Human monkeypox and smallpox viruses: genomic comparison

Biological characteristics, biosafety prevention and control strategies for the 2022 multi-country outbreak of monkeypox

Monkeypox is a zoonotic disease caused by the monkeypox virus (MPXV), which is a potential biological warfare agent of bioterrorism and poses the greatest threat to the world's public biosafety and health after variola virus (VARV). While the coronavirus disease 2019 (COVID-19) pandemic has not ended yet, monkeypox is spreading menacingly. The first case of monkeypox in a nonendemic country was confirmed on May 6^th, 2022, while the first imported case from Asia was found on June 21^st. There were more than 16 thousand reported cases as of July 23^rd, the day the World Health Organization (WHO) declared the global monkeypox outbreak a public health emergency of international concern (PHEIC) at the same level as smallpox and COVID-19; while there were more than 53 thousand cases as of September 1^st. Therefore, we will propose relevant biosafety prevention and control strategies after analyzing the etiology of the 2022 multi-country monkeypox outbreak from the biological feature, transmissibility, epidemic, and variability of MPXV.

The virology of human monkeypox virus (hMPXV): A brief overview

First described in 1958, the human monkeypox virus (hMPXV) is a neglected zoonotic pathogen closely associated with the smallpox virus. The virus usually spreads via close contact with the infected animal or human and has been endemic mostly in parts of the African continent. However, with the recent increase in trade, tourism, and travel, the virus has caused outbreaks in countries outside Africa. The recent outbreak in 2022 has been puzzling given the lack of epidemiological connection and the possible sexual transmission of the virus. Furthermore, there is limited understanding of the structural and pathogenetic mechanisms that are employed by the virus to invade the host cells. Henceforth, it is critical to understand the working apparatus governing the viral-immune interactions to develop effective therapeutical and prophylactic modalities. Hence, in the present short communication, we summarize the previously reported research findings regarding the virology of the human monkeypox virus.

Monkeypox in pregnancy: virology, clinical presentation, and obstetric management

The 2022 monkeypox outbreak, caused by the zoonotic monkeypox virus, has spread across 6 World Health Organization regions (the Americas, Africa, Europe, Eastern Mediterranean, Western Pacific, and South-East Asia) and was declared a public health emergency of international concern on July 23, 2022. The global situation is especially concerning given the atypically high rate of person-to-person transmission, which suggests viral evolution to an established human pathogen. Pregnant women are at heightened risk of vertical transmission of the monkeypox virus because of immune vulnerability and natural depletion of population immunity to smallpox among reproductive-age women, and because orthopoxviral cell entry mechanisms can overcome the typically viral-resistant syncytiotrophoblast barrier within the placenta. Data on pregnancy outcomes following monkeypox infection are scarce but include reports of miscarriage, intrauterine demise, preterm birth, and congenital infection. This article forecasts the issues that maternity units might face and proposes guidelines to protect the health of pregnant women and fetuses exposed to the monkeypox virus. We review the pathophysiology and clinical features of monkeypox infection and discuss the obstetrical implications of the unusually high prevalence of anogenital lesions. We describe the use of real-time polymerase chain reaction tests from mucocutaneous and oropharyngeal sites to confirm infection, and share an algorithm for the antenatal management of pregnant women with monkeypox virus exposure. On the basis of the best available knowledge from prenatal orthopoxvirus infections, we discuss the sonographic features of congenital monkeypox and the role of invasive testing in establishing fetal infection. We suggest a protocol for cesarean delivery to avoid the horizontal transmission of the monkeypox virus at birth and address the controversy of mother-infant separation in the postpartum period. Obstetrical concerns related to antiviral therapy with tecovirimat and vaccinia immune globulin are highlighted, including the risks of heart rate-corrected QT-interval prolongation, inaccuracies in blood glucose monitoring, and the predisposition to iatrogenic venous thromboembolism. The possibility of monkeypox vaccine hesitancy during pregnancy is discussed, and strategies are offered to mitigate these risks. Finally, we conclude with a research proposal to address knowledge gaps related to the impact of monkeypox infection on maternal, fetal, and neonatal health.

Monkeypox: Immune response, vaccination and preventive efforts

Infectious threats to humans are continuously emerging. The 2022 worldwide monkeypox outbreak is the latest of these threats with the virus rapidly spreading to 106 countries by the end of September 2022. The burden of the ongoing monkeypox outbreak is manifested by 68,000 cumulative confirmed cases and 26 deaths. Although monkeypox is usually a self-limited disease, patients can suffer from extremely painful skin lesions and complications can occur with reported mortalities. The antigenic similarity between the smallpox virus (variola virus) and monkeypox virus can be utilized to prevent monkeypox using smallpox vaccines; treatment is also based on antivirals initially designed to treat smallpox. However, further studies are needed to fully decipher the immune response to monkeypox virus and the immune evasion mechanisms. In this review we provide an up-to-date discussion of the current state of knowledge regarding monkeypox virus with a special focus on innate immune response, immune evasion mechanisms and vaccination against the virus.

Retrospective detection of monkeypox virus in the testes of nonhuman primate survivors

Close contact through sexual activity has been associated with the spread of monkeypox virus (MPXV) in the ongoing, global 2022 epidemic. However, it remains unclear whether MPXV replicates in the testes or is transmitted via semen to produce an active infection. We carried out a retrospective analysis of MPXV-infected crab-eating macaque archival tissue samples from acute and convalescent phases of infection of clade I or clade II MPXV using immunostaining and RNA in situ hybridization. We detected MPXV in interstitial cells and seminiferous tubules of testes as well as epididymal lumina, which are the sites of sperm production and maturation. We also detected inflammation and necrosis during the acute phase of the disease by histological analysis. Finally, we found that MPXV was cleared from most organs during convalescence, including healed skin lesions, but could be detected for up to 37 d post-exposure in the testes of convalescent macaques. Our findings highlight the potential for sexual transmission of MPXV in humans.

The Global Human Monkeypox Outbreak and Management: A Comprehensive Literature Review

Monkeypox (MPX) belongs to the genus Orthopoxvirus (OPV), family Poxviridae, and sub-family Chordopoxvirinae. Human monkeypox (HMPX) is a viral zoonotic illness caused by the monkeypox virus (MPXV). Several non-endemic countries have confirmed MPX cases across the globe. Therefore, consider an outbreak to be a global health emergency. MPXV transmits from animals to humans via infected animals, and there is currently human-to-human transmission, notably among guys who have sexual relations with males. Healthcare interventions are required to stop outbreaks. These include strict isolation and care for MPX patients while they are still contagious or until the skin lesions dry out and crust over. JYNNEOS was approved as a vaccine for the prevention of MPXV. Tecovirimat is licensed to treat severe MPX or risk developing a serious disease. We should encourage international cooperation to conduct clinical trials investigating the effectiveness and safety of MPXV vaccines and antiviral medications. Precautions must be taken at the global level to prevent an MPXV outbreak.

