Molecular Aspects of the Monkeypox Virus and their Impact on the Virus's Change in Epidemiology.

OBJECTIVE: Monkeypox is a viral zoonotic disease endemic to West and Central Africa; it has been reported in more countries during the last decade than in the previous 40 years. In 2022 a multinational outbreak occurred. This change in the epidemiology of the virus may represent an evolutionary adaptation. The purpose of this study is to analyze the molecular aspects of Monkeypox virus (MPXV) disease that may explain the latter's change in epidemiology during the 2022 outbreak. METHODS: From July 2022 through December 2022, the period of the outbreak, a narrative review was conducted on the available literature, with a total of 271 articles published in the MEDLINE/PubMed and LILACS databases being examined. The chosen articles were organized using the search and reference manager Mendeley Desktop 1.19.4. Duplicates and articles that did not meet the study's objective were eliminated, resulting in the selection of 49 articles for the present review. DISCUSSION: MPXV resurgence poses challenges due to waning immunity and changing epidemiological patterns. Recent outbreaks show different transmission routes, affecting new demographics. Genomic evolution, vaccination history, and potential new animal reservoirs complicate containment efforts. Continued surveillance and vaccination are crucial for control. CONCLUSIONS: It seems possible that MPXV has (re-)emerged to occupy the ecological niche left by the smallpox virus. Mutations of the apolipoprotein B mRNA editing enzyme, catalytic subunit 3G motif, in MPXV clade IIb since 2017 may explain the epidemiological change that has occurred in recent years. This pattern could be due to sustained transmission in a new host or a new route of infection.

Emergence of monkeypox virus in central Argentina: Epidemiological features and first complete genome sequences in the country.

Monkeypox (Mpox) is a zoonotic disease caused by the monkeypox virus (MPXV). MPXV can be transmitted by close contact with lesions, body fluids, respiratory droplets, and contaminated materials. A new pattern of spread among sexual networks has been recently described. The present work aimed to report the epidemiological and genomic characterization of the 2022 MPXV outbreak in central Argentina. A total of 113 scabs and/or lesion swab specimens were studied. MPXV infection was confirmed in 46.0% of the studied patients, all of whom were men. Varicella-zoster virus infection was the most frequent differential diagnosis. Eight complete viral genomes were obtained by next-generation sequencing. The Argentinian sequences were grouped intermingled with other sequences from the 2022 MPXV outbreak, related to samples from the USA, Europe, and Peru. Taken together, our study provided an initial assessment of the genetic and epidemiological characteristics of the 2022 MPXV outbreak in Córdoba, Argentina.

Differential diagnosis of exanthematous viruses during the 2022 Mpox outbreak in Minas Gerais, Brazil.

The monkeypox virus (MPXV) outbreak, primarily endemic to Africa, has spread globally, with Brazil reporting the second-highest number of cases. The emergence of MPXV in non-endemic areas has raised concerns, particularly due to the co-circulation of other exanthematous viruses such as varicella-zoster virus (VZV) and molluscum contagiosum virus (MOCV). To perform an accurate differential diagnosis of MPXV during the ongoing outbreak in Minas Gerais, Brazil, a 5PLEX qPCR assay targeting orthopoxviruses (OPV), VZV, and MOCV was used to retrospectively analyze all clinical samples that tested negative for MPXV in the initial screening conducted at Funed. In summary, our study analyzed 1,175 clinical samples received from patients suspected of MPXV infection and found a positivity rate of 33.8% (397 samples) for MPXV using the non-variola qPCR assay. Testing the 778 MPXV-negative clinical samples using the 5PLEX qPCR assay revealed that 174 clinical samples (22.36%) tested positive for VZV. MOCV DNA was detected in 13 and other OPV in 3 clinical samples. The sequencing of randomly selected amplified clinical samples confirmed the initial molecular diagnosis. Analysis of patient profiles revealed a significant difference in the median age between groups testing positive for MPXV and VZV and a male predominance in MPXV cases. The geographic distribution of positive cases was concentrated in the most populous mesoregions of Minas Gerais state. This study highlights the challenges posed by emerging infectious diseases. It emphasizes the importance of epidemiological surveillance and accurate diagnosis in enabling timely responses for public health policies and appropriate medical care. IMPORTANCE: Brazil ranks second in the number of cases during the global monkeypox epidemic. The study, conducted in Minas Gerais, the second most populous state in Brazil with over 20 million inhabitants, utilized differential diagnostics, revealing a significant number of positive cases for other exanthematous viruses and emphasizing the need for accurate diagnoses. During the study, we were able to assess the co-circulation of other viruses alongside monkeypox, including varicella-zoster virus, molluscum contagiosum virus, and other orthopoxviruses. The significance of the research is underscored by the concentration of positive cases in populous areas, highlighting the challenges posed by emerging infectious diseases. This demographic context further amplifies the importance of the research in guiding public health policies and medical interventions, given the substantial population at risk. The study not only addresses a global concern but also holds critical implications for a state with such a large population and geographic expanse within Brazil. Overall, the study emphasizes the pivotal role of surveillance and precise diagnosis in guiding effective public health responses and ensuring appropriate medical interventions.

