Inverted repeats in the monkeypox virus genome are hot spots for mutation

Mpox in people with HIV: A narrative review

OBJECTIVE

The 2022 global mpox outbreak disproportionately impacted people living with HIV. This review explores recent evidence on mpox in this group, focusing on clinical presentation, complications, treatment modalities and vaccine strategies.

RECENT FINDINGS

Recent studies have suggested that people with HIV diagnosed with mpox have a greater risk of proctitis and hospitalization compared with people without HIV. In addition, those with advanced immunosuppression face an elevated risk of severe mpox infection, which can lead to mortality. Comprehensive and prompt supportive care using antiretrovirals and mpox antivirals is crucial in this group. Although results from randomized clinical trials are still forthcoming, recent studies suggest that early initiation of tecovirimat can prevent disease progression in people with HIV. The non-replicative attenuated smallpox vaccine is well tolerated and effective in preventing monkeypox virus infections in people with HIV. Further studies are needed regarding long-term vaccine effectiveness for this population.

CONCLUSION

Evaluating the risk of severe mpox in people living with HIV requires assessing the level of immune suppression and viral control. Universal access to vaccination is imperative to prevent the resurgence of future outbreaks.

"Mpox in MSM: Tackling Stigma, Minimizing Risk Factors, Exploring Pathogenesis, and Treatment Approaches"

Mpox is a zoonotic disease caused by the monkeypox virus (MPV), primarily found in Central and West African countries. The typical presentation of the disease before the 2022 mpox outbreak includes a febrile prodrome 5-13 days post-exposure, accompanied by lymphadenopathy, malaise, headache, and muscle aches. Unexpectedly, during the 2022 outbreak, several cases of atypical presentations of the disease were reported, such as the absence of prodromal symptoms and the presence of genital skin lesions suggestive of sexual transmission. As per the World Health Organization (WHO), as of March 20, 2024, 94,707 cases of mpox were reported worldwide, resulting in 181 deaths (22 in African endemic regions and 159 in non-endemic countries). The United States Centers for Disease Control and Prevention (CDC) reports a total of 32,063 cases (33.85% of total cases globally), with 58 deaths (32.04% of global deaths) due to mpox. Person-to-person transmission of mpox can occur through respiratory droplets and sustained close contact. However, during the 2022 outbreak of mpox, a high incidence of anal and perianal lesions among MSMs indicated sexual transmission of MPV as a major route of transmission. Since MSMs are disproportionately at risk for HIV transmission, this review discusses the risk factors, transmission patterns, pathogenesis, vaccine, and treatment options for mpox among MSM and people living with HIV (PLWH). Furthermore, we provide a brief perspective on the evolution of the MPV in immunocompromised people like PLWH.

Exploring Viral Genome Profile in Mpox Patients during the 2022 Outbreak, in a North-Eastern Centre of Italy

In 2022, an unprecedented outbreak of mpox raged in several nations. Sequences from the 2022 outbreak reveal a higher nucleotide substitution if compared with the estimated rate for orthopoxviruses. Recently, intra-lesion SNVs (single nucleotide variants) have been described, and these have been suggested as possible sources of genetic variation. Until now, it has not been clear if the presence of several SNVs could represents the result of local mutagenesis or a possible co-infection. We investigated the significance of SNVs through whole-genome sequencing analysis of four unrelated mpox cases. In addition to the known mutations harboured by the circulating strains of virus (MPXV), 7 novel mutations were identified, including SNVs located in genes that are involved in immune evasion mechanisms and/or viral fitness, six of these appeared to be APOBEC3-driven. Interestingly, three patients exhibited the coexistence of mutated and wild-type alleles for five non-synonymous variants. In addition, two patients, apparently unrelated, showed an analogous pattern for two novel mutations, albeit with divergent frequencies. The coexistence of mixed viral populations, harbouring non-synonymous mutations in patients, supports the hypothesis of possible co-infection. Additional investigations of larger clinical cohorts are essential to validating intra-patient viral genome heterogeneity and determining the possibility of co-presence events of slightly divergent MPXV strains.

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.