Comprehensive literature review of monkeypox

The current outbreak of monkeypox (MPX) infection has emerged as a global matter of concern in the last few months. MPX is a zoonosis caused by the MPX virus (MPXV), which is one of the Orthopoxvirus species. Thus, it is similar to smallpox caused by the variola virus, and smallpox vaccines and drugs have been shown to be protective against MPX. Although MPX is not a new disease and is rarely fatal, the current multi-country MPX outbreak is unusual because it is occurring in countries that are not endemic for MPXV. In this work, we reviewed the extensive literature available on MPXV to summarize the available data on the major biological, clinical and epidemiological aspects of the virus and the important scientific findings. This review may be helpful in raising awareness of MPXV transmission, symptoms and signs, prevention and protective measures. It may also be of interest as a basis for performance of studies to further understand MPXV, with the goal of combating the current outbreak and boosting healthcare services and hygiene practices.Trial registration: ClinicalTrials.gov identifier: NCT02977715..Trial registration: ClinicalTrials.gov identifier: NCT03745131..Trial registration: ClinicalTrials.gov identifier: NCT00728689..Trial registration: ClinicalTrials.gov identifier: NCT02080767..

Global Research Trends on Monkeypox Virus: A Bibliometric and Visualized Study

Monkeypox is a zoonotic viral disease that has recently emerged as another global infection disease. A double-stranded enveloped deoxyribonucleic acid virus the cause of this disease. Since monkeypox is an evolving field of study with a growing interest in public health, it is crucial to study the scientific trend and research activities. This study provides an essential insight into the research response to scientific trends of monkeypox using the bibliometric analysis technique. A literature search for published articles on LSD from 2001 to 2021 was conducted in Scopus on 24 July 2022. Visualization analysis was performed using R statistical software. The growth and trend of documents, country-level distribution of publications and collaborations, and the relationship between authors and co-authors were analyzed. Findings revealed a significant increase in the research conducted, mainly from the United States (US). The top 12 institutions published papers on the monkeypox virus, accounting for 33.09 percent of the articles. The US was the most productive nation, producing 275 documents (54.34%), or one-third of all publications in this sector worldwide. Centers for Disease Control and Prevention in Georgia in the United States were the organization that produced the most (365 publications). The Journal of Virology garnered the most citations, with an h-index of 18. In the last year, there has been an increase in the publication of monkeypox virus-related studies. The importance of the monkeypox virus highlights the necessity for continued research to help international health organizations identify areas that require prompt action to implement suitable solutions. This study also provides scaling-up analysis, evidence dissemination on the monkeypox virus, emerging hotspots, and perceptive remarks on the technological advances in this field.

Whole-Genome Sequences of Human Monkeypox Virus Strains from Two 2022 Global Outbreak Cases in Western New York State

The genomes of two human monkeypox virus strains from recently reported cases in our local region that were associated with the 2022 global outbreak were sequenced. Genomes from clinical isolates provide valuable information for epidemiological tracking and analysis of strain evolution and can be especially important during the early phases of outbreaks.

Identification of Antiviral Compounds against Monkeypox Virus Profilin-like Protein A42R from Plantago lanceolata

Infections caused by the monkeypox virus (MPXV) have continued to be transmitted significantly in recent years. However, understanding the transmission mechanism, risk factors, and consequences of infection are still limited. Structure-based drug design for MPXV is at an early stage due to the availability of protein structures that have been determined experimentally. However, the structure of the A42R profilin-like protein of MPXV has been solved and submitted to the structure database. This study illustrated an in silico structure-based approach to identify the potential hit compound against A42R of MPXV. Here, 65 Plantago lanceolata compounds were computationally screened against A42R of MPXV. Virtual screening identified top five hits (i) Luteolin 7,3′-Diglucuronide (PubChem ID: 44258091), (ii) Luteolin 7-Glucuronide-3′-Glucoside (PubChem ID: 44258090), (iii) Plantagoside (PubChem ID: 174157), (iv) Narcissoside (PubChem ID: 5481663), and (v) (AlphaE,8S,9R)-N-(3,4-Dihydroxyphenethyl)-8-[(3,4-Dihydroxyphenethyl)Carbamoyl]-9-(1,3-Benzodioxole-5-Yl)-3aalpha,7aalpha-Ethano-1,3-Benzodioxole-5-Acrylamide (PubChem ID: 101131595), with binding energy <−9.0 kcal/mol that was further validated by re-docking and molecular dynamic (MD) simulation. Interaction analysis of re-docked poses confirmed the binding of these top hits to the A42R protein as reported in the reference compound, including active residues ARG114, ARG115, and ARG119. Further, MD simulation and post-simulation analysis support Plantagoside and Narcissoside for substantial stability in the binding pocket of viral protein contributed by hydrogen and hydrophobic interactions. The compounds can be considered for further optimisation and in vitro experimental validation for anti-monkeypox drug development.

Monkeypox: epidemiology, pathogenesis, treatment and prevention

Monkeypox is a zoonotic disease that was once endemic in west and central Africa caused by monkeypox virus. However, cases recently have been confirmed in many nonendemic countries outside of Africa. WHO declared the ongoing monkeypox outbreak to be a public health emergency of international concern on July 23, 2022, in the context of the COVID-19 pandemic. The rapidly increasing number of confirmed cases could pose a threat to the international community. Here, we review the epidemiology of monkeypox, monkeypox virus reservoirs, novel transmission patterns, mutations and mechanisms of viral infection, clinical characteristics, laboratory diagnosis and treatment measures. In addition, strategies for the prevention, such as vaccination of smallpox vaccine, is also included. Current epidemiological data indicate that high frequency of human-to-human transmission could lead to further outbreaks, especially among men who have sex with men. The development of antiviral drugs and vaccines against monkeypox virus is urgently needed, despite some therapeutic effects of currently used drugs in the clinic. We provide useful information to improve the understanding of monkeypox virus and give guidance for the government and relative agency to prevent and control the further spread of monkeypox virus.

