding to the first month of the Dutch mpox vaccination campaign. GBMSM were recruited via advertisements on social media and gay dating apps. Participants reported on their sexual behaviour, mpox diagnosis, and/or (initial) mpox vaccination since the start of the outbreak. Covariables of mpox diagnosis and vaccination were assessed using logistic regression analyses. Results: Of the 2,460 participants, 73 (3.0%, 95% CI 2.3-3.6%) were diagnosed with mpox and 485 (19.7%, 95% CI 18.1-21.3%) had received (initial) mpox vaccination. Using sample weighting, we estimated that, of the GBMSM population aged 18-80 years in the Netherlands, 1.1% (95% CI 0.7-1.6%) had been diagnosed with mpox and 7.8% (95% CI 6.8-8.9%) had received (initial) vaccination. HIV-PrEP use, living with HIV, reporting ≥20 sex partners in the past 12 months, and sex in sex venues/parties in the past 2 months were independent risk factors for mpox diagnosis. Except for sex in sex venues/parties, these variables were also independently associated with mpox vaccination. Conclusion: This study provides novel evidence regarding the degree to which the 2022 eligibility criteria for mpox vaccination align with the risk factors for mpox among GBMSM in the Netherlands. The findings contribute to a refinement of the eligibility criteria for mpox vaccination, to which sex in sex venues/parties should be added.

A cross-sectional investigation of factors influencing mpox vaccine hesitancy for students in Southwest China.

From July to September 2023, China reported over 1, 400 confirmed cases of mpox transmitted mainly through sexual contact between males. Meanwhile, the percentage of men who have sex with men at universities in southwestern China is increasing every year, which is likely to lead to a potential spread of mpox on campuses. Vaccination is an effective preventive measure against infectious diseases, this study examined the willingness of university students in Southwest China to receive the mpox vaccine and analyzed the factors influencing their decision. A cross-sectional survey was conducted among 7311 university students from 10 universities in Southwest China between August 13 and September 1, 2023. The survey revealed a hesitancy rate of 56.13% toward the mpox vaccine, with the most common reason being concerns about vaccine safety (1407/4104, 34.29%). Univariate analysis identified 13 variables that significantly differed between the vaccine acceptance and vaccine hesitancy groups. Multivariate logistic regression analyses indicated protective factors for vaccine hesitancy, such as sexually transmitted diseases, previous knowledge about mpox, frequent information about mpox, people can get reinfection of mpox, and worries about mpox endemic in China. Additionally, the confidence and convenience dimensions in the 3Cs model were identified as risk factors for mpox vaccine hesitancy. This study found a high rate of vaccine hesitancy among university students in Southwest China regarding the mpox vaccine. Collaboration between university and healthcare departments is recommended to address mpox vaccine hesitancy among college students, thereby promoting their willingness to receive the mpox vaccine.

Willingness to accept monkeypox vaccine and its correlates among men who have sex with men in Southern China: a web-based online cross-sectional study.

Background: The May 2022 global outbreak of monkeypox (MPX) poses a threat to the health of men who have sex with men. However, there is limited data on the willingness of MSM to receive monkeypox vaccination in Southern China. This study aimed to assess the knowledge of MPX, concerns regarding MPX, and willingness to receive monkeypox vaccination, as well as their correlates, among MSM in China. Methods: We conducted a Web-based online survey of MSM in Southern China from August to September 2022. Data were collected on the socio-demographic characteristics, knowledge, worries, concerns regarding MPX and willingness to receive monkeypox vaccination. Multivariate logistic regression was employed to explore the factors associated with willingness to receive monkeypox vaccination. Results: A total of 1903 participants completed the survey. Among them, approximately 69.9% reported being aware of MPX awareness, 94.1% of the participants supported the promotion of monkeypox vaccination. The majority of participants (91.4%) expressed their willingness to receive monkeypox vaccination. Participants who considered monkeypox vaccination safe [adjusted odds ratio (aOR) = 4.82, 95% CI: 1.35-17.18], agreed on the necessity of government promotion of monkeypox vaccination in China (aOR = 6.03, 95% CI: 1.07-33.93), believed in prioritizing monkeypox vaccination for MSM (aOR = 5.01, 95% CI: 1.10-22.71), and had friends or sexual partners who had already received the monkeypox or smallpox vaccination (aOR = 10.37, 95% CI: 2.11-50.99) are more likely to be vaccinated. Conversely, married individuals (aOR = 0.13, 95% CI: 0.03-0.47), those engaging in anal sex 4-6 times per week in the past 3 months (aOR = 0.26, 95% CI: 0.09-0.77) expressed hesitancy toward monkeypox vaccination. Conclusion: There was a high willingness to receive monkeypox vaccination among MSM in China. The hesitancy toward the monkeypox vaccine can be effectively mitigated by addressing concerns about its safety and potential adverse reactions. Moreover, increasing acceptance of the monkeypox vaccination among MSM and their peers is crucial, as social influence significantly impacts vaccine attitudes and behaviors.