Mpox (formerly monkeypox): pathogenesis, prevention, and treatment

In 2022, a global outbreak of Mpox (formerly monkeypox) occurred in various countries across Europe and America and rapidly spread to more than 100 countries and regions. The World Health Organization declared the outbreak to be a public health emergency of international concern due to the rapid spread of the Mpox virus. Consequently, nations intensified their efforts to explore treatment strategies aimed at combating the infection and its dissemination. Nevertheless, the available therapeutic options for Mpox virus infection remain limited. So far, only a few numbers of antiviral compounds have been approved by regulatory authorities. Given the high mutability of the Mpox virus, certain mutant strains have shown resistance to existing pharmaceutical interventions. This highlights the urgent need to develop novel antiviral drugs that can combat both drug resistance and the potential threat of bioterrorism. Currently, there is a lack of comprehensive literature on the pathophysiology and treatment of Mpox. To address this issue, we conducted a review covering the physiological and pathological processes of Mpox infection, summarizing the latest progress of anti-Mpox drugs. Our analysis encompasses approved drugs currently employed in clinical settings, as well as newly identified small-molecule compounds and antibody drugs displaying potential antiviral efficacy against Mpox. Furthermore, we have gained valuable insights from the process of Mpox drug development, including strategies for repurposing drugs, the discovery of drug targets driven by artificial intelligence, and preclinical drug development. The purpose of this review is to provide readers with a comprehensive overview of the current knowledge on Mpox.

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.

Extraction-free LAMP assays for generic detection of Old World Orthopoxviruses and specific detection of Mpox virus

Mpox is a neglected zoonotic disease endemic in West and Central Africa. The Mpox outbreak with more than 90,000 cases worldwide since 2022 generated great concern about future outbreaks and highlighted the need for a simple and rapid diagnostic test. The Mpox virus, MPV, is a member of the Orthopoxvirus (OPV) genus that also contains other pathogenic viruses including variola virus, vaccinia virus, camelpox virus, and cowpox virus. Phylogenomic analysis of 200 OPV genomes identified 10 distinct phylogroups with the New World OPVs placed on a very long branch distant from the Old World OPVs. Isolates derived from infected humans were found to be distributed across multiple phylogroups interspersed with isolates from animal sources, indicating the zoonotic potential of these viruses. In this study, we developed a simple and sensitive colorimetric LAMP assay for generic detection of Old World OPVs. We also developed an MPV-specific probe that differentiates MPV from other OPVs in the N1R LAMP assay. In addition, we described an extraction-free protocol for use directly with swab eluates in LAMP assays, thereby eliminating the time and resources needed to extract DNA from the sample. Our direct LAMP assays are well-suited for low-resource settings and provide a valuable tool for rapid and scalable diagnosis and surveillance of OPVs and MPV.

An In Silico Analysis of PCR-Based Monkeypox Virus Detection Assays: A Case Study for Ongoing Clinical Surveillance

The 2022 global Mpox outbreak swiftly introduced unforeseen diversity in the monkeypox virus (MPXV) population, resulting in numerous Clade IIb sublineages. This propagation of new MPXV mutations warrants the thorough re-investigation of previously recommended or validated primers designed to target MPXV genomes. In this study, we explored 18 PCR primer sets and examined their binding specificity against 5210 MPXV genomes, representing all the established MPXV lineages. Our results indicated that only five primer sets resulted in almost all perfect matches against the targeted MPXV lineages, and the remaining primer sets all contained 1-2 mismatches against almost all the MPXV lineages. We further investigated the mismatched primer-genome pairs and discovered that some of the primers overlapped with poorly sequenced and assembled regions of the MPXV genomes, which are consistent across multiple lineages. However, we identified 173 99% genome-wide conserved regions across all 5210 MPXV genomes, representing 30 lineages/clades with at least 80% lineage-specific consensus for future primer development and primer binding evaluation. This exercise is crucial to ensure that the current detection schemes are robust and serve as a framework for primer evaluation in clinical testing development for other infectious diseases.