Study on the Vaccination of the Population of Romania against Monkeypox in Terms of Medical Security

Although it has been shown in numerous studies that immunization of the population by vaccination is the most effective way to protect against smallpox or other polioviruses, the anti-vaccination public rhetoric recorded during the COVID-19 pandemic is likely to influence the populations acceptance of vaccination against newly emerging viruses. This fact influenced our decision to study the vaccination of the Romanian population against the virus that causes monkeypox, aiming to identify the degree of compliance regarding the decision related to vaccination acceptance/non-acceptance/hesitation, based on the survey of a representative sample of respondents. The study is based on an online questionnaire completed between 1 July and 31 July 2022 by 820 individuals, aged 18 years or above, with a permanent residency in Romania. The study was undertaken in order to observe the attitudes of the respondents regarding the acceptance, refusal, or hesitation of vaccination against monkeypox. The sociological data resulting from the application of the questionnaire on 820 people highlighted that 97.16% were vaccinated with the vaccines of the national mandatory scheme and 53.32% were vaccinated with the optional vaccines (rotavirus vaccine, anti-hepatitis A, meningococcal vaccine, etc.). Although 47.13% of respondents considered monkeypox to be a real problem facing humanity today, only 26.37% of those surveyed expressed their fear of becoming infected, and 29.30% were willing to immunize themselves against the virus by vaccination. Only 19.59% of respondents believed that the monkeypox disease will generate a new global pandemic, while 31.86% considered pandemics to be a human security issue, and 30.28% expressed their desire to accept a reduction in some rights and freedoms, in the short term, for the adoption of institutional measures to combat a possible pandemic caused by monkeypox. The study clearly highlights the fact that monkeypox is perceived as a threat to the health of the population, with relatively low acceptance of conspiracy theories regarding its origins/manifestation/consequences among respondents (between 21.7% and 28.9%). The vaccination of the population against monkeypox is strongly influenced by the validity of the results obtained over time, in the vaccination campaigns against the smallpox virus (vaccine found in the mandatory vaccination scheme in Romania until 1979). We believe that the negative public rhetoric regarding the COVID-19 vaccination is likely to negatively influence monkeypox vaccination. Although specialized studies and practical results showed that the immunization of the population through vaccination represents an important vector in the prevention/management of pandemic-type issues, we believe that a national pro-vaccination campaign, based on scientific evidence, can lead the population to accept vaccination when the epidemiological context requires it. We also believe that a culture of health security needs to be developed among citizens to raise awareness of the role of vaccines as an important vector in the field of population health.

Structure of the Monkeypox virus profilin-like protein A42R reveals potential functional differences from cellular profilins

The infectious disease human monkeypox is spreading rapidly in 2022, causing a global health crisis. The genomics of Monkeypox virus (MPXV) have been extensively analyzed and reported, although little is known about the virus-encoded proteome. In particular, there are no reported experimental MPXV protein structures other than computational models. Here, a 1.52 Å resolution X-ray structure of the MPXV protein A42R, the first MPXV-encoded protein with a known structure, is reported. A42R shows structural similarity to profilins, which are cellular proteins that are known to function in the regulation of actin cytoskeletal assembly. However, structural comparison of A42R with known members of the profilin family reveals critical differences that support prior biochemical findings that A42R only weakly binds actin and does not bind poly(L-proline). In addition, the analysis suggests that A42R may make distinct interactions with phosphatidylinositol lipids. Overall, the data suggest that the role of A42R in the replication of orthopoxviruses may not be readily determined by comparison to cellular profilins. Furthermore, these findings support the need for increased efforts to determine high-resolution structures of other MPXV proteins to inform physiological studies of the poxvirus infection cycle and to reveal potential new strategies to combat human monkeypox should this emerging infectious disease with pandemic potential become more common in the future.

Monkeypox: disease epidemiology, host immunity and clinical interventions

Monkeypox virus (MPXV), which causes disease in humans, has for many years been restricted to the African continent, with only a handful of sporadic cases in other parts of the world. However, unprecedented outbreaks of monkeypox in non-endemic regions have recently taken the world by surprise. In less than 4 months, the number of detected MPXV infections has soared to more than 48,000 cases, recording a total of 13 deaths. In this Review, we discuss the clinical, epidemiological and immunological features of MPXV infections. We also highlight important research questions and new opportunities to tackle the ongoing monkeypox outbreak.

Monkeypox virus: An emerging epidemic

INTRODUCTION

A monkeypox outbreak is spreading in territories where the virus is not generally prevalent. The rapid and sudden emergence of monkeypox in numerous nations at the same time means that unreported transmission may have persisted. The number of reported cases is on a constant increase worldwide. At least 20 non-African countries, like Canada, Portugal, Spain, and the United Kingdom, have reported more than 57662 as of September 9th suspected or confirmed cases. This is the largest epidemic seen outside of Africa. Scientists are struggling to determine the responsible genes for the higher virulence and transmissibility of the virus. Because the viruses are related, several countries have begun acquiring smallpox vaccinations, which are believed to be very effective against monkeypox.

METHODS

Bibliographic databases and web-search engines were used to retrieve studies that assessed monkeypox basic biology, life cycle, and transmission. Data were evaluated and used to explain the therapeutics that are under use or have potential. Finally, here is a comparison between how vaccines are being made now and how they were made in the past to stop the spread of new viruses.

CONCLUSIONS

Available vaccines are believed to be effective if administered within four days of viral exposure, as the virus has a long incubation period. As the virus is zoonotic, there is still a great deal of concern about the viral genetic shift and the risk of spreading to humans. This review will discuss the virus's biology and how dangerous it is. It will also look at how it spreads, what vaccines and treatments are available, and what technologies could be used to make vaccines quickly using mRNA technologies.

Global Outbreak of Human Monkeypox in 2022: Update of Epidemiology

Background: Human monkeypox was a neglected zoonotic disease considered endemic to rainforests of rural parts of Central and Western Africa, until a global outbreak in May 2022. Methods: This review describes the epidemiological characteristics of human monkeypox. Results: Since the first confirmed case in the United Kingdom on 13 May 2022, and up until 19 September, more than 62,000 cases of human monkeypox were reported in 104 countries in the world (among them 97 countries where the monkeypox virus was not endemic). Up to today, 20 persons have died in this global outbreak. This outbreak predominantly affects men self-identifying as gay or bisexual or other men who have sex with men, and for now, there is no sign of continuous transmission of the disease in other populations. Today, the monkeypox outbreak is increasing alarmingly in many countries and presents a new challenge and a large issue for public health worldwide. The World Health Organization declared the global monkeypox outbreak a public health emergency of international concern on 24 July 2022. Before this outbreak, health professionals in many countries had a knowledge gap and a lack of experience in the management of monkeypox. Conclusions: Advances in the comprehension of the epidemiology of human monkeypox are necessary for effective prevention and outbreak response.

Monkeypox virus genome sequence from an imported human case in 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.

Human monkeypox: A review of the literature

Monkeypox (MPX) has recently made international headlines for the rapid and simultaneous progression of the disease across the world. This review aims at summarizing the literature available as well as describing the evolution of the disease as it pertains to the cases today along with potential treatments and infection control strategies. To date, more than 76 countries have reported cases in more than 12,261 people. Before this, MPX was a rare zoonotic disease confined to endemic areas in Western and Central Africa with sporadic outbreaks namely in the United States, associated with the import of wild animals from Ghana. However, during the current outbreak, human-to-human transmission has become the primary mode of transmission, raising concerns for unaccounted community spread. Most of these patients did not travel to the endemic areas of Africa, suggesting possible previously underdetected community transmission. Observations from emergent cases have reported that the manifestations of the disease were sometimes atypical from what has been previously described. Young men who have sex with men seem to be the population most vulnerable to infection. Though the disease is currently perceived to be mild in its clinical course, questions that remain unclear and warrant further investigation include potential of humans harboring a genital reservoir of the virus and the possibility of airborne transmission, which has implications for infection control and health of the community at large.

