Pharmacokinetics and Efficacy of a Potential Smallpox Therapeutic, Brincidofovir, in a Lethal Monkeypox Virus Animal Model

Structural basis of human mpox viral DNA replication inhibition by brincidofovir and cidofovir

Mpox virus has wildly spread over 108 non-endemic regions in the world since May 2022. DNA replication of mpox is performed by DNA polymerase machinery F8-A22-E4, which is known as a great drug target. Brincidofovir and cidofovir are reported to have broad-spectrum antiviral activity against poxviruses, including mpox virus in animal models. However, the molecular mechanism is not understood. Here we report cryogenic electron microscopy structures of mpox viral F8-A22-E4 in complex with a DNA duplex, or dCTP and the DNA duplex, or cidofovir diphosphate and the DNA duplex at resolution of 3.22, 2.98 and 2.79 Å, respectively. Our structural work and DNA replication inhibition assays reveal that cidofovir diphosphate is located at the dCTP binding position with a different conformation to compete with dCTP to incorporate into the DNA and inhibit DNA synthesis. Conformation of both F8-A22-E4 and DNA is changed from the pre-dNTP binding state to DNA synthesizing state after dCTP or cidofovir diphosphate is bound, suggesting a coupling mechanism. This work provides the structural basis of DNA synthesis inhibition by brincidofovir and cidofovir, providing a rational strategy for new therapeutical development for mpox virus and other pox viruses.

Potential use of cidofovir, brincidofovir, and tecovirimat drugs in fighting monkeypox infection: recent trends and advancements

Recent years have witnessed the rise of more recent pandemic outbreaks including COVID-19 and monkeypox. A multinational monkeypox outbreak creates a complex situation that necessitates countermeasures to the existing quo. The first incidence of monkeypox was documented in the 1970s, and further outbreaks led to a public health emergency of international concern. Yet as of right now, neither vaccines nor medicines are certain to treat monkeypox. Even the inability of conducting human clinical trials has prevented thousands of patients from receiving effective disease management. The current state of the disease's understanding, the treatment options available, financial resources, and lastly international policies to control an epidemic state are the major obstacles to controlling epidemics. The current review focuses on the epidemiology of monkeypox, scientific ideas, and available treatments, including potential monkeypox therapeutic methods. As a result, a thorough understanding of monkeypox literature will facilitate in the development of new therapeutic medications for the prevention and treatment of monkeypox.

Brincidofovir Effectively Inhibits Proliferation of Pseudorabies Virus by Disrupting Viral Replication

Pseudorabies is an acute and febrile infectious disease caused by pseudorabies virus (PRV), a member of the family Herpesviridae. Currently, PRV is predominantly endemoepidemic and has caused significant economic losses among domestic pigs. Other animals have been proven to be susceptible to PRV, with a mortality rate of 100%. In addition, 30 human cases of PRV infection have been reported in China since 2017, and all patients have shown severe neurological symptoms and eventually died or developed various neurological sequelae. In these cases, broad-spectrum anti-herpesvirus drugs and integrated treatments were mostly applied. However, the inhibitory effect of the commonly used anti-herpesvirus drugs (e.g., acyclovir, etc.) against PRV were evaluated and found to be limited in this study. It is therefore urgent and important to develop drugs that are clinically effective against PRV infection. Here, we constructed a high-throughput method for screening antiviral drugs based on fluorescence-tagged PRV strains and multi-modal microplate readers that detect fluorescence intensity to account for virus proliferation. A total of 2104 small molecule drugs approved by the U.S. Food and Drug Administration (FDA) were studied and validated by applying this screening model, and 104 drugs providing more than 75% inhibition of fluorescence intensity were selected. Furthermore, 10 drugs that could significantly inhibit PRV proliferation in vitro were strictly identified based on their cytopathic effects, virus titer, and viral gene expression, etc. Based on the determined 50% cytotoxic concentration (CC50) and 50% inhibitory concentration (IC50), the selectivity index (SI) was calculated to be 26.3-3937.2 for these 10 drugs, indicating excellent drugability. The antiviral effects of the 10 drugs were then assessed in a mouse model. It was found that 10 mg/kg brincidofovir administered continuously for 5 days provided 100% protection in mice challenged with lethal doses of the human-origin PRV strain hSD-1/2019. Brincidofovir significantly attenuated symptoms and pathological changes in infected mice. Additionally, time-of-addition experiments confirmed that brincidofovir inhibited the proliferation of PRV mainly by interfering with the viral replication stage. Therefore, this study confirms that brincidofovir can significantly inhibit PRV both in vitro and in vivo and is expected to be an effective drug candidate for the clinical treatment of PRV infections.

