Virulence differences of mpox (monkeypox) virus clades I, IIa, and IIb.1 in a small animal model

Mpox virus Clade IIb infected Cynomolgus macaques via mimic natural infection routes closely resembled human mpox infection

Generating an infectious non-human primate (NHP) model using a prevalent monkeypox virus (MPXV) strain has emerged as a crucial strategy for assessing the efficacy of vaccines and antiviral drugs against human MPXV infection. Here, we established an animal model by infecting cynomolgus macaques with the prevalent MPXV strain, WIBP-MPXV-001, and simulating its natural routes of infection. A comprehensive analysis and evaluation were conducted on three animals, including monitoring clinical symptoms, collecting hematology data, measuring viral loads, evaluating cellular and humoral immune responses, and examining histopathology. Our findings revealed that initial skin lesions appeared at the inoculation sites and subsequently spread to the limbs and back, and all infected animals exhibited bilateral inguinal lymphadenopathy, eventually leading to a self-limiting disease course. Viral DNA was detected in post-infection blood, nasal, throat, rectal and blister fluid swabs. These observations indicate that the NHP model accurately reflects critical clinical features observed in human MPXV infection. Notably, the animals displayed clinical symptoms and disease progression similar to those of humans, rather than a lethal outcome as observed in previous studies. Historically, MPXV was utilized as a surrogate model for smallpox. However, our study contributes to a better understanding of the dynamics of current MPXV infections while providing a potential infectious NHP model for further evaluation of vaccines and antiviral drugs against mpox infection. Furthermore, the challenge model closely mimics the primary natural routes of transmission for human MPXV infections. This approach enhances our understanding of the precise mechanisms underlying the interhuman transmission of MPXV.

Experimental inoculation of pigs with monkeypox virus results in productive infection and transmission to sentinels

Monkeypox virus (MPXV) is a re-emerging zoonotic poxvirus responsible for producing skin lesions in humans. Endemic in sub-Saharan Africa, the 2022 outbreak with a clade IIb strain has resulted in ongoing sustained transmission of the virus worldwide. MPXV has a relatively wide host range, with infections reported in rodent and non-human primate species. However, the susceptibility of many domestic livestock species remains unknown. Here, we report on a susceptibility/transmission study in domestic pigs that were experimentally inoculated with a 2022 MPXV clade IIb isolate or served as sentinel contact control animals. Several principal-infected and sentinel contact control pigs developed minor lesions near the lips and nose starting at 12 through 18 days post-challenge (DPC). No virus was isolated and no viral DNA was detected from the lesions; however, MPXV antigen was detected by IHC in tissue from a pustule of a principal infected pig. Viral DNA and infectious virus were detected in nasal and oral swabs up to 14 DPC, with peak titers observed at 7 DPC. Viral DNA was also detected in nasal tissues or skin collected from two principal-infected animals at 7 DPC post-mortem. Furthermore, all principal-infected and sentinel control animals enrolled in the study seroconverted. In conclusion, we provide the first evidence that domestic pigs are susceptible to experimental MPXV infection and can transmit the virus to contact animals.

Mpox Virus and its Ocular Surface Manifestations

The Mpox virus (MPXV) is the causative agent of human Mpox disease - a debilitating rash illness similar to smallpox. Although Clade I MPXV has remained endemic to West and Central Africa, Clade II MPXV has been responsible for many outbreaks worldwide. The most recent outbreak in 2022 resulted from the rapid spread of a new clade of MPXV, classified into Clade IIb - a distinct lineage from the previously circulating viral strains. The rapid spread and increased severity of Mpox disease by the Clade IIb strain have raised the serious public health imperative of better understanding the host and viral determinants during MPXV infection. In addition to typical skin rashes, including in the periorbital area, MPXV causes moderate to severe ophthalmic manifestations - most commonly, ocular surface complications (e.g., keratitis, conjunctivitis, blepharitis). While ocular manifestations of Clade I Mpox within the Congo basin have been well-reported, global incidence trends of ocular Mpox cases by Clade IIb are still emerging. Given the demonstrated ability of all MPXV strains to auto-inoculate ocular tissue alongside the enhanced transmissibility of the Clade IIb virus, there is an urgent need to elucidate the mechanisms by which MPXV causes ocular anomalies. In this review, we discuss the viral and genomic structures of MPXV, the epidemiology, and pathology of systemic and ocular Mpox, as well as potential prophylactic and therapeutic interventions.

Effectiveness and Safety of the MVA-BN Vaccine against Mpox in At-Risk Individuals in the United States (USMVAc)

The mpox 2022 outbreak was declared a public health emergency in July 2022. In August 2022, the MVA-BN vaccine received emergency use authorization in the United States (US) to target at-risk groups. This study (EUPAS104386) used HealthVerity's administrative US healthcare data to generate real-world evidence for MVA-BN vaccine effectiveness and safety to prevent mpox disease in men who have sex with men (MSM) and transgender women, the most affected population during the 2022 mpox outbreak. Fully vaccinated subjects (two doses ≥ 28 days apart) were initially matched with five unvaccinated subjects on calendar date, age, US region, and insurance type. Subjects were followed from index date (14 days after the second dose) until death or data end to ascertain mpox occurrence. After propensity score adjustment, the MVA-BN vaccine effectiveness against mpox disease was 89% (95% CI: 12%, 99%) among those fully vaccinated; attenuated to 64% (95% CI: 40%, 78%) among those with any dose and 70% (95% CI: 44%, 84%) for those with only a single dose. One pericarditis adverse event of special interest was observed when the risk window was extended to 28 days. These results contribute to the totality of evidence supporting the favorable benefit/risk profile of the MVA-BN vaccine.

Validation of a new extraction-free real-time PCR test to detect MPOX virus

The monkeypox (Mpox) virus has raised significant concerns given its recent spread with an increasing number of confirmed cases worldwide. In this study, we evaluated the performance of a laboratory developed test (LDT) using BioGX Xfree hMPXV/OPXV reagents for the qualitative detection of non-variola Orthopoxviruses and Mpox virus DNA, in swabs from human pustular or vesicular rash specimens. Analytical and clinical testing analysis were carried out on two different platforms: the BD MAX™ System (BD Diagnostics) and the new pixl.16 Real-Time PCR Platform (BioGX), using a synthetic Mpox virus DNA (ATCC VR-3270SD) and residual clinical samples previously identified with an EUA approved Mpox real-time PCR assay. In the end, the Xfree hMPXV/OPXV LDT proved to be a sensitive, specific, and reproducible test for the detection of Mpox on both platforms evaluated with the pixl.16 having an advantage of a small footprint and providing faster TAT facilitated by an extraction-free workflow.

A global systematic evidence review with meta-analysis of the epidemiological characteristics of the 2022 Mpox outbreaks

BACKGROUND

In 2022, there were outbreaks of Mpox where the disease is not endemic. We summarized published full-text epidemiological data from the outbreaks.

METHODS

A global evidence review (protocol: osf.io/j3kb7) with systematic literature search up to February 09, 2023. We focused on experimental/observational studies of laboratory confirmed Mpox, excluding case reports and case series of < 5 cases. Epidemiological data were pooled using an inverse variance, random-effects model, and pooled estimates presented with associated 95% confidence intervals.

RESULTS

We included 66 studies. Mean incubation period was 7.8 days (6.6-9.0 days, 8 studies: 560 cases), reproductive number 1.8 (1.7-1.9, 6 studies), mean duration from symptom onset to diagnosis 5.8 days (4.8-6.8 days, 4 studies: 982 cases), mean symptom duration 17.5 days (14.7-20.2 days, 3 studies: 292 cases), mean serial interval 8.5 days (7.3-9.9 days, 1 study), hospitalisation 6% (4-9%, 26 studies: 5339 cases), and vaccine effectiveness 78% (65-91%, 3 studies: 953 cases). Highly relevant clinical manifestations were pleomorphic skin lesions 82% (68-94%, 26 studies: 4093 cases), anogenital lesions 64% (51-77%, 9 studies: 10,398 cases), fever 54% (50-57%, 52 studies: 25,992 cases), and lymphadenopathy 51% (46-57%, 42 studies: 17,803 cases), with cases mostly men who have sex with men (MSM). Possibly relevant manifestations were perianal lesions, fatigue, asthenia, myalgia, and headache.