Comparison of Transcriptomic Signatures between Monkeypox-Infected Monkey and Human Cell Lines

Monkeypox virus (MPV) is a smallpox-like virus belonging to the genus Orthopoxvirus of the family Poxviridae. Unlike smallpox with no animal reservoir identified and patients suffering from milder symptoms with less mortality, several animals were confirmed to serve as natural hosts of MPV. The reemergence of a recently reported monkeypox epidemic outbreak in nonendemic countries has raised concerns about a global outburst. Since the underlying mechanism of animal-to-human transmission remains largely unknown, comprehensive analyses to discover principal differences in gene signatures during disease progression have become ever more critical. In this study, two MPV-infected in vitro models, including human immortal epithelial cancer (HeLa) cells and rhesus monkey (Macaca mulatta) kidney epithelial (MK2) cells, were chosen as the two subjects to identify alterations in gene expression profiles, together with co-regulated genes and pathways that are affected during monkeypox disease progression. Using Gene Ontology (GO), Kyoto Encyclopedia of Genes and Genomes (KEGG), and MetaCore analyses, we discovered that elevated expression of genes associated with interleukins (ILs), G protein-coupled receptors (GPCRs), heat shock proteins (HSPs), Toll-like receptors (TLRs), and metabolic-related pathways play major roles in disease progression of both monkeypox-infected monkey MK2 and human HeLa cell lines. Interestingly, our analytical results also revealed that a cluster of differentiation 40 (CD40), plasmin, and histamine served as major regulators in the monkeypox-infected monkey MK2 cell line model, while interferons (IFNs), macrophages, and neutrophil-related signaling pathways dominated the monkeypox-infected human HeLa cell line model. Among immune pathways of interest, apart from traditional monkeypox-regulated signaling pathways such as nuclear factor- (NF-κB), mitogen-activated protein kinases (MAPKs), and tumor necrosis factors (TNFs), we also identified highly significantly expressed genes in both monkey and human models that played pivotal roles during the progression of monkeypox infection, including CXCL1, TNFAIP3, BIRC3, IL6, CCL2, ZC3H12A, IL11, CSF2, LIF, PTX3, IER3, EGR1, ADORA2A, and DUOX1, together with several epigenetic regulators, such as histone cluster family gene members, HIST1H3D, HIST1H2BJ, etc. These findings might contribute to specific underlying mechanisms related to the pathophysiology and provide suggestions regarding modes of transmission, post-infectious sequelae, and vaccine development for monkeypox in the future.

In Silico Repurposed Drugs against Monkeypox Virus

Monkeypox is an emerging epidemic of concern. The disease is caused by the monkeypox virus and an increasing global incidence with a 2022 outbreak that has spread to Europe amid the COVID-19 pandemic. The new outbreak is associated with novel, previously undiscovered mutations and variants. Currently, the US Food and Drug Administration (FDA) approved poxvirus treatment involves the use of tecovirimat. However, there is otherwise limited pharmacopoeia and research interest in monkeypox. In this study, virtual screening and molecular dynamics were employed to explore the potential repurposing of multiple drugs previously approved by the FDA or other jurisdictions for other applications. Several drugs are predicted to tightly bind to viral proteins, which are crucial in viral replication, including molecules which show high potential for binding the monkeypox D13L capsid protein, whose inhibition has previously been demonstrated to suppress viral replication.

Current efforts and challenges facing responses to Monkeypox in United Kingdom

Despite the extraordinary and exceptional advances in drugs and vaccine development, sophisticated diagnostic facilities in health care settings, strategies in disease prevention and control, emerging and re-emerging infections are still the leading cause of death and suffering amongst human and animal populations with great impact on the world economy. Monkeypox is a viral disease with the potential to spread across the globe through international travel and movements of animals from endemic areas to susceptible populations. Monkeypox virus is an uncommon but endemic viral disease in Africa, but recent outbreaks occurred in Europe, the US, UK, Spain, Portugal, Sweden, and Italy. There is a need to refurbish the healthcare settings and get prepared for future outbreaks, especially in developing countries with poor healthcare delivery services. Scientists and researchers should also focus on developing vaccines, treatment, and preventive measures before the virus spread further.

Monkeypox: A New Threat?

The global vaccination programme against smallpox led to its successful eradication and averted millions of deaths. Monkeypox virus (MPXV) is a close relative of the Variola (smallpox) virus. Due to antigenic similarity, smallpox vaccines cross-protect against MPXV. However, over 70% of people living today were never vaccinated against smallpox. Symptoms of monkeypox (MPX) include fever, head- and muscle ache, lymphadenopathy and a characteristic rash that develops into papules, vesicles and pustules which eventually scab over and heal. MPX is less often fatal (case fatality rates range from <1% to up to 11%) than smallpox (up to 30%). MPXV is endemic in sub-Saharan Africa, infecting wild animals and causing zoonotic outbreaks. Exotic animal trade and international travel, combined with the increasing susceptibility of the human population due to halted vaccination, facilitated the spread of MPXV to new areas. The ongoing outbreak, with >10,000 cases in >50 countries between May and July 2022, shows that MPXV can significantly spread between people and may thus become a serious threat to public health with global consequences. Here, we summarize the current knowledge about this re-emerging virus, discuss available strategies to limit its spread and pathogenicity and evaluate its risk to the human population.

Nanopore sequencing of a monkeypox virus strain isolated from a pustular lesion in the Central African Republic

Monkeypox is an emerging and neglected zoonotic disease whose number of reported cases has been gradually increasing in Central Africa since 1980. This disease is caused by the monkeypox virus (MPXV), which belongs to the genus Orthopoxvirus in the family Poxviridae. Obtaining molecular data is particularly useful for establishing the relationships between the viral strains involved in outbreaks in countries affected by this disease. In this study, we evaluated the use of the MinION real-time sequencer as well as different polishing tools on MinION-sequenced genome for sequencing the MPXV genome originating from a pustular lesion in the context of an epidemic in a remote area of the Central African Republic. The reads corresponding to the MPXV genome were identified using two taxonomic classifiers, Kraken2 and Kaiju. Assembly of these reads led to a complete sequence of 196,956 bases, which is 6322 bases longer than the sequence previously obtained with Illumina sequencing from the same sample. The comparison of the two sequences showed mainly indels at the homopolymeric regions. However, the combined use of Canu with specific polishing tools such as Medaka and Homopolish was the best combination that reduced their numbers without adding mismatches. Although MinION sequencing is known to introduce a number of characteristic errors compared to Illumina sequencing, the new polishing tools allow a better-quality MinION-sequenced genome, thus to be used to help determine strain origin through phylogenetic analysis.

