Antibodies Induced by Smallpox Vaccination after at Least 45 Years Cross-React with and In Vitro Neutralize Mpox Virus: A Role for Polyclonal B Cell Activation?

AIMS: To evaluate whether antibodies specific for the vaccinia virus (VV) are still detectable after at least 45 years from immunization. To confirm that VV-specific antibodies are endowed with the capacity to neutralize Mpox virus (MPXV) in vitro. To test a possible role of polyclonal non-specific activation in the maintenance of immunologic memory. METHODS: Sera were collected from the following groups: smallpox-vaccinated individuals with or without latent tuberculosis infection (LTBI), unvaccinated donors, and convalescent individuals after MPXV infection. Supernatant of VV- or MPXV-infected Vero cells were inactivated and used as antigens in ELISA or in Western blot (WB) analyses. An MPXV plaque reduction neutralization test (PRNT) was optimized and performed on study samples. VV- and PPD-specific memory T cells were measured by flow cytometry. RESULTS: None of the smallpox unvaccinated donors tested positive in ELISA or WB analysis and their sera were unable to neutralize MPXV in vitro. Sera from all the individuals convalescing from an MPXV infection tested positive for anti-VV or MPXV IgG with high titers and showed MPXV in vitro neutralization capacity. Sera from most of the vaccinated individuals showed IgG anti-VV and anti-MPXV at high titers. WB analyses showed that positive sera from vaccinated or convalescent individuals recognized both VV and MPXV antigens. Higher VV-specific IgG titer and specific T cells were observed in LTBI individuals. CONCLUSIONS: ELISA and WB performed using supernatant of VV- or MPXV-infected cells are suitable to identify individuals vaccinated against smallpox at more than 45 years from immunization and individuals convalescing from a recent MPXV infection. ELISA and WB results show a good correlation with PRNT. Data confirm that a smallpox vaccination induces a long-lasting memory in terms of specific IgG and that antibodies raised against VV may neutralize MPXV in vitro. Finally, higher titers of VV-specific antibodies and higher frequency of VV-specific memory T cells in LTBI individuals suggest a role of polyclonal non-specific activation in the maintenance of immunologic memory.

Evaluation of the public policy impacts on Monkeypox in Brazil.

Brazil ranked third in the number of Monkeypox infected worldwide in early September 2022 and eighth in multiple deaths. Brazilian Ministry of Health prepared a public policy to face the smallpox outbreak. This paper aims to analyze the governmental public policy' impacts on Monkeypox using survival analysis. The information in the database was collected from epidemiological bulletins on the official websites of the Brazilian Ministry of Health and the World Health Organization (WHO). The survival analysis with parametric statistical analysis, semiparametric with Cox regression, and nonparametric analysis were used. The inference of causality was perceived by the impact caused by the national public policy with the proportional reduction in the number of cases in the treatment group (Chi-sq = 117.783, p < 0.001), contrary to what was perceived in the control group, as well as survival about the time of the states that elaborated their plans based on what was made available by the government. The need to evaluate government projects should be within the scope of project management in Brazilian states and provide for more assertive decision-making in the fight against smallpox.

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.

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.

Orally available nucleoside analog UMM-766 provides protection in a murine model of orthopox disease.

Although smallpox has been eradicated, other orthopoxviruses continue to be a public health concern as exemplified by the ongoing Mpox (formerly monkeypox) global outbreak. While medical countermeasures (MCMs) previously approved by the Food and Drug Administration for the treatment of smallpox have been adopted for Mpox, previously described vulnerabilities coupled with the questionable benefit of at least one of the therapeutics during the 2022 Mpox outbreak reinforce the need for identifying and developing other MCMs against orthopoxviruses. Here, we screened a panel of Merck proprietary small molecules and identified a novel nucleoside inhibitor with potent broad-spectrum antiviral activity against multiple orthopoxviruses. Efficacy testing of a 7-day dosing regimen of the orally administered nucleoside in a murine model of severe orthopoxvirus infection yielded a dose-dependent increase in survival. Treated animals had greatly reduced lesions in the lung and nasal cavity, particularly in the 10 µg/mL dosing group. Viral levels were also markedly lower in the UMM-766-treated animals. This work demonstrates that this nucleoside analog has anti-orthopoxvirus efficacy and can protect against severe disease in a murine orthopox model.IMPORTANCEThe recent monkeypox virus pandemic demonstrates that members of the orthopoxvirus, which also includes variola virus, which causes smallpox, remain a public health issue. While currently FDA-approved treatment options exist, risks that resistant strains of orthopoxviruses may arise are a great concern. Thus, continued exploration of anti-poxvirus treatments is warranted. Here, we developed a template for a high-throughput screening assay to identify anti-poxvirus small-molecule drugs. By screening available drug libraries, we identified a compound that inhibited orthopoxvirus replication in cell culture. We then showed that this drug can protect animals against severe disease. Our findings here support the use of existing drug libraries to identify orthopoxvirus-targeting drugs that may serve as human-safe products to thwart future outbreaks.