CONCLUSIONS

The 2022 Mpox outbreaks presented with sex-related clinical manifestations and were mostly reported among MSM.

Understanding the biology of monkeypox virus to prevent future outbreaks

Historically, monkeypox (mpox) was a zoonotic disease endemic in Africa. However, in 2022, a global outbreak occurred following a substantial increase in cases in Africa, coupled with spread by international travellers to other continents. Between January 2022 and October 2023, about 91,000 confirmed cases from 115 countries were reported, leading the World Health Organization to declare a public health emergency. The basic biology of monkeypox virus (MPXV) can be inferred from other poxviruses, such as vaccinia virus, and confirmed by genome sequencing. Here the biology of MPXV is reviewed, together with a discussion of adaptive changes during MPXV evolution and implications for transmission. Studying MPXV biology is important to inform specific host interactions, to aid in ongoing outbreaks and to predict those in the future.

Third-generation smallpox vaccines induce low-level cross-protecting neutralizing antibodies against Monkeypox virus in laboratory workers

Due to the discontinuation of routine smallpox vaccination after its eradication in 1980, a large part of the human population remains naïve against smallpox and other members of the orthopoxvirus genus. As a part of biosafety personnel protection programs, laboratory workers receive prophylactic vaccinations against diverse infectious agents, including smallpox. Here, we studied the levels of cross-protecting neutralizing antibodies as well as total IgG induced by either first- or third-generation smallpox vaccines against Monkeypox virus, using a clinical isolate from the 2022 outbreak. Serum neutralization tests indicated better overall neutralization capacity after vaccination with first-generation smallpox vaccines, compared to an attenuated third-generation vaccine. Results obtained from total IgG ELISA, however, did not show higher induction of orthopoxvirus-specific IgGs in first-generation vaccine recipients. Taken together, our results indicate a lower level of cross-protecting neutralizing antibodies against Monkeypox virus in recipients of third-generation smallpox vaccine compared to first-generation vaccine recipients, although total IgG levels were comparable.

Scars are frequently found as late sequelae in individuals affected by the 2022 mpox outbreak

BACKGROUND

The 2022 mpox outbreak continues, and while progress has been made in prevention strategies and potential treatment options, data on late sequelae following mpox are scarce.

OBJECTIVE

This analysis aimed to assess the incidence of scar formation in individuals affected by the 2022 mpox outbreak.

METHODS

All individuals diagnosed with mpox at the Department of Dermatology at the Medical University of Vienna in 2022 were included in this analysis. Follow-up data were collected throughout November 2023. 'Scar formation' was defined as having at least one scar at the former active mpox lesions.

RESULTS

At our clinic, 28 cases of mpox presented between June 2022 and October 2022 and exclusively occurred in men who have sex with men (100%, 28/28), of whom 46% (13/28) were living with HIV, and 32% (9/28) were using pre-exposure prophylaxis (PrEP). Secondary bacterial infection of mpox lesions was suspected in six individuals, and all received systemic antibiotics. Overall, 26 were followed up in November 2023 after a median time of 15 months, and scar formations were found in 43% of cases.

CONCLUSIONS

Our data provide insights into the late yet cumulating disease burden caused by the 2022 mpox outbreak. Highly effective prevention strategies are warranted to overcome the mpox epidemic and its potential late sequelae.

Mpox (Monkeypox) Virus and Its Co-Infection with HIV, Sexually Transmitted Infections, or Bacterial Superinfections: Double Whammy or a New Prime Culprit?

Epidemiologic studies have established that mpox (formerly known as monkeypox) outbreaks worldwide in 2022-2023, due to Clade IIb mpox virus (MPXV), disproportionately affected gay, bisexual, and other men who have sex with men. More than 35% and 40% of the mpox cases suffer from co-infection with HIV and sexually transmitted infections (STIs) (e.g., Chlamydia trachomatis, Neisseria gonorrhoeae, Treponema pallidum, and herpes simplex virus), respectively. Bacterial superinfection can also occur. Co-infection of MPXV and other infectious agents may enhance disease severity, deteriorate outcomes, elongate the recovery process, and potentially contribute to the morbidity and mortality of the ensuing diseases. However, the interplays between MPXV and HIV, bacteria, other STI pathogens and host cells are poorly studied. There are many open questions regarding the impact of co-infections with HIV, STIs, or bacterial superinfections on the diagnosis and treatment of MPXV infections, including clinical and laboratory-confirmed mpox diagnosis, suboptimal treatment effectiveness, and induction of antiviral drug resistance. In this review article, we will discuss the progress and knowledge gaps in MPXV biology, antiviral therapy, pathogenesis of human MPXV and its co-infection with HIV, STIs, or bacterial superinfections, and the impact of the co-infections on the diagnosis and treatment of mpox disease. This review not only sheds light on the MPXV infection and co-infection of other etiologies but also calls for more research on MPXV life cycles and the molecular mechanisms of pathogenesis of co-infection of MPXV and other infectious agents, as well as research and development of a novel multiplex molecular testing panel for the detection of MPXV and other STI co-infections.

Rapid detection of monkeypox virus and differentiation of West African and Congo Basin strains using endonuclease restriction-mediated real-time PCR-based testing

The ongoing multi-country outbreak of monkeypox virus (MPXV) has continuously attracted global attention, highlighting the critical need for timely and accurate methods to detect MPXV and differentiate its clades. Herein, we devised a novel multiplex ET-PCR (endonuclease restriction-mediated real-time PCR) assay that integrates PCR amplification, restriction endonuclease cleavage and real-time fluorescence detection to diagnose MPXV infection and distinguish the Congo Basin and West African MPXV strains. In the MPXV ET-PCR system, three sets of specific primers were designed for MPXV, Congo Basin and West African strains. A short sequence, which could be recognized by restriction endonuclease enzyme BstUI, was added to the 5'end of amplification primers. Then, the modified primers were assigned different reporter dyes and corresponding quenching dyes to each of the three targets, enabling real-time fluorescence reporting of the results and multiplex detection. The designed assay enabled the detection of single or three targets in a single tube, with excellent specificity and analytical sensitivity in terms of plasmid and pseudotyped virus. Moreover, the clinical feasibility of our assay was validated using artificially simulated plasma, nasopharyngeal swab and skin swab samples. In conclusion, the multiplex ET-PCR assay devised here had the advantages of simple primer design, cost-effectiveness, low contamination risk, excellent sensitivity, high specificity and multiplex detection, making it a valuable and dependable tool for curbing the extensive spread of MPXV.

Reverse Zoonotic Transmission of SARS-CoV-2 and Monkeypox Virus: A Comprehensive Review

Reverse zoonosis reveals the process of transmission of a pathogen through the human-animal interface and the spillback of the zoonotic pathogen. In this article, we methodically demonstrate various aspects of reverse zoonosis, with a comprehensive discussion of SARS-CoV-2 and MPXV reverse zoonosis. First, different components of reverse zoonosis, such as humans, different pathogens, and numerous animals (poultry, livestock, pets, wild animals, and zoo animals), have been demonstrated. Second, it explains the present status of reverse zoonosis with different pathogens during previous occurrences of various outbreaks, epidemics, and pandemics. Here, we present 25 examples from literature. Third, using several examples, we comprehensively illustrate the present status of the reverse zoonosis of SARS-CoV-2 and MPXV. Here, we have provided 17 examples of SARS-CoV-2 reverse zoonosis and two examples of MPXV reverse zoonosis. Fourth, we have described two significant aspects of reverse zoonosis: understanding the fundamental aspects of spillback and awareness. These two aspects are required to prevent reverse zoonosis from the current infection with two significant viruses. Finally, the One Health approach was discussed vividly, where we urge scientists from different areas to work collaboratively to solve the issue of reverse zoonosis.