Clinical considerations on monkeypox antiviral medications: An overview

Monkeypox (mpox), a virus belonging to the orthopoxvirus family, can cause a zoonotic infectious disease with morbidity and cosmetic complications. Therefore, effective antiviral drugs with appropriate safety profiles are important for the treatment of patients with mpox. To date, there is no FDA-approved drug for the treatment of mpox. However, tecovirimat, brincidofovir, and cidofovir are the candidate therapies for the management of mpox. Given the safety concerns following the use of these medications, we aimed to review evidence on the clinical considerations of mpox antiviral medications that will be useful to guide clinicians in the treatment approach. Based on the current evidence, tecovirimat has favorable clinical efficacy, safety, and side effect profile and it can be considered as first-line treatment for mpox.

Treatment and Vaccination for Smallpox and Monkeypox

The smallpox infection with the variola virus was one of the most fatal disorders until a global eradication was initiated in the twentieth century. The last cases were reported in Somalia 1977 and as a laboratory infection in the UK 1978; in 1980, the World Health Organization (WHO) declared smallpox for extinct. The smallpox virus with its very high transmissibility and mortality is still a major biothreat, because the vaccination against smallpox was stopped globally in the 1980s. For this reason, new antivirals (cidofovir, brincidofovir, and tecovirimat) and new vaccines (ACAM2000, LC16m8 and Modified Vaccine Ankara MVA) were developed. For passive immunization, vaccinia immune globulin intravenous (VIGIV) is available. Due to the relationships between orthopox viruses such as vaccinia, variola, mpox (monkeypox), cowpox, and horsepox, the vaccines (LC16m8 and MVA) and antivirals (brincidofovir and tecovirimat) could also be used in the mpox outbreak with positive preliminary data. As mutations can result in drug resistance against cidofovir or tecovirimat, there is need for further research. Further antivirals (NIOCH-14 and ST-357) and vaccines (VACΔ6 and TNX-801) are being developed in Russia and the USA. In conclusion, further research for treatment and prevention of orthopox infections is needed and is already in progress. After a brief introduction, this chapter presents the smallpox and mpox disease and thereafter full overviews on antiviral treatment and vaccination including the passive immunization with vaccinia immunoglobulins.

Identification of In Vitro Inhibitors of Monkeypox Replication

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

Monkeypox Virus: A Comprehensive Overview of Viral Pathology, Immune Response, and Antiviral Strategies

BACKGROUND

The years 2022-2023 witnessed a monkeypox virus (mpox) outbreak in some countries worldwide, where it exists in an endemic form. However, the number of infectious cases is continuously on the rise, and there has been an unexpected, drastic increase in cases that result from sustained transmission in non-endemic regions of the world. Under this scenario, it is pertinent for the world to be aware of healthcare threats to mpox infection. This review aimed to compile advanced data regarding the different aspects of mpox disease.

METHODS

A comprehensive strategy for the compilation of recent data was adopted to add data regarding mpox, biology, viral pathology, immune response, and brief details on the antiviral strategies under trial; the search was limited to 2016-2023. The aim is to make the scientific community aware of diverse aspects of mpox.

RESULTS

Consequently, detailed insights have been drawn with regard to the nature, epidemiology, etiology, and biological nature of mpox. Additionally, its host interaction and viral infectious cycle and immune interventions have been briefly elaborated. This comprehensively drawn literature review delivers brief insights into the biological nature, immune responses, and clinical developments in the form of therapeutics against mpox. This study will help scientists understand the biological nature and responses in hosts, which will further help clinicians with therapeutic handling, diagnosis, and treatment options.

CONCLUSIONS

This study will provide updated information on mpox's pathology, immune responses, and antiviral strategies. Moreover, it will also help the public to become educated on the healthcare-associated threat and take timely mitigation measures against expected mpox outbreaks in the future.