Monkeypox: Can we count on the current smallpox immunization?

Two vaccines ACAM 2000 and JYNNEOS have obtained approval from the Food and Drug Administration as preventive measures against monkeypox, contributing significantly to the management of the monkeypox epidemic. Nonetheless, research has demonstrated that smallpox vaccination offers approximately 88.8% protection against monkeypox, while immunization with these vaccines generates relatively low levels of neutralizing antibodies. In this work, we performed a comprehensive comparison of antigens between the 2022-2023 monkeypox strains and the smallpox vaccine strains. Our analysis has revealed considerable amino acid changes in all 27 antigens, including core and envelope proteins. Amino acid substitutions within B cell epitopes were observed in 26 of these antigens, with at least half of the antigen substitutions occurring within B cell epitopes in 20 out of the 26 antigens analyzed. These findings may raise potential concerns regarding the efficacy of these vaccines.

Tracing the journey of poxviruses: insights from history.

The historical significance of the poxviruses is profound, largely due to the enduring impact left by smallpox virus across many centuries. The elimination of smallpox is a remarkable accomplishment in the history of science and medicine, with centuries of devoted efforts resulting in the development and widespread administration of smallpox vaccines. This review provides insight into the pivotal historical events involving medically significant poxviruses. Understanding the remarkable saga of combatting smallpox is crucial, serving as a guidepost for potential future encounters with poxvirus infections. There is a continual need for vigilant observation of poxvirus evolution and spillover from animals to humans, considering the expansive range of susceptible hosts. The recent occurrence of monkeypox cases in non-endemic countries stands as a stark reminder of the ease with which infections can be disseminated through international travel and trade. This backdrop encourages introspection about our journey and the current status of poxvirus research.

Monkeypox: An outbreak of a rare viral disease.

Monkeypox is a viral zoonotic disease rarely found outside Africa. Monkeypox can be spread from person to person through close contact with an infected person, and the rate of transmission is not very high. In addition, monkeypox and variola virus are both pox viruses, and the spread of monkeypox virus was also controlled to some extent by the smallpox campaign, so monkeypox was not widely paid attention to. However, as smallpox vaccination is phased out in various countries or regions, people's resistance to orthopoxviruses is decreasing, especially among people who have not been vaccinated against smallpox. This has led to a significant increase in the frequency and geographical distribution of human monkeypox cases in recent years, and the monkeypox virus has become the orthopoxvirus that poses the greatest threat to public health. Since the last large-scale monkeypox infection was detected in 2022, the number of countries or territories affected has exceeded 100. Many confirmed and suspected cases of monkeypox have been found in individuals who have not travelled to affected areas, and the route of infection is not obvious, making this outbreak of monkeypox a cause for concern globally. The purpose of this systematic review is to further understand the pathophysiological and epidemiological characteristics of monkeypox, as well as existing prevention and treatment methods, with a view to providing evidence for the control of monkeypox.

Residual Immunity from Smallpox Vaccination and Possible Protection from Mpox, China.

Among persons born in China before 1980 and tested for vaccinia virus Tiantan strain (VVT), 28.7% (137/478) had neutralizing antibodies, 71.4% (25/35) had memory B-cell responses, and 65.7% (23/35) had memory T-cell responses to VVT. Because of cross-immunity between the viruses, these findings can help guide mpox vaccination strategies in China.

Human mpox: global trends, molecular epidemiology and options for vaccination.