Infection with mpox virus via the genital mucosae increases shedding and transmission in the multimammate rat (Mastomys natalensis)

The 2022 mpox virus (MPXV) outbreak was sustained by human-to-human transmission; however, it is currently unclear which factors lead to sustained transmission of MPXV. Here we present Mastomys natalensis as a model for MPXV transmission after intraperitoneal, rectal, vaginal, aerosol and transdermal inoculation with an early 2022 human outbreak isolate (Clade IIb). Virus shedding and tissue replication were route dependent and occurred in the presence of self-resolving localized skin, lung, reproductive tract or rectal lesions. Mucosal inoculation via the rectal, vaginal and aerosol routes led to increased shedding, replication and a pro-inflammatory T cell profile compared with skin inoculation. Contact transmission was higher from rectally inoculated animals. This suggests that transmission might be sustained by increased susceptibility of the anal and genital mucosae for infection and subsequent virus release.

Characteristics and Differences in Mpox Patients with and without HIV Infection: A Retrospective Cross-Sectional Study in Chengdu, China

Purpose

To date, there are few reports about mpox case series in China, and scarce information is available about the in-vivo kinetics of T-cell responses in the early stage of mpox infection. This study aims to investigate the clinical difference among mpox patients with and without human immunodeficiency virus (HIV) infection.

Patients and Methods

A total of 56 patients diagnosed with mpox by Chengdu Center for Disease Control and Prevention (CDC) and hospitalized in Public Health Clinical Center of Chengdu were retrospectively included and divided into an HIV-infected group (n=23) and a non-HIV-infected group (n=33). Clinical characteristics and serum chemistry findings of mpox patients were collected in order to analyze the differences between the HIV-infected group and the non-HIV-infected group.

Results

Multiple laboratory abnormalities, including elevated C-reactive protein (69.1%), hypocalcemia (50.9%), elevated CD3+CD8+T counts (47.0%) and inverted ratio of CD3+CD4+T to CD3+CD8+T (64.7%) were common in mpox cases. There were statistically significant differences (all P < 0.05) in age, serum calcium levels, CD3+CD4+T counts, the ratio of CD3+CD4+T to CD3+CD8+T, proportion with >10 rashes, incidence of proctitis anus and time from rash growth to rash scab shedding between HIV-infected group and non-HIV-infected group. In the early stage of mpox infection, the median of CD3+CD8+T counts in the non-HIV-infected group was significantly higher than that in healthy donors (P<0.001), and the median of CD3+CD4+T/CD3+CD8+T ratio was significantly lower (P<0.001). The median of CD3+CD4+T counts in mpox patients co-infected with HIV significantly decreased compared to the pre-infection level (p =0.033).

Conclusion

Our study indicates that mpox co-infected with HIV patients have longer lasting rash lesions and a higher incidence of proctitis anus. T-cell responses may be different between HIV-infected and non-HIV-infected individuals in the early stage of mpox infection.

Human monkeypox virus: Epidemiologic review and research progress in diagnosis and treatment

Monkeypox virus (MPXV) is responsible for causing a zoonotic disease called monkeypox (mpox), which sporadically infects humans in West and Central Africa. It first infected humans in 1970 and, along with the variola virus, belongs to the genus Orthopoxvirus in the poxvirus family. Since the World Health Organization declared the MPXV outbreak a "Public Health Emergency of International Concern" on July 23, 2022, the number of infected patients has increased dramatically. To control this epidemic and address this previously neglected disease, MPXV needs to be better understood and reevaluated. In this review, we cover recent research on MPXV, including its genomic and pathogenic characteristics, transmission, mutations and mechanisms, clinical characteristics, epidemiology, laboratory diagnosis, and treatment measures, as well as prevention of MPXV infection in light of the 2022 and 2023 global outbreaks. The 2022 MPXV outbreak has been primarily associated with close intimate contact, including sexual activity, with most cases diagnosed among men who have sex with men. The incubation period of MPXV infection usually lasts from 6 to 13 days, and symptoms include fever, muscle pains, headache, swollen lymph nodes, and a characteristic painful rash, including several stages, such as macules, papules, blisters, pustules, scabs, and scab shedding involving the genitals and anus. Polymerase chain reaction (PCR) is usually used to detect MPXV in skin lesion material. Treatment includes supportive care, antivirals, and intravenous vaccinia immune globulin. Smallpox vaccines have been designed with four givens emergency approval for use against MPXV infection.

Multiple introductions of monkeypox virus to Ireland during the international mpox outbreak, May 2022 to October 2023

BackgroundMpox, caused by monkeypox virus (MPXV), was considered a rare zoonotic disease before May 2022, when a global epidemic of cases in non-endemic countries led to the declaration of a Public Health Emergency of International Concern. Cases of mpox in Ireland, a country without previous mpox reports, could reflect extended local transmission or multiple epidemiological introductions.AimTo elucidate the origins and molecular characteristics of MPXV circulating in Ireland between May 2022 and October 2023.MethodsWhole genome sequencing of MPXV from 75% of all Irish mpox cases (182/242) was performed and compared to sequences retrieved from public databases (n = 3,362). Bayesian approaches were used to infer divergence time between sequences from different subclades and evaluate putative importation events from other countries.ResultsOf 242 detected mpox cases, 99% were males (median age: 35 years; range: 15-60). All 182 analysed genomes were assigned to Clade IIb and, presence of 12 distinguishable subclades suggests multiple introductions into Ireland. Estimation of time to divergence of subclades further supports the hypothesis for multiple importation events from numerous countries, indicative of extended and sustained international spread of mpox. Further analysis of sequences revealed that 92% of nucleotide mutations were from cytosine to thymine (or from guanine to adenine), leading to a high number of non-synonymous mutations across subclades; mutations associated with tecovirimat resistance were not observed.ConclusionWe provide insights into the international transmission dynamics supporting multiple introductions of MPXV into Ireland. Such information supported the implementation of evidence-informed public health control measures.

How the Orthodox Features of Orthopoxviruses Led to an Unorthodox Mpox Outbreak: What We've Learned, and What We Still Need to Understand

Orthopoxviruses have repeatedly confounded expectations in terms of the clinical illness they cause and their patterns of spread. Monkeypox virus (MPXV), originally characterized in the late 1950s during outbreaks among captive primates, has been recognized since the 1970s to cause human disease (mpox) in West and Central Africa, where interhuman transmission has largely been associated with nonsexual, close physical contact. In May 2022, a focus of MPXV transmission was detected, spreading among international networks of gay, bisexual, and other men who have sex with men. The outbreak grew in both size and geographic scope, testing the strength of preparedness tools and public health science alike. In this article we consider what was known about mpox before the 2022 outbreak, what we learned about mpox during the outbreak, and what continued research is needed to ensure that the global public health community can detect, and halt further spread of this disease threat.

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).

A comprehensive review of monkeypox virus and mpox characteristics

Monkeypox virus (MPXV) is the etiological agent of monkeypox (mpox), a zoonotic disease. MPXV is endemic in the forested regions of West and Central Africa, but the virus has recently spread globally, causing outbreaks in multiple non-endemic countries. In this paper, we review the characteristics of the virus, including its ecology, genomics, infection biology, and evolution. We estimate by phylogenomic molecular clock that the B.1 lineage responsible for the 2022 mpox outbreaks has been in circulation since 2016. We interrogate the host-virus interactions that modulate the virus infection biology, signal transduction, pathogenesis, and host immune responses. We highlight the changing pathophysiology and epidemiology of MPXV and summarize recent advances in the prevention and treatment of mpox. In addition, this review identifies knowledge gaps with respect to the virus and the disease, suggests future research directions to address the knowledge gaps, and proposes a One Health approach as an effective strategy to prevent current and future epidemics of mpox.

The need for pre-emptive control strategies for mpox in Asia and Oceania

Introduction

The transmission dynamics of the recent mpox outbreak highlights the lack of infrastructure available to rapidly respond to novel STI outbreaks, of which Asia and Oceania remains particularly susceptible. Here, we simulate outbreaks in this setting and propose the use of pre-emptive vaccination within the men who have sex with men (MSM) community before the arrival and establishment of the virus.

Materials and methods

Using data driven heterogeneous sexual contact networks, we simulated outbreaks of mpox in Singapore, Hong Kong, and Sydney. An individual based SEIR compartmental model was used to simulate epidemic trajectories and the impact of different vaccination uptakes was assessed in their ability to avert or suppress outbreaks upon the arrival of mpox within the MSM populations.