Preparedness for a monkeypox outbreak

In light of the ongoing COVID-19 pandemic, the unexpected outbreak and worldwide spread of monkeypox has gained global attention. As of June 22, 2022, there were 3340 confirmed cases of monkeypox globally, which is the largest and most widespread monkeypox epidemic outside Africa. Monkeypox virus (MPXV) is transmitted from human-to-human through direct contact with infectious skin or mucosal skin lesions, respiratory droplets, or indirect contact with contaminated objects or materials, as well as mother-to-child vertical transmission. It is also possibly sexually transmitted through semen/vaginal fluid, and the possibility of community transmission cannot be ruled out. Monkeypox is a viral zoonotic disease caused by MPXV, which is an enveloped, linear, double-stranded DNA virus belonging to the Orthopoxvirus genus, of the Chordopoxvirinae subfamily, within the Poxviridae family. Monkeypox is usually a self-limiting infection, with symptoms lasting 2-4 weeks, and has a fatality rate that has historically fluctuated from 0% to 11%. Symptoms of monkeypox include intense headaches, fever, lesions, and lymphadenopathy. Although there is no specific treatment or vaccine for MPXV infection, antiviral drugs and vaccines for smallpox have been approved for use in several countries in response to the monkeypox outbreak. Before the virus can be allowed to establish efficient person-to-person transmission, rapid action must be taken to contain the local spread and, by extension, the multi-country outbreak of monkeypox.

[We should be prepared to smallpox re-emergence.]

The review contains a brief analysis of the results of investigations conducted during 40 years after smallpox eradication and directed to study genomic organization and evolution of variola virus (VARV) and development of modern diagnostics, vaccines and chemotherapies of smallpox and other zoonotic orthopoxviral infections of humans. Taking into account that smallpox vaccination in several cases had adverse side effects, WHO recommended ceasing this vaccination after 1980 in all countries of the world. The result of this decision is that the mankind lost the collective immunity not only to smallpox, but also to other zoonotic orthopoxvirus infections. The ever more frequently recorded human cases of zoonotic orthopoxvirus infections force to renew consideration of the problem of possible smallpox reemergence resulting from natural evolution of these viruses. Analysis of the available archive data on smallpox epidemics, the history of ancient civilizations, and the newest data on the evolutionary relationship of orthopoxviruses has allowed us to hypothesize that VARV could have repeatedly reemerged via evolutionary changes in a zoonotic ancestor virus and then disappeared because of insufficient population size of isolated ancient civilizations. Only the historically last smallpox pandemic continued for a long time and was contained and stopped in the 20th century thanks to the joint efforts of medics and scientists from many countries under the aegis of WHO. Thus, there is no fundamental prohibition on potential reemergence of smallpox or a similar human disease in future in the course of natural evolution of the currently existing zoonotic orthopoxviruses. Correspondingly, it is of the utmost importance to develop and widely adopt state-of-the-art methods for efficient and rapid species-specific diagnosis of all orthopoxvirus species pathogenic for humans, VARV included. It is also most important to develop new safe methods for prevention and therapy of human orthopoxvirus infections.

Variola virus genome sequenced from an eighteenth-century museum specimen supports the recent origin of smallpox

Smallpox, caused by the variola virus (VARV), was a highly virulent disease with high mortality rates causing a major threat for global human health until its successful eradication in 1980. Despite previously published historic and modern VARV genomes, its past dissemination and diversity remain debated. To understand the evolutionary history of VARV with respect to historic and modern VARV genetic variation in Europe, we sequenced a VARV genome from a well-described eighteenth-century case from England (specimen P328). In our phylogenetic analysis, the new genome falls between the modern strains and another historic strain from Lithuania, supporting previous claims of larger diversity in early modern Europe compared to the twentieth century. Our analyses also resolve a previous controversy regarding the common ancestor between modern and historic strains by confirming a later date around the seventeenth century. Overall, our results point to the benefit of historic genomes for better resolution of past VARV diversity and highlight the value of such historic genomes from around the world to further understand the evolutionary history of smallpox as well as related diseases. This article is part of the theme issue 'Insights into health and disease from ancient biomolecules'.

CRISPR/Cas9 as an antiviral against Orthopoxviruses using an AAV vector

A vaccine for smallpox is no longer administered to the general public, and there is no proven, safe treatment specific to poxvirus infections, leaving people susceptible to infections by smallpox and other zoonotic Orthopoxviruses such as monkeypox. Using vaccinia virus (VACV) as a model organism for other Orthopoxviruses, CRISPR-Cas9 technology was used to target three essential genes that are conserved across the genus, including A17L, E3L, and I2L. Three individual single guide RNAs (sgRNAs) were designed per gene to facilitate redundancy in rendering the genes inactive, thereby reducing the reproduction of the virus. The efficacy of the CRISPR targets was tested by transfecting human embryonic kidney (HEK293) cells with plasmids encoding both SaCas9 and an individual sgRNA. This resulted in a reduction of VACV titer by up to 93.19% per target. Following the verification of CRISPR targets, safe and targeted delivery of the VACV CRISPR antivirals was tested using adeno-associated virus (AAV) as a packaging vector for both SaCas9 and sgRNA. Similarly, AAV delivery of the CRISPR antivirals resulted in a reduction of viral titer by up to 92.97% for an individual target. Overall, we have identified highly specific CRISPR targets that significantly reduce VACV titer as well as an appropriate vector for delivering these CRISPR antiviral components to host cells in vitro.

Ectromelia-encoded virulence factor C15 specifically inhibits antigen presentation to CD4+ T cells post peptide loading

Smallpox and monkeypox pose severe threats to human health. Other orthopoxviruses are comparably virulent in their natural hosts, including ectromelia, the cause of mousepox. Disease severity is linked to an array of immunomodulatory proteins including the B22 family, which has homologs in all pathogenic orthopoxviruses but not attenuated vaccine strains. We demonstrate that the ectromelia B22 member, C15, is necessary and sufficient for selective inhibition of CD4+ but not CD8+ T cell activation by immunogenic peptide and superantigen. Inhibition is achieved not by down-regulation of surface MHC- II or co-stimulatory protein surface expression but rather by interference with antigen presentation. The appreciable outcome is interference with CD4+ T cell synapse formation as determined by imaging studies and lipid raft disruption. Consequently, CD4+ T cell activating stimulus shifts to uninfected antigen-presenting cells that have received antigen from infected cells. This work provides insight into the immunomodulatory strategies of orthopoxviruses by elucidating a mechanism for specific targeting of CD4+ T cell activation, reflecting the importance of this cell type in control of the virus.