APOBEC3F Is a Mutational Driver of the Human Monkeypox Virus Identified in the 2022 Outbreak

BACKGROUND

On May 6, 2022, a powerful outbreak of monkeypox virus (MPXV) had been reported outside of Africa, with many continuing new cases being reported around the world. Analysis of mutations among the 2 different lineages present in the 2021 and 2022 outbreaks revealed the presence of G->A mutations occurring in the 5'GpA context, indicative of APOBEC3 cytidine deaminase activity.

METHODS

By using a sensitive polymerase chain reaction (differential DNA denaturation PCR) method allowing differential amplification of AT-rich DNA, we analyzed the level of APOBEC3-induced MPXV editing in infected cells and in patients.

RESULTS

We demonstrate that G->A hypermutated MPXV genomes can be recovered experimentally from APOBEC3 transfection followed by MPXV infection. Here, among the 7 human APOBEC3 cytidine deaminases (A3A-A3C, A3DE, A3F-A3H), only APOBEC3F was capable of extensively deaminating cytidine residues in MPXV genomes. Hyperedited genomes were also recovered in ∼42% of analyzed patients. Moreover, we demonstrate that substantial repair of these mutations occurs. Upon selection, corrected G->A mutations escaping drift loss contribute to the MPXV evolution observed in the current epidemic.

CONCLUSIONS

Stochastic or transient overexpression of the APOBEC3F gene exposes the MPXV genome to a broad spectrum of mutations that may be modeling the mutational landscape after multiple cycles of viral replication.

Addressing the resurgence of global monkeypox (Mpox) through advanced drug delivery platforms

Monkeypox (Mpox) is a transmissible infection induced by the Monkeypox virus (a double-stranded DNA virus), recognised under the family orthopoxvirus genus. Monkeypox, like endemic diseases, is a substantial concern worldwide; thus, comprehending the pathogenesis and mutagenesis of amino acids is indispensable to combat the infection. According to the World Health Organization's report, about 89 thousand cases with 160 mortalities have been reported from 114 countries worldwide. The conventional orthopoxvirus vaccines developed on live attenuated viruses exempted any clinical validation from combating monkeypox due to inadequate immunogenicity, toxicity, instability, and multiple doses. Therefore, novel drug delivery systems come into the conception with high biological and mechanical characteristics to address the resurgence of Global Monkeypox. The edges of metallic biomaterials, novel molecules, and vaccine development in targeted therapy increase the modulation of the immune response and blockage of host-virus interaction, with enhanced stability for the antigens. Thus, this review strives to comprehend the viral cell pathogenesis concerning amino acid mutagenesis and current epidemiological standards of the Monkeypox disease across the globe. Furthermore, the review also recapitulates the various clinical challenges, current therapies, and progressive nanomedicine utilisation in the Monkeypox outbreak reinforced by various clinical trial reports. The contemporary challenges of novel drug delivery systems in Monkeypox treatment cannot be overlooked, and thus, authors have outlined the future strategies to develop successful nanomedicine to combat monkeypox. Future pandemics are inevitable but can be satisfactorily handled if we comprehend the crises, innovate, and develop cutting-edge technologies, especially by delving into frontiers like nanotechnology.

Evolutionary potential of the monkeypox genome arising from interactions with human APOBEC3 enzymes

APOBEC3, an enzyme subfamily that plays a role in virus restriction by generating mutations at particular DNA motifs or mutational 'hotspots', can drive viral mutagenesis with host-specific preferential hotspot mutations contributing to pathogen variation. While previous analysis of viral genomes from the 2022 Mpox (formerly Monkeypox) disease outbreak has shown a high frequency of C>T mutations at TC motifs, suggesting recent mutations are human APOBEC3-mediated, how emerging monkeypox virus (MPXV) strains will evolve as a consequence of APOBEC3-mediated mutations remains unknown. By measuring hotspot under-representation, depletion at synonymous sites, and a combination of the two, we analyzed APOBEC3-driven evolution in human poxvirus genomes, finding varying hotspot under-representation patterns. While the native poxvirus molluscum contagiosum exhibits a signature consistent with extensive coevolution with human APOBEC3, including depletion of TC hotspots, variola virus shows an intermediate effect consistent with ongoing evolution at the time of eradication. MPXV, likely the result of recent zoonosis, showed many genes with more TC hotspots than expected by chance (over-representation) and fewer GC hotspots than expected (under-representation). These results suggest the MPXV genome: (1) may have evolved in a host with a particular APOBEC GC hotspot preference, (2) has inverted terminal repeat (ITR) regions-which may be exposed to APOBEC3 for longer during viral replication-and longer genes likely to evolve faster, and therefore (3) has a heightened potential for future human APOBEC3-meditated evolution as the virus spreads in the human population. Our predictions of MPXV mutational potential can both help guide future vaccine development and identification of putative drug targets and add urgency to the task of containing human Mpox disease transmission and uncovering the ecology of the virus in its reservoir host.