Results

The highly dense sexual networks of Singapore and Sydney experience rapid outbreaks, with infection peaks occurring at day 41 and 23 respectively, compared to Hong Kong which occurs at day 77. Across the simulations with no vaccination, 68.2%-89.7% of the MSM community will become infected with mpox across the different cities, over a simulation period of 1 year. By implementing vaccination strategies, the infection rate across the cities can be reduced to as low as 3.1% of the population (range: 3.1%-82.2%) depending on the implementation and uptake of the vaccine. Vaccination is also extremely effective in slowing the start of the epidemic, delaying the epidemic peak by 36-50 days in Hong Kong, or even preventing the outbreak of mpox.

Discussion

With extremely dense and well-connected sexual contact networks, where 65.2%-83.2% of the population are connected to a super-spreader in the different contact networks, pre-emptive or immediate vaccination upon identification of the first case is strongly recommended to help better manage the outbreak of mpox and prevent potential straining of healthcare systems.

Update on Mpox: What the Primary Care Clinician Should Know

Mpox is a viral infection, which primarily caused sporadic outbreaks in West and Central Africa until causing a global epidemic in 2022. The disease has disproportionately affected people with human immunodeficiency virus and men who have sex with men. Transmission is through close physical contact, including sexual contact. Infection presents with a characteristic rash, with frequent anogenital involvement-polymerase chain reaction of skin lesions is diagnostic. Vaccination is available for primary prevention and postexposure prophylaxis. Treatment consists of supportive care, with antiviral medications available via clinical trials and/or for patients with severe disease.

Synthetic modified vaccinia Ankara vaccines confer cross-reactive and protective immunity against mpox virus

BACKGROUND

Although the mpox global health emergency caused by mpox virus (MPXV) clade IIb.1 has ended, mpox cases are still reported due to low vaccination coverage and waning immunity. COH04S1 is a clinically evaluated, multiantigen COVID-19 vaccine candidate built on a fully synthetic platform of the highly attenuated modified vaccinia Ankara (MVA) vector, representing the only FDA-approved smallpox/mpox vaccine JYNNEOS. Given the potential threat of MPXV resurgence and need for vaccine alternatives, we aimed to assess the capacity COH04S1 and its synthetic MVA (sMVA) backbone to confer MPXV-specific immunity.

METHODS

We evaluated orthopoxvirus-specific and MPXV cross-reactive immune responses in samples collected during a Phase 1 clinical trial of COH04S1 and in non-human primates (NHP) vaccinated with COH04S1 or its sMVA backbone. MPXV cross-reactive immune responses in COH04S1-vaccinated healthy adults were compared to responses measured in healthy subjects vaccinated with JYNNEOS. Additionally, we evaluated the protective efficacy of COH04S1 and sMVA against mpox in mpox-susceptible CAST/EiJ mice.

RESULTS

COH04S1-vaccinated individuals develop robust orthopoxvirus-specific humoral and cellular responses, including cross-reactive antibodies to MPXV-specific virion proteins as well as MPXV cross-neutralizing antibodies in 45% of the subjects. In addition, NHP vaccinated with COH04S1 or sMVA show similar MPXV cross-reactive antibody responses. Moreover, MPXV cross-reactive humoral responses elicited by COH04S1 are comparable to those measured in JYNNEOS-vaccinated subjects. Finally, we show that mice vaccinated with COH04S1 or sMVA are protected from lung infection following challenge with MPXV clade IIb.1.

CONCLUSIONS

These results demonstrate the capacity of sMVA vaccines to elicit cross-reactive and protective orthopox-specific immunity against MPXV, suggesting that COH04S1 and sMVA could be developed as bivalent or monovalent mpox vaccine alternatives against MPXV.

Integrated Network Analysis of Symptom Clusters Across Monkeypox Epidemics From 1970 to 2023: Systematic Review and Meta-Analysis

BACKGROUND

The worldwide spread of monkeypox (mpox) has witnessed a significant increase, particularly in nonendemic countries.

OBJECTIVE

We aimed to investigate the changing clinical symptoms associated with mpox from 1970 to 2023 and explore their interrelations.

METHODS

In this systematic review and meta-analysis, 3 electronic databases were searched for English peer-reviewed studies conducted from January 1970 to April 2023 that reported any symptoms among confirmed mpox cases. We categorized the mpox epidemics into 3 periods: 1970-2002 (period 1, within the African region), 2003-2021(period 2, epidemics outside Africa), and 2022-2023 (period 3, worldwide outbreak). Following PRISMA guidelines, a meta-analysis was performed to estimate the pooled prevalence for each symptom. The correlation among symptoms was analyzed and visualized using network analysis.

RESULTS

The meta-analysis included 61 studies that reported 21 symptoms in 720 patients from period 1, 39 symptoms in 1756 patients from period 2, and 37 symptoms in 12,277 patients from period 3. The most common symptom among patients from all 3 periods was rash (period 1: 92.6%, 95% CI 78.2%-100%; period 2: 100%, 95% CI 99.9%-100%; and period 3: 94.8%, 95% CI 90.9%-98.8%), followed by lymphadenopathy (period 1: 59.8%, 95% CI 50.3%-69.2%; period 2: 74.1%, 95% CI 64.2%-84.1%; and period 3: 61.1%, 95% CI 54.2%-68.1%). Fever (99%, 95% CI 97%-100%), enlarged lymph nodes (80.5%, 95% CI 75.4%-85.0%), and headache (69.1%, 95% CI 4%-100%) were the main symptoms in period 1, with a significant decrease in period 3: 37.9%, 31.2%, and 28.7%, respectively. Chills/rigors (73.3%, 95% CI 60.9%-85.7%), fatigue (68.2%, 95% CI 51.6%-84.8%), and dysphagia/swallowing difficulty (61.2%, 95% CI 10.5%-100%) emerged as primary new symptoms in period 2 and decreased significantly in period 3. Most other symptoms remained unchanged or decreased in period 3 compared to the former 2 periods. Nausea/vomiting had the highest degree of correlation (with 13 symptoms) and was highly positively correlated with lymphadenopathy (r=0.908) and conjunctivitis (r=0.900) in period 2. In contrast, rash and headache were 2 symptoms with the highest degree of correlation (with 21 and 21 symptoms, respectively) in period 3 and were highly positively correlated with fever (r=0.918 and 0.789, respectively).

CONCLUSIONS

The manifestation of symptoms in patients with mpox has become more diverse, leading to an increase in their correlation. Although the prevalence of rash remains steady, other symptoms have decreased. It is necessary to surveil the evolving nature of mpox and the consequential changes in clinical characteristics. Epidemic countries may shift their focus on the potential association among symptoms and the high synergy risk.

TRIAL REGISTRATION

PROSPERO Registration: CRD42023403282; http://tinyurl.com/yruuas5n.

Sensitive and specific CRISPR-Cas12a assisted nanopore with RPA for Monkeypox detection

Monkeypox virus (MPXV) poses a global health emergency, necessitating rapid, simple, and accurate detection to manage its spread effectively. The Clustered Regularly Interspaced Short Palindromic Repeats (CRISPR) technique has emerged as a promising next-generation molecular diagnostic approach. Here, we developed a highly sensitive and specific CRISPR-Cas12a assisted nanopore (SCAN) with isothermal recombinase polymerase amplification (RPA) for MPXV detection. The RPA-SCAN method offers a sensitivity unachievable with unamplified SCAN while also addressing the obstacles of PCR-SCAN for point-of-care applications. We demonstrated that size-counting of single molecules enables analysis of reaction-time dependent distribution of the cleaved reporter. Our MPXV-specific RPA assay achieved a limit of detection (LoD) of 19 copies in a 50 μL reaction system. By integrating 2 μL of RPA amplifications into a 20 μL CRISPR reaction, we attained an overall LoD of 16 copies/μL (26.56 aM) of MPXV at a 95% confidence level using the SCAN sensor. We also verified the specificity of RPA-SCAN in distinguishing MPXV from cowpox virus with 100% accuracy. These findings suggest that the isothermal RPA-SCAN device is well-suited for highly sensitive and specific Monkeypox detection. Given its electronic nature and miniaturization potential, the RPA-SCAN system paves the way for diagnosing a wide array of other infectious pathogens at the point of care.