A Narrative Review on the Monkeypox Virus: An Ongoing Global Outbreak Hitting the Non-Endemic Countries

Monkeypox is a rare zoonotic DNA with lineage from the Poxviridae family, Chordopoxvirinae subfamily, and Orthopoxvirus genus. With a previous history of controlled and contained occasional outbreaks of the virus, currently, a widely erupted outbreak of monkeypox with progressively rising numbers has been reported since May 2022 in multiple countries of the western hemisphere that are not historically endemic for this infection, particularly the United Kingdom and European Union countries. We have written a comprehensive review article to help clinicians better understand the disease. The global cessation of smallpox vaccination has been hypothesized to cause the rise in monkeypox infections in recent years. Monkeypox, like any other viral infection, commences with prodromal symptoms; a maculopapular rash with centrifugal distribution usually follows. Polymerase chain reaction (PCR) confirms the diagnosis. Transmission in humans is possible through infected animals or humans. In the ongoing 2022 outbreak, the monkeypox virus has been undergoing novel mutations at an alarming rate. Treatment options for monkeypox are an area that still requires extensive research, and the utility of certain antiviral medications in treating monkeypox infection is currently being explored but is still controversial and debatable.

Human Monkeypox: A Comprehensive Overview of Epidemiology, Pathogenesis, Diagnosis, Treatment, and Prevention Strategies

Monkeypox virus (MPXV) is an emerging zoonotic virus that belongs to the Orthopoxvirus genus and presents clinical symptoms similar to those of smallpox, such as fever and vesicular-pustular skin lesions. However, the differential diagnosis between smallpox and monkeypox is that smallpox does not cause lymphadenopathy but monkeypox generates swelling in the lymph nodes. Since the eradication of smallpox, MPXV has been identified as the most common Orthopoxvirus to cause human disease. Despite MPXV being endemic to certain regions of Africa, the current MPXV outbreak, which began in early 2022, has spread to numerous countries worldwide, raising global concern. As of the end of May 2023, over 87,545 cases and 141 deaths have been reported, with most cases identified in non-endemic countries, primarily due to human-to-human transmission. To better understand this emerging threat, this review presents an overview of key aspects of MPXV infection, including its animal reservoirs, modes of transmission, animal models, epidemiology, clinical and immunological features, diagnosis, treatments, vaccines, and prevention strategies. The material presented here provides a comprehensive understanding of MPXV as a disease, while emphasizing the significance and unique characteristics of the 2022 outbreak. This offers valuable information that can inform future research and aid in the development of effective interventions.

Clinical Strategies and Therapeutics for Human Monkeypox Virus: A Revised Perspective on Recent Outbreaks

An enveloped double-stranded DNA monkeypox virus (MPXV) is a causative agent of the zoonotic viral disease, human monkeypox (HMPX). MPXV belongs to the genus Orthopoxviridae, a family of notorious smallpox viruses, and so it shares similar clinical pathophysiological features. The recent multicountry HMPX outbreak (May 2022 onwards) is recognized as an emerging global public health emergency by the World Health Organization, shunting its endemic status as opined over the past few decades. Re-emergence of HMPX raises concern to reassess the present clinical strategy and therapeutics as its outbreak evolves further. Keeping a check on these developments, here we provide insights into the HMPX epidemiology, pathophysiology, and clinical representation. Weighing on its early prevention, we reviewed the strategies that are being enrolled for HMPX diagnosis. In the line of expanded MPXV prevalence, we further reviewed its clinical management and the diverse employed preventive/therapeutic strategies, including vaccines (JYNNEOS, ACAM2000, VIGIV) and antiviral drugs/inhibitors (Tecovirimat, Cidofovir, Brincidofovir). Taken together, with a revised perspective of HMPX re-emergence, the present report summarizes new knowledge on its prevalence, pathology, and prevention strategies.

Clinical and Translational Pharmacology Considerations for Anti-infectives Approved Under the FDA Animal Rule

The US Food and Drug Administration's Animal Rule provides a pathway for approval of drugs and biologics aimed to treat serious or life-threatening conditions wherein traditional clinical trials are either not ethical or feasible. In such a scenario, determination of safety and efficacy are based on integration of data on drug disposition and drug action collected from in vitro models, infected animals, and healthy volunteer human studies. The demonstration of clinical efficacy and safety in humans based on robust, well-controlled animal studies is filled with challenges. This review elaborates on the challenges in the translation of data from in vitro and animal models to human dosing for antimicrobials. In this context, it discusses precedents of drugs approved under the Animal Rule, along with the approaches and guidance undertaken by sponsors.