The eradication of smallpox and the cessation of vaccination have led to the growth of the susceptible human population to poxviruses. This has led to the increasing detection of zoonotic orthopoxviruses. Among those viruses, monkeypox virus (MPV) is the most commonly detected in Western and Central African regions. Since 2022, MPV is causing local transmission in newly affected countries all over the world. While the virus causing the current outbreak remains part of clade II (historically referred to as West African clade), it has a significant number of mutations as compared to other clade II sequences and is therefore referred to as clade IIb. It remains unclear whether those mutations may have caused a change in the virus phenotype. Vaccine effectiveness data show evidence of a high cross-protection of vaccines designed to prevent smallpox against mpox. These vaccines therefore represent a great opportunity to control human-to-human transmission, provided that their availability has short time-frames and that mistakes from the recent past (vaccine inequity) will not be reiterated.

Neutralization Determinants on Poxviruses.

Smallpox was a highly contagious disease caused by the variola virus. The disease affected millions of people over thousands of years and variola virus ranked as one of the deadliest viruses in human history. The complete eradication of smallpox in 1980, a major triumph in medicine, was achieved through a global vaccination campaign using a less virulent poxvirus, vaccinia virus. Despite this success, the herd immunity established by this campaign has significantly waned, and concerns are rising about the potential reintroduction of variola virus as a biological weapon or the emergence of zoonotic poxviruses. These fears were further fueled in 2022 by a global outbreak of monkeypox virus (mpox), which spread to over 100 countries, thereby boosting interest in developing new vaccines using molecular approaches. However, poxviruses are complex and creating modern vaccines against them is challenging. This review focuses on the structural biology of the six major neutralization determinants on poxviruses (D8, H3, A27, L1, B5, and A33), the localization of epitopes targeted by neutralizing antibodies, and their application in the development of subunit vaccines.

[La expedición Balmis en el Suplemento a la Gazeta de Madrid (14 de octubre de 1806), difusión hispana.] / The Balmis expedition in the Supplement to the Gazeta de Madrid (October 14, 1806), Hispanic diffusion.

The Madrid Gazette published a Supplement on October 14, 1806, regarding the arrival of the Director of the Royal Expedition Vaccine Philanthropy, Francisco Xavier Balmis, and the reception held by King Carlos IV. Balmis had completed his journey across the Spanish overseas territories, taking the vaccine against smallpox from arm to arm with the help of a human chain of children. During this journey, Balmis also established Vaccination Boards and endeavoured to identify cows with cowpox. The publication endorsed the policies of a declining Bourbon monarchy and marked the peak of Balmis' professional career. Both sides emerged victorious: the Crown showcased itself as the sponsor and organiser of this altruistic journey, in line with prior scientific expeditions; and Balmis secured his place in Public Health history as the director of the first international vaccination campaign. This did not mean the culmination of the expedition, as other members were still administering vaccinations in the Philippines and South America. The main objective of this study was to assess the importance of the newspaper Madrid Gazette, outline the contents of the publication, authenticate the origins of the documentary sources underpinning its composition, and confirm its impact and citations throughout 19th-century Spanish publications. The components of the publication, its origins, as well as Balmis' involvement in its creation, have been substantiated. The Supplement's importance is defined by its utility as a resource for commemorating and appreciating the expedition.

La Gazeta de Madrid publicó un Suplemento el 14 de octubre de 1806 dando noticia de la llegada y recepción al Director de la Real Expedición Filantrópica de la Vacuna, Francisco Xavier Balmis, por parte del Rey Carlos IV. Había finalizado su periplo dando la vuelta al mundo por los territorios españoles de ultramar, llevando la vacuna contra la viruela brazo a brazo con la ayuda de una cadena humana de niños, creando Juntas de Vacunación e intentando encontrar vacas con cowpox. La publicación refrendó las políticas de una monarquía borbónica en decadencia y significó el momento álgido de la carrera profesional de Balmis. Ambas partes ganaban: la Corona publicitándose como financiadora y organizadora del viaje altruista en línea con expediciones científicas anteriores; Balmis pasando a la historia de la Salud Pública como director de la primera campaña internacional de vacunación. No fue el final de la expedición, ya que el resto de los expedicionarios aún seguían vacunando en Filipinas y América del Sur. El objetivo de este estudio fue analizar la importancia de la Gazeta de Madrid como periódico, describir los contenidos de la noticia, verificar el origen de las fuentes documentales que apoyaron su redacción y comprobar el impacto y citas que tuvo a lo largo del siglo XIX en publicaciones en idioma español. Los componentes de la noticia, su proveniencia, así como la participación de Balmis en su redacción han quedado probados. La importancia del Suplemento estribó en su utilidad como recurso para recordar y poner en valor la expedición.