A Review of Mpox Outbreak and Public Health Response in Spain

Objective

In May 2022, an unprecedented Mpox outbreak was reported in several non-endemic countries with unknown epidemiological links. Since May 2022, more than 20,000 cases have been reported in Europe. Spain has been the most affected country in Europe. We aim to describe the Mpox epidemiological profile in Spain, identify its outbreak risks, and describe public health interventions implemented by the Spanish authorities.

Methods

A literature review was conducted, using specific selection criteria to obtain relevant publications describing Mpox clinical presentation and risk factors and the public health response in Spain to the ongoing outbreak.

Results

63.1% of the cases presented an anogenital rash, considered a specific and early symptom in this outbreak. Low case fatality rate is observed, mainly in risk groups, such as the immunocompromised population. Patients evolution was generally favorable, although 3-8% required hospitalization and two deaths occurred; 40% of patients were previously diagnosed with HIV infection. Most of the cases were seen among young population and concentrated in men who had sex with other men, mainly with multiple sexual partners, who did not practice safe sex such as using condoms, and those attending mass event parties.

Conclusion

To date, the Mpox outbreak is not considered a public health emergency of international concern. The epidemiological trend of the virus in Spain shows that public health response interventions (health education, contact tracing, vaccination, etc.) have adequately controlled the epidemic curve in high-risk populations and avoided spreading the virus to other groups within the community.

Monkeypox Diagnosis in Clinical Settings: A Comprehensive Review of Best Laboratory Practices

An outbreak of monkeypox (Mpox) was reported in more than 40 countries in early 2022. Accurate diagnosis of Mpox can be challenging, but history, clinical findings, and laboratory diagnosis can establish the diagnosis. The pre-analytic phase of testing includes collecting, storing, and transporting specimens. It is advised to swab the lesion site with virus transport medium (VTM) containing Dacron or polyester flock swabs from two different sites. Blood, urine, and semen samples may also be used. Timely sampling is necessary to obtain a sufficient amount of virus or antibodies. The analytical phase of infectious disease control involves diagnostic tools to determine the presence of the virus. While polymerase chain reaction (PCR) is the gold standard for detecting Mpox, genome sequencing is for identifying new or modified viruses. As a complement to these methods, isothermal amplification methods have been designed. ELISA assays are also available for the determination of antibodies. Electron microscopy is another effective diagnostic method for tissue identification of the virus. Wastewater fingerprinting provides some of the most effective diagnostic methods for virus identification at the community level. The advantages and disadvantages of these methods are further discussed. Post-analytic phase requires proper interpretation of test results and the preparation of accurate patient reports that include relevant medical history, clinical guidelines, and recommendations for follow-up testing or treatment.

Monkeypox: Past, Present, and Future

Monkeypox (Mpox) is a zoonotic disease caused by a virus (monkeypox virus-MPV) belonging to the Poxviridae family. In humans, the disease has an incubation period of 5-21 days and then progresses in two phases, the prodromal phase and the rash phase. The prodromal phase is characterized by non-specific symptoms such as fever, muscle pain, malaise, lymphadenopathy, headache, and chills. Skin lesions appear in the rash phase of the disease. These lesions progress through different stages (macules, papules, vesicles, and pustules). In May 2022, WHO reported an outbreak of human Mpox in several countries which were previously Mpox-free. As per the CDC report of March 01, 2023, a total of 86,231 confirmed cases of Mpox and 105 deaths have been reported from 110 countries and territories across the globe. Notably, more than 90% of these countries were reporting Mpox for the first time. The phylogenetic analysis revealed that this outbreak was associated with the virus from the West African clade. However, most of the cases in this outbreak had no evidence of travel histories to MPV-endemic countries in Central or West Africa. This outbreak was primarily driven by the transmission of the virus via intimate contact in men who have sex with men (MSM). The changing epidemiology of Mpox raised concerns about the increasing spread of the disease in non-endemic countries and the urgent need to control and prevent it. In this chapter, we present all the documented cases of Mpox from 1970 to 2023 and discuss the past, present, and future of MPV.

Poxviridae Pneumonia

Poxviridae family includes several viruses that infecting humans usually causes skin lesions only, but in some cases their clinical course is complicated by viral pneumonia (with or without bacterial superinfections). Historically variola virus has been the poxviridae most frequently associated with the development of pneumonia with many large outbreaks worldwide before its eradication in 1980. It is still considered a biological threat for its potential in biological warfare and bioterrorism. Smallpox pneumonia can be severe with the onset of acute respiratory distress syndrome (ARDS) and death. Vaccinia virus, used for vaccination against smallpox exceptionally, in immunocompromised patients, can induce generalized (with also lung involvement) severe disease after vaccination. MPXV virus occasionally can cause pneumonia particularly in immunocompromised patients. The pathophysiology of poxviridae pneumonia is still an area of active research; however, in animal models these viruses can cause both direct damage to the lower airways epithelium and a hyperinflammatory syndrome, like a cytokine storm. Multiple mechanisms of immune evasion have also been described. The treatment of poxviridae pneumonia is mainly based on careful supportive care. Despite the absence of randomized clinical trials in patients with poxviridae pneumonia there are antiviral drugs, such as tecovirimat, cidofovir and brincidofovir, FDA-approved for use in smallpox and also available under an expanded access protocol for treatment of MPXV. There are 2 (replication-deficient modified vaccinia Ankara and replication-competent vaccinia virus) smallpox vaccines FDA-approved with the first one also approved for prevention of MPXV in adults that are at high risk of infection.

The 2022 monkeypox outbreak 1 year on: The 5 Ws

In May 2022, World Health Organization (WHO) reported an outbreak of Mpox in several European countries which were previously Mpox free. Mpox (formerly known as monkeypox) is a zoonotic viral disease endemic in Central and West Africa. The sudden emergence of Mpox outside Africa and its subsequent rapid spread lead the WHO to declare the outbreak as Public Health Emergency of International Concern. By 15 May 2023, a total of 87,704 confirmed cases and 140 deaths had been reported from 111 countries and territories worldwide. Looking back on this outbreak 1 year later, several important questions have arisen. Here, we address these questions using the classic 5 Ws: What, When, Where, Who and Why? We discuss these questions to understand how this outbreak emerged and how it was effectively managed. We outline what needs to be done to prevent, or at least minimise, outbreaks due to emerging and re-emerging viral infections.

Environmental detection and spreading of mpox in healthcare settings: a narrative review

Monkeypox virus (MPXV), which causes Monkeypox (Mpox), has recently been found outside its usual geographic distribution and has spread to 117 different nations. The World Health Organization (WHO) designated the epidemic a Public Health Emergency of International Concern (PHEIC). Humans are at risk from MPXV's spread, which has raised concerns, particularly in the wake of the SARS-CoV-2 epidemic. The risk of virus transmission may rise due to the persistence of MPXV on surfaces or in wastewater. The risk of infection may also increase due to insufficient wastewater treatment allowing the virus to survive in the environment. To manage the infection cycle, it is essential to investigate the viral shedding from various lesions, the persistence of MPXV on multiple surfaces, and the length of surface contamination. Environmental contamination may contribute to virus persistence and future infection transmission. The best possible infection control and disinfection techniques depend on this knowledge. It is thought to spread mainly through intimate contact. However, the idea of virus transmission by environmental contamination creates great concern and discussion. There are more cases of environmental surfaces and wastewater contamination. We will talk about wastewater contamination, methods of disinfection, and the present wastewater treatment in this review as well as the persistence of MPXV on various environmental surfaces.