Human monkeypox - After 40 years, an unintended consequence of smallpox eradication

Smallpox eradication, coordinated by the WHO and certified 40 years ago, led to the cessation of routine smallpox vaccination in most countries. It is estimated that over 70% of the world's population is no longer protected against smallpox, and through cross-immunity, to closely related orthopox viruses such as monkeypox. Monkeypox is now a re-emerging disease. Monkeypox is endemic in as yet unconfirmed animal reservoirs in sub-Saharan Africa, while its human epidemiology appears to be changing. Monkeypox in small animals imported from Ghana as exotic pets was at the origin of an outbreak of human monkeypox in the USA in 2003. Travellers infected in Nigeria were at the origin of monkeypox cases in the UK in 2018 and 2019, Israel in 2018 and Singapore in2019. Together with sporadic reports of human infections with other orthopox viruses, these facts invite speculation that emergent or re-emergent human monkeypox might fill the epidemiological niche vacated by smallpox. An ad-hoc and unofficial group of interested experts met to consider these issues at Chatham House, London in June 2019, in order to review available data and identify monkeypox-related research gaps. Gaps identified by the experts included:The experts further agreed on the need for a better understanding of the genomic evolution and changing epidemiology of orthopox viruses, the usefulness of in-field genomic diagnostics, and the best disease control strategies, including the possibility of vaccination with new generation non-replicating smallpox vaccines and treatment with recently developed antivirals.

Human Monkeypox: Epidemiologic and Clinical Characteristics, Diagnosis, and Prevention

Recently, concern has been raised about the emergence of human monkeypox virus and the occasionally severe clinical presentation bearing resemblance to that of smallpox. In 2018 3 patients in the UK were diagnosed with monkeypox, and the frequency and geographic distribution of cases across West and Central Africa have increased in recent years. In Nigeria, most monkeypox patients are aged <40 years and lack cross-protective immunity because they were born after discontinuation of the smallpox eradication campaign. This article reviews the epidemiology, clinical features, and management of monkeypox and discusses its growing public health threat in this context.

A review of the monkeypox virus and a recent outbreak of skin rash disease in Nigeria

Since the eradication of smallpox approximately 39 years ago, monkeypox virus remains the most pathogenic poxvirus, being mainly restricted to Central and West Africa. Before 1970, there were no reports of human monkeypox in Nigeria, while between 1971 and 1978 there were three cases, with none having been reported thereafter. However, in September 2017, a case of contagious skin rash disease, typical of monkeypox, was observed in an 11-year-old boy from the southern part of the country and confirmed to be associated with the monkeypox virus. This large outbreak consisted of 262 suspected, 115 confirmed cases, and 7 mortalities across 26 states and the Federal Capital Territory (FCT), Abuja. The aim of this manuscript is to provide an updated, comprehensive, and timely review of monkeypox, an important emerging infection in Nigeria. Monkeypox is now a major threat to global health security, requiring an urgent multidisciplinary approach involving veterinarians, physicians, virologists, and public health experts to fast-track the development of diagnostic assays, vaccines, antivirals, and other control strategies.

Monkeypox - Enhancing public health preparedness for an emerging lethal human zoonotic epidemic threat in the wake of the smallpox post-eradication era

The identification of monkeypox in 3 separate patients in the United Kingdom in September raised media and political attention on an emerging public health threat. Nigeria, whose last confirmed case of monkeypox was in 1978, is currently experiencing an unusually large and outbreak of human monkeypox cases, a 'One Human-Environmental-Animal Health' approach is being effectively used to define and tackle the outbreak. As of 13th October 2018, there have been one hundred and sixteen confirmed cases the majority of whom are under 40 years. Over the past 20 years ten Central and West African countries have reported monkeypox cases which have risen exponentially. We review the history and evolution of monkeypox outbreaks in Africa and USA, the changing clinical presentations, and discuss possible factors underlying the increasing numbers being detected including the cessation of smallpox vaccination programs. Major knowledge gaps remain on the epidemiology, host reservoir, and emergence, transmission, pathogenesis and prevention of monkeypoz.

Evolution of Synonymous Codon Usage Bias in West African and Central African Strains of Monkeypox Virus

The evolution of bias in synonymous codon usage in chosen monkeypox viral genomes and the factors influencing its diversification have not been reported so far. In this study, various trends associated with synonymous codon usage in chosen monkeypox viral genomes were investigated, and the results are reported. Identification of factors that influence codon usage in chosen monkeypox viral genomes was done using various codon usage indices, such as the relative synonymous codon usage, the effective number of codons, and the codon adaptation index. The Spearman rank correlation analysis and a correspondence analysis were used for correlating various factors with codon usage. The results revealed that mutational pressure due to compositional constraints, gene expression level, and selection at the codon level for utilization of putative optimal codons are major factors influencing synonymous codon usage bias in monkeypox viral genomes. A cluster analysis of relative synonymous codon usage values revealed a grouping of more virulent strains as one major cluster (Central African strains) and a grouping of less virulent strains (West African strains) as another major cluster, indicating a relationship between virulence and synonymous codon usage bias. This study concluded that a balance between the mutational pressure acting at the base composition level and the selection pressure acting at the amino acid level frames synonymous codon usage bias in the chosen monkeypox viruses. The natural selection from the host does not seem to have influenced the synonymous codon usage bias in the analyzed monkeypox viral genomes.

40 Years without Smallpox

The last case of natural smallpox was recorded in October, 1977. It took humanity almost 20 years to achieve that feat after the World Health Organization had approved the global smallpox eradication program. Vaccination against smallpox was abolished, and, during the past 40 years, the human population has managed to lose immunity not only to smallpox, but to other zoonotic orthopoxvirus infections as well. As a result, multiple outbreaks of orthopoxvirus infections in humans in several continents have been reported over the past decades. The threat of smallpox reemergence as a result of evolutionary transformations of these zoonotic orthopoxviruses exists. Modern techniques for the diagnostics, prevention, and therapy of smallpox and other orthopoxvirus infections are being developed today.

Immunoglobulin superfamily members encoded by viruses and their multiple roles in immune evasion

Pathogens have developed a plethora of strategies to undermine host immune defenses in order to guarantee their survival. For large DNA viruses, these immune evasion mechanisms frequently rely on the expression of genes acquired from host genomes. Horizontally transferred genes include members of the immunoglobulin superfamily, whose products constitute the most diverse group of proteins of vertebrate genomes. Their promiscuous immunoglobulin domains, which comprise the building blocks of these molecules, are involved in a large variety of functions mediated by ligand-binding interactions. The flexible structural nature of the immunoglobulin domains makes them appealing targets for viral capture due to their capacity to generate high functional diversity. Here, we present an up-to-date review of immunoglobulin superfamily gene homologs encoded by herpesviruses, poxviruses, and adenoviruses, that include CD200, CD47, Fc receptors, interleukin-1 receptor 2, interleukin-18 binding protein, CD80, carcinoembryonic antigen-related cell adhesion molecules, and signaling lymphocyte activation molecules. We discuss their distinct structural attributes, binding properties, and functions, shaped by evolutionary pressures to disarm specific immune pathways. We include several novel genes identified from extensive genome database surveys. An understanding of the properties and modes of action of these viral proteins may guide the development of novel immune-modulatory therapeutic tools.