Live attenuated smallpox vaccine candidate (KVAC103) efficiently induces protective immune responses in mice.

Smallpox, caused by the variola virus belonging to the genus Orthopoxvirus, is an acute contagious disease that killed 300 million people in the 20th century. Since it was declared to be eradicated and the national immunization program against it was stopped, the variola virus has become a prospective bio-weapon. It is necessary to develop a safe vaccine that protects people from terrorism using this biological weapon and that can be administered to immunocompromised people. Our previous study reported on the development of an attenuated smallpox vaccine (KVAC103). This study evaluated cellular and humoral immune responses to various doses, frequencies, and routes of administration of the KVAC103 strain, compared to CJ-50300 vaccine, and its protective ability against the wild-type vaccinia virus Western Reserve (VACV-WR) strain was evaluated. The binding and neutralizing-antibody titers increased in a concentration-dependent manner in the second inoculation, which increased the neutralizing-antibody titer compared to those after the single injection. In contrast, the T-cell immune response (interferon-gamma positive cells) increased after the second inoculation compared to that of CJ-50300 after the first inoculation. Neutralizing-antibody titers and antigen-specific IgG levels were comparable in all groups administered KVAC103 intramuscularly, subcutaneously, and intradermally. In a protective immunity test using the VACV-WR strain, all mice vaccinated with CJ-50300 or KVAC103 showed 100% survival. KVAC103 could be a potent smallpox vaccine that efficiently induces humoral and cellular immune responses to protect mice against the VACV-WR strain.

Mpox vaccine acceptance among healthcare workers: a systematic review and meta-analysis.

INTRODUCTION: Mpox is a zoonotic viral disease that emerged in May 2022 and has since shown a high prevalence in non-mpox-endemic areas, resulting in an outbreak that caused more than 84,000 cases in 110 countries around the globe. Several vaccines are available to prevent the disease, and multiple studies have been conducted to assess the attitudes of different populations toward receiving the mpox vaccine. This study systematically reviews all the studies conducted on mpox vaccine acceptance/hesitancy among healthcare workers. METHODS: A systematic literature search was conducted through four electronic databases, including PubMed, Scopus, Web of Science, and Google Scholar, up to March 2023. Studies that described mpox vaccine acceptance/hesitancy among healthcare workers were included, and the data were extracted using a uniform extraction sheet. Following the extraction, the meta-analysis included ten studies with 7322 healthcare workers. Three researchers independently assessed the risk of bias in the included study using the Newcastle-Ottawa Scale (NOS). RESULTS: Ten studies were included in the review. This review indicates that the prevalence of mpox vaccine acceptance was 58.5%, and the prevalence of mpox vaccine hesitancy was 41.5%. There was a higher prevalence of acceptance in countries located in Asian and African areas compared to those in North America and Europe, estimated at 68% and 44.3%, respectively. Among the studies conducted solely among physicians, there was a high prevalence of mpox vaccine acceptance, at 77.1%, compared to 49% in studies that included all healthcare workers. CONCLUSION: There is a significant variation in the prevalence of mpox vaccine acceptance among different populations. Further research is needed to identify the factors that contribute to this variation and to develop interventions to increase vaccine acceptance. In addition, it is important to promote research on mpox vaccine acceptance and hesitancy among healthcare workers in countries where data is limited. This research will help policymakers develop effective policies to increase acceptance and reduce the disease burden.