Monitoring of monkeypox viral DNA in Prague wastewater

Monkeypox virus (Mpxv) is a dsDNA virus that has become a global concern for human health in 2022. As both infected people and non-human hosts can shed the virus from their skin, faeces, urine and other body fluids, and the resulting sewage contains viral load representative of the whole population, it is highly promising to detect the spread of monkeypox virus in municipal wastewater. We established a methodology for sewage-based monitoring of Mpxv in Prague and analysed samples (n = 24) already early August-October of 2022 in a municipality with 1.4 million inhabitants that only reported 29 cumulative cases in this period. We isolated Mpxv DNA with the Wizard Enviro Total Nucleic Acid Kit, and thereafter detected Mpxv DNA using the EliGene® Monkeypox RT-PCR Kit. Prague wastewater was positive for Mpxv (in total 9 positive samples in periods with 1-9 new cases per week, coinciding with a weekly incidence of 0.07-0.64 per 100,000 inhabitants. The method for confirmation of wastewater positivity via semi-nested PCR and Sanger sequencing was successfully confirmed on positive controls including Mpxv particles and Mpxv-positive wastewater from the Netherlands. However, for Prague wastewater samples, amplification of Mpxv DNA via semi-semi-nested PCR was unsuccessful. This was probably due to extremely low case count, leading to the amplification of non-target bacterial DNA. Compared to other studies with much higher Mpxv prevalence, we show the outstanding sensitivity of our approach for monitoring the spread of monkeypox using wastewater.

Monkeypox Virus Immune Evasion and Eye Manifestation: Beyond Eyelid Implications

Monkeypox virus (MPXV), belonging to the Poxviridae family and Orthopoxvirus genus, is closely related to the smallpox virus. Initial prodromal symptoms typically include headache, fever, and lymphadenopathy. This review aims to detail various ocular manifestations and immune evasion associated with the monkeypox viral infection and its complications, making it appropriate as a narrative review. Common external ocular manifestations of MPXV typically involve a generalized pustular rash, keratitis, discharges, and dried secretions related to conjunctival pustules, photophobia, and lacrimation. Orthopoxviruses can evade host immune responses by secreting proteins that antagonize the functions of host IFNγ, CC and CXC chemokines, IL-1β, and the complement system. One of the most important transcription factors downstream of pattern recognition receptors binding is IRF3, which controls the expression of the crucial antiviral molecules IFNα and IFNβ. We strongly recommend that ophthalmologists include MPXV as part of their differential diagnosis when they encounter similar cases presenting with ophthalmic manifestations such as conjunctivitis, blepharitis, or corneal lesions. Furthermore, because non-vaccinated individuals are more likely to exhibit these symptoms, it is recommended that healthcare administrators prioritize smallpox vaccination for at-risk groups, including very young children, pregnant women, older adults, and immunocompromised individuals, especially those in close contact with MPXV cases.

Efficacy of smallpox vaccines against Mpox infections in humans

The Mpox virus (MPXV) is endemic in certain countries in Central and West Africa, where several mammalian species, especially rodents, are natural reservoirs. However, the MPXV can infect nonhuman primates and cause zoonotic infections in humans after close contact with an infected animal. Human-to-human transmission of MPXV can also occur through direct close contact with an infected individual or infected materials. In May 2022 an initial cluster of human Mpox cases was identified in the UK, with the first case confirmed in a patient who had recently travelled to Nigeria. The infection subsequently spread via human-to-human transmission within the UK and Mpox cases began to appear in many other countries around the world where the MPXV is not endemic. No specific treatments for MPXV infection in humans are available. However, data from studies undertaken in Zaire in the 1980s revealed that those with a history of smallpox vaccination during the global smallpox eradication campaign also had good cross-protection against MPXV infection. However, the vaccines used during the global eradication campaign are no longer available. During the 2022 global Mpox outbreak over a million doses of the Modified Vaccinia Ankara-Bavarian Nordic (MVA-BN) smallpox vaccine were offered either as pre or postexposure prophylaxis to those at high risk of MPXV infection. Here, we review what has been learned about the efficacy of smallpox vaccines in reducing the incidence of MPXV infections in high-risk close contacts.

Entropy-Driven, Integrative Bioinformatics Approaches Reveal the Recent Transmission of the Monkeypox Virus from Nigeria to Multiple Non-African Countries

Monkeypox virus (mpox) has currently affected multiple countries around the globe. This study aims to analyze how the virus spread globally. The study uses entropy-driven bioinformatics in five directions to analyze the 60 full-length complete genomes of mpox. We analyzed the topological entropy distribution of the genomes, principal component analysis (PCA), the dissimilarity matrix, entropy-driven phylogenetics, and genome clustering. The topological entropy distribution showed genome positional entropy. We found five clusters of the mpox genomes through the two PCA, while the three PCA elucidated the clustering events in 3D space. The clustering of genomes was further confirmed through the dissimilarity matrix and phylogenetic analysis which showed the bigger size of Cluster 1 and size similarity between Clusters 2 and 4 as well as Clusters 3 and 5. It corroborated with the phylogenetics of the genomes, where Cluster 1 showed clear segregation from the other four clusters. Finally, the study concluded that the spreading of the mpox is likely to have originated from African countries to the rest of the non-African countries. Overall, the spreading and distribution of the mpox will shed light on its evolution and pathogenicity of the mpox and help to adopt preventive measures to stop the spreading of the virus.

The Human Mpox Global Outbreak: Available Control Tools and the Opportunity to Break a Cycle of Neglect in Endemic Countries

The 2022 global outbreak of human Mpox (formerly monkeypox) virus (MPXV) infection outside of the usual endemic zones in Africa challenged our understanding of the virus's natural history, transmission dynamics, and risk factors. This outbreak has highlighted the need for diagnostics, vaccines, therapeutics, and implementation research, all of which require more substantial investments in equitable collaborative partnerships. Global multidisciplinary networks need to tackle MPXV and other neglected emerging and reemerging zoonotic pathogens to address them locally and prevent or quickly control their worldwide spread. Political endorsement from individual countries and financial commitments to maintain control efforts will be essential for long-term sustainability.

Mpox virus and coinfections: An approach to rapid diagnosis

We report a case of a 42-year-old immunocompromised (human immunodeficiency virus [HIV], CD4 count 86 cells/μL) Black male who presented with fever, oropharyngeal candidiasis, and phimosis, followed by eruption of umbilicated papulovesicles most concentrated on the face. The patient was diagnosed with Mpox (MPXV, formerly monkeypox), herpes simplex virus 1 (HSV1), varicella-zoster virus (VZV), and late latent syphilis. Tzanck smear of a Mpox lesion proved a useful and rapidly obtained pertinent negative test, lacking the typical changes of HSV/VZV (multinucleation, margination, and molding). A biopsy specimen showed viral changes consistent with both Mpox (ballooning degeneration and multinucleated keratinocytes) and herpesvirus (multinucleated epithelial giant cell within a zone of follicular necrosis). Lesion PCR was positive for HSV1 and MPXV, and negative for HSV2 and VZV. Immunohistochemistry was positive for VZV and orthopoxvirus. Empiric treatment for HSV/VZV in patients with suspected or confirmed Mpox should be considered for patients with HIV or other immunocompromised patients. It is important to recognize that MPXV, HSV, and VZV may all be present and difficult to distinguish clinically. More than one test modality (PCR, H&E, immunohistochemistry, and Tzanck) and multiple lesion samples may be required to thoroughly evaluate widespread papulovesicular eruptions, especially in immunocompromised patients.

Differences in pathogenicity among the mpox virus clades: impact on drug discovery and vaccine development

Since May 2022, mpox virus (MPXV) has attracted considerable attention due to a multi-country outbreak. Marked differences in epidemiology, transmission, and pathology between the 2022 global mpox outbreak (clade IIb) and classical mpox disease, endemic in Africa (clades I and IIa) have been highlighted. MPXV genome analysis has identified the genomic changes characterizing clade IIb and the drivers of MPXV rapid evolution. Although mpox cases have largely declined, MPXV cryptic transmission and microevolution continues, which may lead to an MPXV of unpredictable pathogenicity. Vaccines and antivirals developed against variola virus, the agent that caused the extinguished plague smallpox, have been used to contain the 2022 mpox outbreak. In this review article, recent findings on MPXV origin and evolution and relevant models able to recapitulate differences in MPXV pathogenicity, which are important for drug and vaccine development, are discussed.