Genetic insights into the microevolutionary dynamics and early introductions of human monkeypox virus in Mexico.

The recent global outbreak of mpox, caused by monkeypox virus (MPV) emerged in Europe in 2022 and rapidly spread to over 40 countries. The Americas are currently facing the highest impact, reporting over 50,000 cases by early 2023. In this study, we analyzed 880 MPV isolates worldwide to gain insights into the evolutionary patterns and initial introduction events of the virus in Mexico. We found that MPV entered Mexico on multiple occasions, from the United Kingdom, Portugal, and Canada, and subsequently spread locally in different regions of Mexico. Additionally, we show that MPV has an open pangenome, highlighting the role of gene turnover in shaping its genomic diversity, rather than single-nucleotide polymorphisms (SNPs), which do not contribute significantly to genome diversity. Although the genome contains multiple SNPs in coding regions, these remain under purifying selection, suggesting their evolutionary conservation. One notable exception is amino acid position 63 of the protein encoded by the Cop-A4L gene, which is intricately related to viral maturity, which we found to be under strong positive selection. Ancestral state reconstruction indicated that the ancestral state at position 63 corresponds to the amino acid valine, which is present only in isolates of clade I. However, the isolates from the current outbreak contained threonine at position 63. Our findings contribute new information about the evolution of monkeypox virus.

Genomic characterization and molecular evolution of human monkeypox viruses.

Monkeypox virus is a member of the family Poxviridae, as are variola virus and vaccinia virus. It has a linear double-strand DNA genome approximately 197 kb long, containing ~190 non-overlapping ORFs. Comparison of members of the Central and West African clades shows the presence of unique genes that are associated with different disease presentations, depending on the strain. The last smallpox vaccination efforts ended in the mid-1980s, and there is concern about the recent spread of human monkeypox disease around the world. Almost 87,000 human monkeypox cases have been diagnosed in the world, of which more than 10,900 were in Brazil. The aim of this study was to evaluate the epidemiology and molecular evolution of hMpxV. From computational biology analysis of 640 hMpxV genomes from 1962 to 2022, synteny breaks and gene conservation were observed between Central and West clade genomes, and strains belonged with the 2022 outbreak assigned to the West African clade. Evidence was found for diversifying selective pressure at specific sites within protein coding sequences, acting on immunomodulatory processes. The existence of different sites under diversifying and purifying selection in paralog genes indicates adaptive mechanisms underlying the host-pathogen interaction of monkeypox virus in humans.

In vitro susceptibility of eighteen clinical isolates of human monkeypox virus to tecovirimat.

BACKGROUND: In 2022, an outbreak of mpox that started in European countries spread worldwide through human-to-human transmission. Cases have been mostly mild, but severe clinical presentations have been reported. In these cases, tecovirimat has been the drug of choice to treat patients with aggravated disease. OBJECTIVES: Here we investigated the tecovirimat susceptibility of 18 clinical isolates of monkeypox virus (MPXV) obtained from different regions of Brazil. METHODS: Different concentrations of tecovirimat were added to cell monolayers infected with each MPXV isolate. After 72 hours, cells were fixed and stained for plaque visualization, counting, and measurement. The ortholog of F13L gene from each MPXV isolate was polymerase chain reaction (PCR)-amplified, sequenced, and the predicted protein sequences were analyzed. FINDINGS: The eighteen MPXV isolates generated plaques of different sizes. Although all isolates were highly sensitive to the drug, two showed different response curves and IC50 values. However, the target protein of tecovirimat, F13 (VP37), was 100% conserved in all MPXV isolates and therefore does not explain the difference in sensitivity. MAIN CONCLUSIONS: Our results support screening different MPXV isolates for tecovirimat susceptibility as an important tool to better use of the restricted number of tecovirimat doses available in low-income countries to treat patients with mpox.