Cross-reactive antibody response to Monkeypox virus surface proteins in a small proportion of individuals with and without Chinese smallpox vaccination history.

BACKGROUND: After the eradication of smallpox in China in 1979, vaccination with the vaccinia virus (VACV) Tiantan strain for the general population was stopped in 1980. As the monkeypox virus (MPXV) is rapidly spreading in the world, we would like to investigate whether the individuals with historic VACV Tiantan strain vaccination, even after more than 40 years, could still provide ELISA reactivity and neutralizing protection; and whether the unvaccinated individuals have no antibody reactivity against MPXV at all. RESULTS: We established serologic ELISA to measure the serum anti-MPXV titer by using immunodominant MPXV surface proteins, A35R, B6R, A29L, and M1R. A small proportion of individuals (born before 1980) with historic VACV Tiantan strain vaccination exhibited serum ELISA cross-reactivity against these MPXV surface proteins. Consistently, these donors also showed ELISA seropositivity and serum neutralization against VACV Tiantan strain. However, surprisingly, some unvaccinated young adults (born after 1980) also showed potent serum ELISA activity against MPXV proteins, possibly due to their past infection by some self-limiting Orthopoxvirus (OPXV). CONCLUSIONS: We report the serum ELISA cross-reactivity against MPXV surface protein in a small proportion of individuals both with and without VACV Tiantan strain vaccination history. Combined with our serum neutralization assay against VACV and the recent literature about mice vaccinated with VACV Tiantan strain, our study confirmed the anti-MPXV cross-reactivity and cross-neutralization of smallpox vaccine using VACV Tiantan strain. Therefore, it is necessary to restart the smallpox vaccination program in high risk populations.

La expedición Balmis en el Suplementoa la Gazeta de Madrid (14 de octubrede 1806), difusión hispana / he Balmis expedition in the Supplement to the Gazeta de Madrid (October 14, 1806), Hispanic diffusion

Gazeta de Madrid publicó un Suplemento el 14 de octubre de 1806 dando noticia de la llegada y recepción al Director de la Real Expedición Filantrópica de la Vacuna, Francisco Xavier Balmis, por parte del Rey Carlos IV. Había finalizado su periplo dando la vuelta al mundo por los territorios españoles de ultramar, llevando la vacuna contra la viruela brazo a brazo con la ayuda de una cadena humana de niños, creando Juntas de Vacunación e intentando encontrar vacas concowpox. La publicación refrendó las políticas de una monarquía borbónica en decadencia y significó el momento álgido de la carrera profesional de Balmis. Ambas partes ganaban: la Corona publicitándose como financiadora y organizadora del viaje altruista en línea con expediciones científicas anteriores; Balmis pasando a la historia de la Salud Pública como director de la primera campaña internacional de vacunación. No fue el final de la expedición, ya que el resto de los expedicionarios aún seguían vacunando en Filipinas y América del Sur. El objetivo de este estudio fue analizar la importancia de la Gazeta de Madrid como periódico, describir los contenidos de la noticia, verificar el origen de las fuentes documentales que apoyaron su redacción y comprobar el impacto y citas que tuvo a lo largo del siglo XIX en publicaciones en idioma español. Los componentes de la noticia, su proveniencia, así como la participación de Balmis en su redacción han quedado probados. La importancia del Suplemento estribó en su utilidad como recurso para recordar y poner en valor la expedición.(AU)