Generation of recombinant mAbs to vaccinia virus displaying high affinity and potent neutralization

Members of the Orthopoxvirus genus can cause severe infections in humans. Global vaccination against smallpox, caused by the variola virus, resulted in the eradication of the disease in 1980. Shortly thereafter, vaccination was discontinued, and as a result, a large proportion of the current population is not protected against orthopoxviruses. The concerns that the variola virus or other engineered forms of poxviruses may re-emerge as bioweapons and the sporadic outbreaks of zoonotic members of the family, such as Mpox, which are becoming more frequent and prevalent, also emphasize the need for an effective treatment against orthopoxviruses. To date, the most effective way to prevent or control an orthopoxvirus outbreak is through vaccination. However, the traditional vaccinia-based vaccine may cause severe side effects. Vaccinia immune globulin was approved by the U.S. Food and Drug Administration (FDA) for the treatment of vaccine adverse reactions and was also used occasionally for the treatment of severe orthopoxvirus infections. However, this treatment carries many disadvantages and is also in short supply. Thus, a recombinant alternative is highly needed. In this study, two non-human primates were immunized with live vaccinia virus, producing a robust and diverse antibody response. A phage-display library was constructed based on the animal's lymphatic organs, and a panel of neutralizing monoclonal antibodies (mAbs), recognizing diverse proteins of the vaccinia virus, was selected and characterized. These antibodies recognized both mature virion and enveloped virion forms of the virus and exhibited high affinity and potent in vitro neutralization capabilities. Furthermore, these monoclonal antibodies were able to neutralize Mpox 2018 and 2022 strains, suggesting a potential for cross-species protection. We suggest that a combination of these mAbs has the potential to serve as recombinant therapy both for vaccinia vaccine adverse reactions and for orthopoxvirus infections. IMPORTANCE In this manuscript, we report the isolation and characterization of several recombinant neutralizing monoclonal antibodies (mAbs) identified by screening a phage-display library constructed from lymphatic cells collected from immunized non-human primates. The antibodies target several different antigens of the vaccinia virus, covering both mature virion and extracellular enveloped virion forms of the virus. We document strong evidence indicating that they exhibit excellent affinity to their respective antigens and, most importantly, optimal in vitro neutralization of the virus, which exceeded that of vaccinia immune globulin. Furthermore, we present the ability of these novel isolated mAbs (as well as the sera collected from vaccinia-immunized animals) to neutralize two Mpox strains from the 2018 to 2022 outbreaks. We believe that these antibodies have the potential to be used for the treatment of vaccinia vaccine adverse reactions, for other orthopoxvirus infections, and in cases of unexpected bioterror scenarios.

Non-adaptive evolution in codon usage of human-origin monkeypox virus

Monkeypox virus (Mpox) is a zoonotic infectious disease that threatens human and animal health, with a global outbreak of the low-pathogenic Mpox beginning from 2022. In this study, we analyzed the codon usage of Mpox between two clades, Clade-I and Clade-IIb-B, to understand changes in host adaptation. Clade-IIb-B of the Mpox genome underwent non-adaptive evolution making it less adapted to its host than Clade-I. The analysis of individual genes revealed that 48 genes exhibited non-adaptive mutation, while 38 genes underwent adaptive mutations. Genes involved in replication, transcription, and host-modulation exhibited a mix of adaptive and non-adaptive evolutionary patterns. This study also found that the mutations of Mpox led to changes in non-adaptative genes in different organs. Additionally, we found that codon usage of Mpox was less similar to that of up-regulated host genes and more similar to that of down-regulated host genes post-infection, indicating that codon usage affects host gene expression. Overall, the study highlights the non-adaptive changes in codon usage as a potential cause of differences in Mpox virulence and provides insights into the evolutionary and adaptive mechanisms of Mpox and its potential impact on pathogenicity and host adaptation.

Revisiting VH1 phosphatase at the time of monkeypox: back to the spotlight

Vaccinia virus is a poxvirus that has been successfully leveraged to develop vaccines for smallpox, which is caused by the closely related Variola virus. Smallpox has been declared as 'eradicated' by the WHO in 1980; however, it still poses a potential bioterrorism threat. More recently, the spreading of monkeypox (MPox) in non-endemic countries has further highlighted the importance of continuing the exploration for druggable targets for poxvirus infections. The vaccinia H1 (VH1) phosphatase is the first reported dual specificity phosphatase (DUSP) able to hydrolyze both phosphotyrosine and phosphoserine/phosphotheonine residues. VH1 is a 20 kDa protein that forms a stable dimer and can dephosphorylate both viral and cellular substrates to regulate the viral replication cycle and host immune response. VH1 dimers adopt a domain swap mechanism with the first 20 amino acids of each monomer involved in dense electrostatic interaction and salt bridge formations while hydrophobic interactions between the N-terminal and C-terminal helices further stabilize the dimer. VH1 appears to be an ideal candidate for discovery of novel anti-poxvirus agents because it is highly conserved within the poxviridae family and is a virulence factor, yet it displays significant divergence in sequence and dimerization mechanism from its human closest ortholog vaccinia H1-related (VHR) phosphatase, encoded by the DUSP3 gene. As the dimeric quaternary structure of VH1 is essential for its phosphatase activity, strategies leading to disruption of the dimer structure might aid in VH1 inhibitor development.

Mpox Vaccination in Non-Endemic Countries: Considerations for Public Health and Policy

The disease mpox (formerly monkeypox) is a zoonotic viral disease caused by a virus belonging to the Orthopoxvirus, the same genus as smallpox [...].

Identification of In Vitro Inhibitors of Monkeypox Replication

Monkeypox virus (MPXV) infections in humans have historically been restricted to regions of endemicity in Africa. However, in 2022, an alarming number of MPXV cases were reported globally, with evidence of person-to-person transmission. Because of this, the World Health Organization (WHO) declared the MPXV outbreak a public health emergency of international concern. The supply of MPXV vaccines is limited, and only two antivirals, tecovirimat and brincidofovir, approved by the U.S. Food and Drug Administration (FDA) for the treatment of smallpox, are currently available for the treatment of MPXV infection. Here, we evaluated 19 compounds previously shown to inhibit different RNA viruses for their ability to inhibit orthopoxvirus infections. We first used recombinant vaccinia virus (rVACV) expressing fluorescence (mScarlet or green fluorescent protein [GFP]) and luciferase (Nluc) reporter genes to identify compounds with antiorthopoxvirus activity. Seven compounds from the ReFRAME library (antimycin A, mycophenolic acid, AVN-944, pyrazofurin, mycophenolate mofetil, azaribine, and brequinar) and six compounds from the NPC library (buparvaquone, valinomycin, narasin, monensin, rotenone, and mubritinib) showed inhibitory activity against rVACV. Notably, the anti-VACV activity of some of the compounds in the ReFRAME library (antimycin A, mycophenolic acid, AVN-944, mycophenolate mofetil, and brequinar) and all the compounds from the NPC library (buparvaquone, valinomycin, narasin, monensin, rotenone, and mubritinib) were confirmed with MPXV, demonstrating their inhibitory activity in vitro against two orthopoxviruses. IMPORTANCE Despite the eradication of smallpox, some orthopoxviruses remain important human pathogens, as exemplified by the recent 2022 monkeypox virus (MPXV) outbreak. Although smallpox vaccines are effective against MPXV, access to those vaccines is limited. In addition, current antiviral treatment against MPXV infections is limited to the use of the FDA-approved drugs tecovirimat and brincidofovir. Thus, there is an urgent need to identify novel antivirals for the treatment of MPXV infection and other potentially zoonotic orthopoxvirus infections. Here, we show that 13 compounds, derived from two different libraries, previously found to inhibit several RNA viruses, also inhibit VACV. Notably, 11 compounds also displayed inhibitory activity against MPXV.