Genomic Surveillance of Monkeypox Virus, Minas Gerais, Brazil, 2022.

Phylogenetic analysis of 34 monkeypox virus genome sequences isolated from patients in Minas Gerais, Brazil, revealed initial importation events in early June 2022, then community transmission within the state. All generated genomes belonged to the B.1 lineage responsible for a global mpox outbreak. These findings can inform public health measures.

Monkeypox virus (MPXV) genomics: A mutational and phylogenomic analyses of B.1 lineages.

The recent increase in monkeypox (MPX) cases has attracted attention of public health authorities due to its quick spread and transmission across non-endemic regions. This outbreak, unlike previous ones, displays different epidemiological features and transmission dynamics, which appear to be largely influenced by the newly divergent MPX lineages (B.1). Yet, the genomic characteristics driving the high dispersal and diversification of these lineages remain largely unknown. Herein, we sought to explore and characterize the genomic features and phylogenetic diversity of the B.1 lineages through a comparative genomic analysis inclusive of 1900 high quality complete MPXV genomes. Our analyses indicate that the current MPXV-2022 outbreak encompasses thirteen derived lineages with ten unique non-synonymous mutations in several genes linked to immune evasion, virulence factors and host recognition. Such mutations may translate in the rapid evolution and diversification of current MPXV lineages. Moreover, our analyses uncovered signals of genomic modifications suggestive of immune-modulatory enzymatic activity, such as APOBEC3 editing, which, as previously suggested could have favored evolutionary trends leading to the rapid spread of MPXV into non-endemic countries. Genomic surveillance continues to play a major role in unveiling the genomic signatures signaling potential adaptation of this emerging MPXV lineage and how it will continue to impact public health in the near future.

Current Pandemic in the World: Monkeypox from Past to Present.

Monkeypox is a zoonotic viral infection that was first identified in humans in 1970 in the Democratic Republic of Congo. The cases seen again in early May 2022 have reached 78.000 as of today. On July 23, 2022, the World Health Organization decided that the monkeypox outbreak represents a public health emergency. For the early diagnosis and effective treatment of monkeypox, inter-individual transmission routes, disease symptoms, factors affecting the course of the disease, presence of another infection, prognosis, pharmacological agents used in the prophylactic treatment, and their effects, populations at risk, waste disposal protocol should be known. For this reason, our aim is to reveal the sources of transmission of the monkeypox virus from past to present, what are the signs and symptoms in patients after infection, ways of protection from the virus, the mutation status of the virus, and treatment approaches.

Viruela símica: una revisión narrativa de la fisiopatología / Monkeypox: a narrative review of pathophysiology

La viruela símica es una enfermedad zoonótica identificada por primera vez en 1958. El virus es un miembro del género Orthopoxvirus, de la familia Poxviridae. Infecta a una amplia variedad de mamíferos, pero se desconoce su reservorio natural. El virus del brote de 2022 pertenece a los clados IIa y IIb. Es probable que la aparición del brote actual se deba a las importaciones del brote de Nigeria de 2017-2018. La propagación de persona a persona puede ocurrir a través del contacto cercano con lesiones, fluidos corporales, gotitas respiratorias y objetos contaminados. Una vez dentro del organismo, el virus infecta las mucosas, células epiteliales y células inmunitarias de los tejidos adyacentes. Luego, el virus se replica y disemina rápidamente a través del sistema hemático y linfático. Las células T desempeñan un papel importante en la regulación de la respuesta inmunitaria contra el virus. Sin embargo, los Orthopoxvirus han desarrollado varios mecanismos para la evasión de la respuesta inmunitaria. La vigilancia de la enfermedad es un factor crucial en la evaluación de riesgo del virus y del control del brote. Para esta revisión se realizó la búsqueda de los principales artículos relacionados a la patogenia del virus, publicados hasta la fecha. El artículo destaca la necesidad de nuevos estudios sobre transmisibilidad y patogenicidad de las cepas asociadas al brote de 2022.