The Madrid Gazette published a Supplement on October 14, 1806, regarding the arrival of the Director of the Royal Expedition Vaccine Philanthropy, Francisco Xavier Balmis, and the reception held by King Carlos IV. Balmis had completed his journey across the Spanish overseas territories, taking the vaccine against smallpox from arm to arm with the help of a human chain of children. During this journey, Balmis also established Vaccination Boards and endeavoured to identify cows with cowpox. The publication endorsed the policies of a declining Bourbon monarchy and marked the peak of Balmis’ professional career. Both sides emerged victorious: the Crown showcased itself as the sponsor and organiser of this altruistic journey, in line with prior scientific expeditions; and Balmis secured his place in Public Health history as the director of the first international vaccination campaign. This did not mean the culmination of the expedition, as other members were still administering vaccinations in the Philippines and South America. The main objective of this study was to assess the importance of the newspaper Madrid Gazette, outline the contents of the publication, authenticate the origins of the documentary sources underpinning its composition, and confirm its impact and citations throughout 19 th -century Spanish publications. The components of the publication, its origins, as well as Balmis’ involvement in its creation, have been substantiated. The Supplement’s importance is defined by its utility as a resource for commemorating and appreciating the expedition.(AU)

Monkeypox virus-infected individuals mount comparable humoral immune responses as Smallpox-vaccinated individuals.

In early 2022, a cluster of monkeypox virus (MPXV) infection (mpox) cases were identified within the UK with no prior travel history to MPXV-endemic regions. Subsequently, case numbers exceeding 80,000 were reported worldwide, primarily affecting gay, bisexual, and other men who have sex with men (GBMSM). Public health agencies worldwide have offered the IMVANEX Smallpox vaccination to these individuals at high-risk to provide protection and limit the spread of MPXV. We have developed a comprehensive array of ELISAs to study poxvirus-induced antibodies, utilising 24 MPXV and 3 Vaccinia virus (VACV) recombinant antigens. Panels of serum samples from individuals with differing Smallpox-vaccine doses and those with prior MPXV infection were tested on these assays, where we observed that one dose of Smallpox vaccination induces a low number of antibodies to a limited number of MPXV antigens but increasing with further vaccination doses. MPXV infection induced similar antibody responses to diverse poxvirus antigens observed in Smallpox-vaccinated individuals. We identify MPXV A27 as a serological marker of MPXV-infection, whilst MPXV M1 (VACV L1) is likely IMVANEX-specific. Here, we demonstrate analogous humoral antigen recognition between both MPXV-infected or Smallpox-vaccinated individuals, with binding to diverse yet core set of poxvirus antigens, providing opportunities for future vaccine (e.g., mRNA) and therapeutic (e.g., mAbs) design.

Smallpox Prevention and Public Healthcare in China in the 1920s and 1930s: Focusing on the Cases of Shanghai and Beijing.

Beijing and Shanghai, representative modern cities in China, witnessed the development of various urban infrastructures and quarantine systems in the 1920s and 1930s. Both cities established Health Demonstration Stations in the 1930s, as part of their implementation of modern health administration. This foundation played a pivotal role for making health administration more practical. Huang Zi-fang (1899-1940) and Hu Hung-ji (1894-1932), the inaugural directors of the health bureau in the respective cities, were both graduates of the Johns Hopkins University School of Public Health in the United States. They shared a similar view of public health. Active exchanges occurred between the heads of the health administration in the two cities who were the leading forces in the health reform, encompassing various health experiments including the Health Demonstration Station. During the 1930s in China, state medicine gained prominence as the most ideal medical model for constructing a modern state. As such, the quarantine activities they promoted were also considered the most ideal model. The public health care centered on Health Demonstration Stations in the 1920s and 1930s that developed in large Chinese cities such as Beijing and Shanghai pursued similar goals by strengthening quarantine administration through free medical treatment and modern spatial control. Nonetheless, each city exhibited differences in terms of the subjects and targets of quarantine, as well as the primary bases of quarantine, which were either Health Demonstration Stations or hospitals. Both municipal governments and the civilian sector led the sanitary infrastructure development. While Shanghai showed stronger development in terms of the number of vaccinations, Shanghai's dualized quarantine system did not necessarily create a better health environment than Beijing in terms of spatial control. In the 1940s, the Japanese occupation government implemented measures to inherit and further develop existing health administrations in Beijing and Shanghai. Existing international settlements were incorporated into the Japanese occupation government, and the occupation government pursued homogenization of urban space and tried to maintain the existing urban policy as much as possible to preserve the status quo. However, the intensification of the Anti-Japanese War and the Chinese Civil War brought an end to the health experiment centered around the Health Demonstration Station in China in the first half of the twentieth century.