Varicella Coinfection in Patients with Active Monkeypox in the Democratic Republic of the Congo

From 2006 to 2007, an active surveillance program for human monkeypox (MPX) in the Democratic Republic of the Congo identified 151 cases of coinfection with monkeypox virus and varicella zoster virus from 1158 suspected cases of human MPX (13%). Using clinical and socio-demographic data collected with standardized instruments by trained, local nurse supervisors, we examined a variety of hypotheses to explain the unexpectedly high proportion of coinfections among the sample, including the hypothesis that the two viruses occur independently. The probabilities of disease incidence and selection necessary to yield the observed sample proportion of coinfections under an assumption of independence are plausible given what is known and assumed about human MPX incidence. Cases of human MPX are expected to be underreported, and more coinfections are expected with improved surveillance.

Are We Prepared in Case of a Possible Smallpox-Like Disease Emergence?

Smallpox was the first human disease to be eradicated, through a concerted vaccination campaign led by the World Health Organization. Since its eradication, routine vaccination against smallpox has ceased, leaving the world population susceptible to disease caused by orthopoxviruses. In recent decades, reports of human disease from zoonotic orthopoxviruses have increased. Furthermore, multiple reports of newly identified poxviruses capable of causing human disease have occurred. These facts raise concerns regarding both the opportunity for these zoonotic orthopoxviruses to evolve and become a more severe public health issue, as well as the risk of Variola virus (the causative agent of smallpox) to be utilized as a bioterrorist weapon. The eradication of smallpox occurred prior to the development of the majority of modern virological and molecular biological techniques. Therefore, there is a considerable amount that is not understood regarding how this solely human pathogen interacts with its host. This paper briefly recounts the history and current status of diagnostic tools, vaccines, and anti-viral therapeutics for treatment of smallpox disease. The authors discuss the importance of further research to prepare the global community should a smallpox-like virus emerge.

Monkeypox virus induces the synthesis of less dsRNA than vaccinia virus, and is more resistant to the anti-poxvirus drug, IBT, than vaccinia virus

Monkeypox virus (MPXV) infection fails to activate the host anti-viral protein, PKR, despite lacking a full-length homologue of the vaccinia virus (VACV) PKR inhibitor, E3. Since PKR can be activated by dsRNA produced during a viral infection, we have analyzed the accumulation of dsRNA in MPXV-infected cells. MPXV infection led to less accumulation of dsRNA than VACV infection. Because in VACV infections accumulation of abnormally low amounts of dsRNA is associated with mutations that lead to resistance to the anti-poxvirus drug isatin beta-thiosemicarbazone (IBT), we investigated the effects of treatment of MPXV-infected cells with IBT. MPXV infection was eight-fold more resistant to IBT than wild-type vaccinia virus (wtVACV). These results demonstrate that MPXV infection leads to the accumulation of less dsRNA than wtVACV, which in turn likely leads to a decreased capacity for activation of the dsRNA-dependent host enzyme, PKR.

Evasion of the Innate Immune Type I Interferon System by Monkeypox Virus

The vaccinia virus (VACV) E3 protein has been shown to be important for blocking activation of the cellular innate immune system and allowing viral replication to occur unhindered. Mutation or deletion of E3L severely affects viral host range and pathogenesis. While the monkeypox virus (MPXV) genome encodes a homologue of the VACV E3 protein, encoded by the F3L gene, the MPXV gene is predicted to encode a protein with a truncation of 37 N-terminal amino acids. VACV with a genome encoding a similarly truncated E3L protein (VACV-E3LΔ37N) has been shown to be attenuated in mouse models, and infection with VACV-E3LΔ37N has been shown to lead to activation of the host antiviral protein kinase R pathway. In this report, we present data demonstrating that, despite containing a truncated E3 homologue, MPXV phenotypically resembles a wild-type (wt) VACV rather than VACV-E3LΔ37N. Thus, MPXV appears to contain a gene or genes that can suppress the phenotypes associated with an N-terminal truncation in E3. The suppression maps to sequences outside F3L, suggesting that the suppression is extragenic in nature. Thus, MPXV appears to have evolved mechanisms to minimize the effects of partial inactivation of its E3 homologue.

IMPORTANCE

Poxviruses have evolved to have many mechanisms to evade host antiviral innate immunity; these mechanisms may allow these viruses to cause disease. Within the family of poxviruses, variola virus (which causes smallpox) is the most pathogenic, while monkeypox virus is intermediate in pathogenicity between vaccinia virus and variola virus. Understanding the mechanisms of monkeypox virus innate immune evasion will help us to understand the evolution of poxvirus innate immune evasion capabilities, providing a better understanding of how poxviruses cause disease.

Exploring interaction of TNF and orthopoxviral CrmB protein by surface plasmon resonance and free energy calculation

Inhibition of the activity of the tumor necrosis factor (TNF) has become the main strategy for treating inflammatory diseases. The orthopoxvirus TNF-binding proteins can bind and efficiently neutralize TNF. To analyze the mechanisms of the interaction between human (hTNF) or mouse (mTNF) TNF and the cowpox virus N-terminal binding domain (TNFBD-CPXV), also the variola virus N-terminal binding domain (TNFBD-VARV) and to define the amino acids most importantly involved in the formation of complexes, computer models, derived from the X-ray structure of a homologous hTNF/TNFRII complex, were used together with experiments. The hTNF/TNFBD-CPXV, hTNF/TNFBD-VARV, mTNF/TNFBD-CPXV, and mTNF/TNFBD-VARV complexes were used in the molecular dynamics (MD) simulations and MM/GBSA free energy calculations. The complexes were ordered as hTNF/TNFBD-CPXV, hTNF/TNFBD-VARV, mTNF/TNFBD-CPXV and mTNF/TNFBD-VARV according to increase in the binding affinity. The calculations were in agreement with surface plasmon resonance (SPR) measurements of the binding constants. Key residues involved in complex formation were identified.

Attenuation of monkeypox virus by deletion of genomic regions

Monkeypox virus (MPXV) is an emerging pathogen from Africa that causes disease similar to smallpox. Two clades with different geographic distributions and virulence have been described. Here, we utilized bioinformatic tools to identify genomic regions in MPXV containing multiple virulence genes and explored their roles in pathogenicity; two selected regions were then deleted singularly or in combination. In vitro and in vivo studies indicated that these regions play a significant role in MPXV replication, tissue spread, and mortality in mice. Interestingly, while deletion of either region led to decreased virulence in mice, one region had no effect on in vitro replication. Deletion of both regions simultaneously also reduced cell culture replication and significantly increased the attenuation in vivo over either single deletion. Attenuated MPXV with genomic deletions present a safe and efficacious tool in the study of MPX pathogenesis and in the identification of genetic factors associated with virulence.