Monkeypox is a zoonotic disease first identified in 1958. The virus is a member of the genus Orthopoxvirus, family Poxviridae. It infects a wide variety of mammals, but its natural reservoir is unknown. The virus in the 2022 outbreak belongs to clades IIa and IIb. The emergence of the current outbreak is likely to be due to importations from the 2017-2018 Nigerian outbreak. Person to person spread can occur through close contact with lesions, body fluids, respiratory droplets and contaminated objects. Once inside the body, the virus infects mucous membranes, epithelial cells and immune cells in adjacent tissues. The virus then replicates and spreads rapidly through the blood and lymphatic system. Tcells play an important role in regulating the immune response against the virus. However, Orthopoxvirus have evolved several mechanisms for evasion of the immune response. Disease surveillance is a crucial factor in virus risk assessment and outbreak control. For this review we searched for the main articles related to the pathogenesis of the virus published to date. The article highlights the need for further studies on transmissibility and pathogenicity of the strains associated with the 2022 outbreak.

Metagenomic Sequencing of Monkeypox Virus, Northern Mexico.

Monkeypox virus (MPXV) has gained interest because of a multicountry outbreak of mpox (formerly monkeypox) cases with no epidemiologic link to MPXV-endemic regions. We sequenced the complete genome of MPXV isolated from a patient in northern Mexico. Phylogenetic analysis grouped the virus with isolates from Germany.

Ultrastructural analysis of monkeypox virus replication in Vero cells.

In early May 2022, the first worldwide monkeypox virus (MPXV) outbreak was reported, with different clinical aspects from previously studied human monkeypox infections. Despite monkeypox medical importance, much of its biological aspects remain to be further investigated. In the present work, we evaluated ultrastructural aspects of MPXV asynchronous infections in Vero cells by transmission electron microscopy (TEM). The viral strain was isolated from a male patient infected during the 2022 outbreak. TEM analysis showed: (i) adhered intracellular mature virus particles before entry of the host cell; (ii) a reorganization of the rough endoplasmic reticulum cisternae into the so-called "mini-nuclei" structure associated with genome replication; and (iii) noticeably different sites within the viral factory presenting granular or fibrillar aspects. We also observed viral crescents, different MPXV particle morphotypes, and cellular alterations induced by infection, such as changes in the cytoskeleton structure and multimembrane vesicles abundance. Taken together, to the best of our knowledge, these results revealed for the first-time ultrastructural aspects of different steps of the MPXV cycle.

The First Two Cases of Monkeypox Infection in MSM in Bahia, Brazil, and Viral Sequencing.

Monkeypox infection is rapidly spreading across the world. Despite the increasing number of cases, only a few reports have been published, and most are on people living without HIV. We report here the first two cases of monkeypox infection in Bahia, Brazil, one of them in a person living with HIV, on stable treatment. Both cases had a similar evolution, with a limited number of lesions and mild symptoms, with a complete recovery after 7-10 days. The potential route of transmission was via oral sex for the first case and was undefined for the second one. Both cases were confirmed through detection of the viral genome by PCR, and the partial sequence of the first case indicates the infection was caused by the West African clade. These cases confirm that monkeypox infection is currently being transmitted in Brazil and that people living with HIV on stable treatment are not likely to present a more severe form of monkeypox.

Monkeypox Virus Transmission to Healthcare Worker through Needlestick Injury, Brazil.

We describe monkeypox virus (MPXV) transmission from a patient to a healthcare worker through needlestick injury. A lesion appeared at the inoculation site 5 days after injury. Blood tested MPXV-positive by PCR before symptoms worsened; blood remained MPXV-positive at discharge 19 days after symptom onset. Postexposure prophylaxis could prevent potential MPXV bloodborne transmission.

Monkeypox virus genome sequence from an imported human case in Colombia. / Secuencia genómica del virus de la viruela símica de un caso importado en Colombia

INTRODUCTION: Monkeypox virus (MPXV) is an enveloped double-stranded DNA virus with a genome of approximately 197.209 bp. The current classification divides MPXV into three clades: Clade I (Central African or Congo Basin clade) and clades IIa and IIb (West African clades). OBJECTIVE: To report the complete genome and phylogenetic analysis of a human monkeypox case detected in Colombia. MATERIALS AND METHODS: Exudate from vesicular lesions was obtained from a male patient with recent travel history to Spain. A direct genomic approach was implemented in which total DNA from the sample was purified through a column-based method, followed by sequencing on the Nanopore GridION. Reads were aligned against the MPXV reference genome using minimap2 v.2.24 and phylogenetic inference was performed using maximum likelihood estimation. RESULTS: A total of 11.951 reads mapped directly to a reference genome with 96.8% of coverage (190.898 bp). CONCLUSION: Phylogenetic analysis of the MPXV circulating in Colombia demonstrated its close relationship to clade IIb responsible for the multi-country outbreak in 2022.