Evolutionary potential of the monkeypox genome arising from interactions with human APOBEC3 enzymes

APOBEC3, an enzyme subfamily that plays a role in virus restriction by generating mutations at particular DNA motifs or mutational "hotspots," can drive viral mutagenesis with host-specific preferential hotspot mutations contributing to pathogen variation. While previous analysis of viral genomes from the 2022 Mpox (formerly Monkeypox) disease outbreak has shown a high frequency of C>T mutations at T C motifs, suggesting recent mutations are human APOBEC3-mediated, how emerging monkeypox virus (MPXV) strains will evolve as a consequence of APOBEC3-mediated mutations remains unknown. By measuring hotspot under-representation, depletion at synonymous sites, and a combination of the two, we analyzed APOBEC3-driven evolution in human poxvirus genomes, finding varying hotspot under-representation patterns. While the native poxvirus molluscum contagiosum exhibits a signature consistent with extensive coevolution with human APOBEC3, including depletion of T C hotspots, variola virus shows an intermediate effect consistent with ongoing evolution at the time of eradication. MPXV, likely the result of recent zoonosis, showed many genes with more T C hotspots than expected by chance (over-representation) and fewer G C hotspots than expected (under-representation). These results suggest the MPXV genome: 1) may have evolved in a host with a particular APOBEC G C hotspot preference, 2) has inverted terminal repeat (ITR) regions -which may be exposed to APOBEC3 for longer during viral replication- and longer genes likely to evolve faster, and therefore 3) has a heightened potential for future human APOBEC3-meditated evolution as the virus spreads in the human population. Our predictions of MPXV mutational potential can both help guide future vaccine development and identification of putative drug targets and add urgency to the task of containing human Mpox disease transmission and uncovering the ecology of the virus in its reservoir host.

Immunogenic proteins and potential delivery platforms for mpox virus vaccine development: A rapid review

Since May 2022, the mpox virus (MPXV) has spread worldwide and become a potential threat to global public health. Vaccines are important tools for preventing MPXV transmission and infection in the population. However, there are still no available potent and applicable vaccines specifically for MPXV. Herein, we highlight several potential vaccine targets for MPVX and emphasize potent immunogens, such as M1R, E8L, H3L, A29L, A35R, and B6R proteins. These proteins can be integrated into diverse vaccine platforms to elicit powerful B-cell and T-cell responses, thereby providing protective immunity against MPXV infection. Overall, research on the MPXV vaccine targets would provide valuable information for developing timely effective MPXV-specific vaccines.

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.

Global transmission of monkeypox virus-a potential threat under the COVID-19 pandemic

Monkeypox virus (MPXV) cases have increased dramatically worldwide since May 2022. The Atlanta Center for Disease Control and Prevention (Atlanta CDC) had reported a total of 85,922 cases as of February 20^th, 2023. During the COVID-19 pandemic, MPXV has emerged as a potential public threat. MPXV transmission and prevalence must be closely monitored. In this comprehensive review, we explained the basic characteristics and transmission routes of MPXV, individuals susceptible to it, as well as highlight the impact of the behavior of men who have sex with men (MSM) and airline traveling on recent outbreaks of MPXV. We also describe the clinical implications, the prevention of MPXV, and clinical measures of viral detection.