Implementation and clinical evaluation of an Mpox virus laboratory-developed test on a fully automated random-access platform

While Mpox virus (MPXV) diagnostics were performed in specialized laboratories only, the global emergence of Mpox cases in 2022 revealed the need for a more readily available diagnostic. Automated random-access platforms with fast nucleic acid extraction and PCR have become established in many laboratories, providing faster and more accessible testing. In this study, we adapted a previously published generic MPXV-PCR as a lab-developed test (LDT) on a NeuMoDx Molecular System and isolated MPXV clones from patient materials. To reduce the handling of infectious material, we evaluated a viral lysis buffer (VLB) for sample pretreatment. We further compared the MPXV-LDT-PCR to conventional real-time PCR, determined its sensitivity and specificity using positive swabs, and assessed its performance using external quality assessment samples. Pretreatment of samples with 50% VLB reduced MPXV infectivity by approximately 200-fold while maintaining PCR sensitivity. The assay demonstrated a sensitivity and specificity of 100% with no cross-reactivity in the samples tested and performed with a limit of detection of 262 GE/mL. In summary, the assay had a turnaround time of fewer than 2 h and can easily be transferred to other automated PCR platforms, providing a basis for developing rapid assays for upcoming pandemics.

Intra- and interhost genomic diversity of monkeypox virus

The impact and frequency of infectious disease outbreaks demonstrate the need for timely genomic surveillance to inform public health responses. In the largest known outbreak of mpox, genomic surveillance efforts have primarily focused on high-incidence nations in Europe and the Americas, with a paucity of data from South-East Asia and the Western Pacific. Here we analyzed 102 monkeypox virus (MPXV) genomes sampled from 56 individuals in Melbourne, Australia. All genomes fell within the 2022 MPXV outbreak lineage (B.1), with likely onward local transmission detected. We observed within-host diversity and instances of co-infection, and highlight further examples of structural variation and apolipoprotein B editing complex-driven micro-evolution in the current MPXV outbreak. Updating our understanding of MPXV emergence and diversification will inform public health measures and enable monitoring of the virus' evolutionary trajectory throughout the mpox outbreak.

Emerging pharmacological strategies for treating and preventing mpox

INTRODUCTION

Since May 2022, there have been nearly 87,000 documented cases of mpox worldwide, with 119 deaths. Pharmacological interventions for mpox include the MVA-BN smallpox vaccine, tecovirimat, cidofovir, its pro-drug brincidofovir, and vaccinia immune globulin intravenous (VIGIV).

AREAS COVERED

The literature search and information gathering for this review included the PubMed database focusing on mpox and monkeypox, in combination with tecovirimat, brincidofovir, cidofovir, VIGIV, and smallpox vaccine. WHO.int, CDC.gov, FDA.gov, and ClinicalTrials.gov websites were accessed for the most recent information on the mpox outbreak. Mechanisms for deployment and access to treatment including expanded access, emergency use, and clinical trials will be discussed. Treatment outcomes with safety data will be presented.

EXPERT OPINION

The vaccine as a preventive measure, along with numerous treatment options, largely controlled the outbreak, although deployment of each could be improved upon to hasten and broaden access. More widespread coverage by the vaccine is necessary to prevent future resurgence of mpox. Tecovirimat has emerged as a safe frontline treatment for mpox, while brincidofovir use has been limited by safety concerns. VIGIV and cidofovir should be reserved for the most severe cases in which other options are not fully effective.

Sequencing of monkeypox virus from infected patients reveals viral genomes with APOBEC3-like editing, gene inactivation, and bacterial agents of skin superinfection

A large outbreak of Monkeypox virus (MPXV) infections has arisen in May 2022 in nonendemic countries. Here, we performed DNA metagenomics using next-generation sequencing with Illumina or Nanopore technologies for clinical samples from MPXV-infected patients diagnosed between June and July 2022. Classification of the MPXV genomes and determination of their mutational patterns were performed using Nextclade. Twenty-five samples from 25 patients were studied. A MPXV genome was obtained for 18 patients, essentially from skin lesions and rectal swabbing. All 18 genomes were classified in clade IIb, lineage B.1, and we identified four B.1 sublineages (B.1.1, B.1.10, B.1.12, B.1.14). We detected a high number of mutations (range, 64-73) relatively to a 2018 Nigerian genome (genome GenBank Accession no. NC_063383.1), which were harbored by a large part of a set of 3184 MPXV genomes of lineage B.1 recovered from GenBank and Nextstrain; and we detected 35 mutations relatively to genome ON563414.3 (a B.1 lineage reference genome). Nonsynonymous mutations occurred in genes encoding central proteins, among which transcription factors and core and envelope proteins, and included two mutations that would truncate a RNA polymerase subunit and a phospholipase d-like protein, suggesting an alternative start codon and gene inactivation, respectively. A large majority (94%) of nucleotide substitutions were G > A or C > U, suggesting the action of human APOBEC3 enzymes. Finally, >1000 reads were identified as from Staphylococcus aureus and Streptococcus pyogenes for 3 and 6 samples, respectively. These findings warrant a close genomic monitoring of MPXV to get a better picture of the genetic micro-evolution and mutational patterns of this virus, and a close clinical monitoring of skin bacterial superinfection in monkeypox patients.

Comparative evaluation of the clinical presentation and epidemiology of the 2022 and previous Mpox outbreaks: a rapid review and meta-analysis

BACKGROUND

In 2022, there were outbreaks of Mpox where the disease is not endemic. We summarised and compared the findings from published observational studies on the clinical presentation and epidemiology of the 2022 and previous outbreaks of Mpox.

METHODS

We registered a review protocol with the Open Science Framework (osf.io/j3kb7). We searched MEDLINE, Embase, CENTRAL, CINAHL and Scopus databases, and relevant websites up to August 30, 2022. Retrieved literature citations were screened for eligibility, and summary clinical presentation and epidemiological data from the included studies were pooled, when possible, using an inverse variance, random-effects model.

RESULTS

Seventy-nine studies met the eligibility. Irrespective of outbreak, fever, headache, myalgia, lymphadenopathy, pleomorphic skin lesions, oral lesions, and sore throat were potentially highly relevant Mpox manifestations, while conjunctivitis, cough, and possibly reactivation of varicella zoster virus may be part of the clinical presentation. The mean incubation period for the 2022 outbreaks was 7.4 d (6.4-8.4 d, I² 64.2%; 4 studies: 270 cases) and for previous outbreaks, 12.9 d (10.4-15.5 d; one study: 31 cases), p < .001. None of the male cases from previous outbreaks was reported to have sex with men (MSM) whereas almost all reported male cases from the 2022 outbreak were MSM. Concomitant sexually transmitted infections and perianal lesions were reported only among male cases from the 2022 outbreak, with the cases mostly presenting with genital lesions.

CONCLUSIONS

The 2022 Mpox outbreaks appear to be mostly among MSM and have a lower incubation period compared with previous outbreaks.Key messages79 studies met the review's inclusion criteria.The 2022 Mpox outbreaks appear to have shorter incubation period compared with previous outbreaks.Established clinical presentation of Mpox includes fever, headache, myalgia, lymphadenopathy, pleomorphic skin lesions, oral lesions, and sore throat.Almost all reported cases from the 2022 Mpox outbreaks were men who had sex with men (MSM).Concomitant sexually transmitted infections and perianal lesions were only reported among cases from the 2022 Mpox outbreaks.A significantly higher proportion of Mpox cases from the 2022 outbreaks had genital lesions compared with cases from previous outbreaks.The 2022 Mpox outbreaks appear to be mostly among MSM.

Monkeypox: a global health emergency

Over the past 2 years, the world has faced the impactful Coronavirus Disease-2019 (COVID-19) pandemic, with a visible shift in economy, medicine, and beyond. As of recent times, the emergence of the monkeypox (mpox) virus infections and the growing number of infected cases have raised panic and fear among people, not only due to its resemblance to the now eradicated smallpox virus, but also because another potential pandemic could have catastrophic consequences, globally. However, studies of the smallpox virus performed in the past and wisdom gained from the COVID-19 pandemic are the two most helpful tools for humanity that can prevent major outbreaks of the mpox virus, thus warding off another pandemic. Because smallpox and mpox are part of the same virus genus, the Orthopoxvirus genus, the structure and pathogenesis, as well as the transmission of both these two viruses are highly similar. Because of these similarities, antivirals and vaccines approved and licensed in the past for the smallpox virus are effective and could successfully treat and prevent an mpox virus infection. This review discusses the main components that outline this current global health issue raised by the mpox virus, by presenting it as a whole, and integrating aspects such as its structure, pathogenesis, clinical aspects, prevention, and treatment options, and how this ongoing phenomenon is being globally approached.