Introducción. El virus de la viruela del mono (MPXV) está compuesto por un genoma de ADN bicatenario, aproximadamente, de 197.209 pb. La clasificación actual agrupa el MPXV en tres clados: clado I (de la cuenca del Congo en África central), y clados IIa y IIb (de África occidental). Objetivo. Reportar el genoma completo y el análisis filogenético de un caso humano de viruela símica detectado en Colombia. Materiales y métodos. Se obtuvo exudado de lesiones vesiculares de un paciente varón con el antecedente de un viaje reciente a España. Se implementó un enfoque directo, en el cual se purificó el ADN total de la muestra mediante un método basado en columnas, seguido de la secuenciación directa en la plataforma Nanopore GridION. Las lecturas se alinearon con el genoma de referencia del MPXV, utilizando minimap2, v.2.24, y la inferencia filogenética fue realizada mediante la estimación por máxima verosimilitud. Resultados. Un total de 11.951 lecturas se alinearon directamente con el genoma de referencia con una cobertura del 96,8 % (190.898 pb). Conclusión. El análisis filogenético del MPXV circulante en Colombia demostró su estrecha relación con el clado de África occidental (clado IIb) responsable del brote en múltiples países en el 2022.

Sexually-transmitted monkeypox: report of two cases.

Monkeypox is an emerging infection that has spread to all continents since May 2022. It is caused by the zoonotic monkeypox virus, consisting of double-stranded DNA, belonging to the Orthopoxvirus genus of the Poxviridae family, which has high transmissibility, especially by contact with the skin, favoring its sexual transmission. This case report describes a same-sex male couple, both aged 28 years old, without comorbidities. In the index case, perioral and penile lesions started ten days before the consultation, with rapid progression and a high fever that started eight days after the appearance of the lesions. In the second case, the perioral lesions started three days after the partner; however, he remained afebrile. Both were isolated, treated with symptomatic measures, and, after ulceration, the lesions completely regressed in 14 days. Dermatologists should be aware of manifestations of monkeypox, which may include vesiculopustular lesions in areas of sexual contact, as well as oligosymptomatic cases or cases with few skin lesions.

Possible Occupational Infection of Healthcare Workers with Monkeypox Virus, Brazil.

We evaluated epidemiologic and molecular characteristics of monkeypox virus (MPXV) infections sampled from 2 healthcare nurses. Five days after collecting samples from an infected patient, the nurses showed typical MPXV manifestations; quantitative PCR and whole-genome sequencing confirmed MPXV infection, most likely transmitted through contact with fomites.

Phylogenomic analysis of the monkeypox virus (MPXV) 2022 outbreak: Emergence of a novel viral lineage?

Monkeypox is a zoonotic disease with clinical manifestations similar to smallpox in humans. Since May 13, 2022, an increasing number of suspected and confirmed cases have been reported, affecting non-endemic regions across the globe. More strikingly, reports from the current outbreak reveal unique aspects regarding transmission dynamics and an unprecedented, rapidly expanding and sustained community transmission. As demonstrated through the still-ongoing COVID-19 pandemic, genomic surveillance has been an essential resource for monitoring and tracking the evolution of pathogens of public health relevance. Herein, we performed a phylogenomic analysis of available Monkeypox virus (MPXV) genomes to determine their evolution and diversity. Our analysis revealed that all MPXV genomes grouped into three monophyletic clades: two previously characterized clades and a newly emerging clade harboring genomes from the ongoing 2022 multi-country outbreak with 286 genomes comprising the hMPXV-1A clade and the newly classified lineages: A.1 (n = 6), A.1.1 (n = 1), A.2 (n = 3) and B.1 (n = 262), where lineage B.1 includes all MPXV genomes from the 2022 outbreak. Finally, it was estimated that B.1 lineage of this clade emerged in Europe on 03/02/2022 [95%CI = 11/13/2021 to 05/10/2022]. The exceptional surge of cases and the broader geographical expansion suggest multifactorial factors as drivers of the current outbreak dynamics. Such factors may include the cessation of smallpox vaccination and its potential spread across particular networks. Integrating pertinent epidemiological information with genomic surveillance information will help generate real-time data to help implement adequate preventive and control measures by optimizing public health decisions to mitigate this outbreak.