Oncolytic virotherapy of canine and feline cancer

Cancer is the leading cause of disease-related death in companion animals such as dogs and cats. Despite recent progress in the diagnosis and treatment of advanced canine and feline cancer, overall patient treatment outcome has not been substantially improved. Virotherapy using oncolytic viruses is one promising new strategy for cancer therapy. Oncolytic viruses (OVs) preferentially infect and lyse cancer cells, without causing excessive damage to surrounding healthy tissue, and initiate tumor-specific immunity. The current review describes the use of different oncolytic viruses for cancer therapy and their application to canine and feline cancer.

Genomic variability of monkeypox virus among humans, Democratic Republic of the Congo

Monkeypox virus is a zoonotic virus endemic to Central Africa. Although active disease surveillance has assessed monkeypox disease prevalence and geographic range, information about virus diversity is lacking. We therefore assessed genome diversity of viruses in 60 samples obtained from humans with primary and secondary cases of infection from 2005 through 2007. We detected 4 distinct lineages and a deletion that resulted in gene loss in 10 (16.7%) samples and that seemed to correlate with human-to-human transmission (p = 0.0544). The data suggest a high frequency of spillover events from the pool of viruses in nonhuman animals, active selection through genomic destabilization and gene loss, and increased disease transmissibility and severity. The potential for accelerated adaptation to humans should be monitored through improved surveillance.

An increasing danger of zoonotic orthopoxvirus infections

On May 8, 1980, the World Health Assembly at its 33^rd session solemnly declared that the world and all its peoples had won freedom from smallpox and recommended ceasing the vaccination of the population against smallpox. Currently, a larger part of the world population has no immunity not only against smallpox but also against other zoonotic orthopoxvirus infections. Recently, recorded outbreaks of orthopoxvirus diseases not only of domestic animals but also of humans have become more frequent. All this indicates a new situation in the ecology and evolution of zoonotic orthopoxviruses. Analysis of state-of-the-art data on the phylogenetic relationships, ecology, and host range of orthopoxviruses—etiological agents of smallpox (variola virus, VARV), monkeypox (MPXV), cowpox (CPXV), vaccinia (VACV), and camelpox (CMLV)—as well as the patterns of their evolution suggests that a VARV-like virus could emerge in the course of natural evolution of modern zoonotic orthopoxviruses. Thus, there is an insistent need for organization of the international control over the outbreaks of zoonotic orthopoxvirus infections in various countries to provide a rapid response and prevent them from developing into epidemics.

Age- and sex-based hematological and biochemical parameters for Macaca fascicularis

Background

The cynomolgus monkey (Macaca fascicularis) has been increasingly used in biomedical research, making knowledge of its blood-based parameters essential to support the selection of healthy subjects and its use in preclinical research. As age and sex affect these blood-based parameters, it is important to establish baseline indices for these parameters on an age and sex basis and determine the effects of age and sex on these indices.

Methods

A total of 917 cynomolgus monkeys (374 males and 543 females) were selected and segregated by age (five groups) and sex. A total of 30 hematological and 22 biochemical parameters were measured, and the effects of age and sex were analyzed.

Results

Baseline indices for hematological and biochemical parameters were separately established by age and sex. Significant effects by age, sex, and age-sex interaction were observed in a number of blood parameters. In the 49–60 months and 61–72 months age groups, red blood cell count, hemoglobulin, and hematocrit showed significantly lower values (P<0.01) in females than males. Serum alkaline phosphatase varied with age in both sexes (P<0.01) and was significantly higher in females than males (P<0.05) in the groups aged 13–24 months and 25–36 months; however, in the three groups aged over 25–36 months, serum alkaline phosphatase was significantly lower in females than males (P<0.01). Creatinine concentration increased with age (P<0.01) in all age groups; specifically in the groups aged 49–60 months and 61–72 months, creatinine was significantly higher (P<0.01) in males than females. Total protein and globulin both increased with age (P<0.01).

Conclusion

The baseline values of hematological and biochemical parameters reported herein establish reference indices of blood-based parameters in the cynomolgus monkey by age and sex, thereby aiding researchers in selecting healthy subjects and evaluating preclinical studies using this species.

The inflammasome as a target of modulation by DNA viruses

The cellular innate immune response represents the initial reaction of a host against infecting pathogens. Host cells detect incoming microbes by way of a large and expanding array of receptors that react with evolutionarily conserved molecular patterns exhibited by microbial intruders. These receptors are responsible for initiating signaling that leads to both transcriptional activation of immunologically important genes as well as protease-dependent processing of cellular proteins. The inflammasome refers to a protein complex that functions as an activation platform for the cysteine protease caspase-1, which then processes inflammatory molecules such as IL-1β and IL-18 into functional forms. Assembly of this complex is triggered following receptor-mediated detection of pathogen-associated molecules. Receptors have been identified that are essential to inflammasome activation in response to numerous molecular patterns including virus-associated molecules such as DNA. In fact, the importance of cytoplasmic DNA as an immune stimulus is exemplified by the existence of at least nine distinct cellular receptors capable of initiating innate reactivity in response to this molecule. Viruses that employ DNA as genomic material include herpesviruses, poxviruses and adenoviruses. Each has been described as capable of inducing inflammasome-mediated activity. Interestingly, however, the cellular molecules responsible for these responses appear to vary according to host species, cell type and even viral strain. Secretion of IL-1β and IL-18 are important components of antimicrobial immunity and, as a result, pathogens have evolved factors to evade or counteract this response. This includes DNA-based viruses, many of which encode multiple redundant counteractive molecules. However, it is clear that such phenotypes are only beginning to be uncovered. The purpose of this review is to describe what is known regarding the activation of inflammasome-mediated processes in response to infection with well-examined families of DNA viruses and to discuss characterized mechanisms of manipulation and neutralization of inflammasome-dependent activity. This review aims to shed light on the biologically important phenomena regarding this virus-host interaction and to highlight key areas where important information is lacking.

A review of experimental and natural infections of animals with monkeypox virus between 1958 and 2012

Monkeypox virus (MPXV) was discovered in 1958 during an outbreak in an animal facility in Copenhagen, Denmark. Since its discovery, MPXV has revealed a propensity to infect and induce disease in a large number of animals within the mammalia class from pan-geographical locations. This finding has impeded the elucidation of the natural host, although the strongest candidates are African squirrels and/or other rodents. Experimentally, MPXV can infect animals via a variety of multiple different inoculation routes; however, the natural route of transmission is unknown and is likely to be somewhat species specific. In this review we have attempted to compile and discuss all published articles that describe experimental or natural infections with MPXV, dating from the initial discovery of the virus through to the year 2012. We further discuss the comparative disease courses and pathologies of the host species.