A systematic review to identify novel clinical characteristics of monkeypox virus infection and therapeutic and preventive strategies to combat the virus

Since May 2022, there has been a global increase in the number of Mpox virus (MPXV) cases in countries that were previously considered non-endemic. In July 2022, the World Health Organization (WHO) declared this outbreak a public health emergency of international concern. The objective of this systematic review is to examine the novel clinical features of Mpox and to assess the available treatment options for managing the disease in patients who are afflicted with it. We conducted a systematic search in several databases, including PubMed, Google Scholar, Cochrane Library, and the grey literature, from May 2022 to February 2023. We identified 21 eligible studies, which included 18,275 Mpox cases, for final qualitative analysis. The majority of cases were reported in men who have sex with men (MSM) and immunocompromised individuals with HIV (36.1%). The median incubation period was 7 days (IQR: 3-21). The novel clinical manifestations include severe skin lesions on the palms, oral and anogenital regions, as well as proctitis, penile edema, tonsillitis, ocular disease, myalgia, lethargy, and sore throat, without any preceding prodromal symptoms or systemic illness. In addition, fully asymptomatic cases were documented, and various complications, including encephalomyelitis and angina, were noted. Clinicians must be familiar with these novel clinical characteristics, as they can aid in testing and tracing such patients, as well as asymptomatic high-risk populations such as heterosexuals and MSM. In addition to supportive care, currently, there are several effective prophylactic and treatment strategies available to combat Mpox, including the vaccines ACAM2000 and MVA-BN7, as well as the immunoglobulin VIGIV and the antivirals tecovirimat, brincidofovir, and cidofovir against severe Mpox infection.

The Global Monkeypox (Mpox) Outbreak: A Comprehensive Review

Monkeypox (Mpox) is a contagious illness that is caused by the monkeypox virus, which is part of the same family of viruses as variola, vaccinia, and cowpox. It was first detected in the Democratic Republic of the Congo in 1970 and has since caused sporadic cases and outbreaks in a few countries in West and Central Africa. In July 2022, the World Health Organization (WHO) declared a public-health emergency of international concern due to the unprecedented global spread of the disease. Despite breakthroughs in medical treatments, vaccines, and diagnostics, diseases like monkeypox still cause death and suffering around the world and have a heavy economic impact. The 85,189 reported cases of Mpox as of 29 January 2023 have raised alarm bells. Vaccines for the vaccinia virus can protect against monkeypox, but these immunizations were stopped after smallpox was eradicated. There are, however, treatments available once the illness has taken hold. During the 2022 outbreak, most cases occurred among men who had sex with men, and there was a range of 7-10 days between exposure and the onset of symptoms. Three vaccines are currently used against the Monkeypox virus. Two of these vaccines were initially developed for smallpox, and the third is specifically designed for biological-terrorism protection. The first vaccine is an attenuated, nonreplicating smallpox vaccine that can also be used for immunocompromised individuals, marketed under different names in different regions. The second vaccine, ACAM2000, is a recombinant second-generation vaccine initially developed for smallpox. It is recommended for use in preventing monkeypox infection but is not recommended for individuals with certain health conditions or during pregnancy. The third vaccine, LC16m8, is a licensed attenuated smallpox vaccine designed to lack the B5R envelope-protein gene to reduce neurotoxicity. It generates neutralizing antibodies to multiple poxviruses and broad T-cell responses. The immune response takes 14 days after the second dose of the first two vaccines and 4 weeks after the ACAM2000 dose for maximal immunity development. The efficacy of these vaccines in the current outbreak of monkeypox is uncertain. Adverse events have been reported, and a next generation of safer and specific vaccines is needed. Although some experts claim that developing vaccines with a large spectrum of specificity can be advantageous, epitope-focused immunogens are often more effective in enhancing neutralization.

Monkeypox: A New Challenge for Global Health System?

The COVID-19 pandemic, starting in 2020, has presented a major challenge in terms of early diagnosis and the subsequent containment and management of severe cases. The spread of viruses such as monkeypox in non-endemic countries is now creating new difficulties for healthcare professionals. Proper case definition and clinical examination are crucial for the early identification of suspected cases. For this reason, we performed a review of the literature in order to report the first signs, which are useful for healthcare providers for early case identification. Since 2022 to date, 86,930 laboratory-confirmed cases and 1051 probable cases have been reported worldwide, and of these, 116 were fatal cases and, for the first time, most of the cases were registered in countries that have not historically reported monkeypox and that lack direct or immediate epidemiological links to areas of West or Central Africa where the disease is endemic. Patients with Monkeypox experience prodromal symptoms, such as fever, fatigue, headache, muscle aches, and a rash after an incubation period of 5-21 days. The disease is usually self-limiting within 2-4 weeks but can lead to complications, such as pneumonia, encephalitis, kidney injury, and myocarditis in children, pregnant individuals, and those with weakened immune systems. The case-fatality ratio is between 1 and 10%. Today, prevention campaigns and the control of human monkeypox are the best weapons to prevent infection and stop transmission. Prevention strategies, such as avoiding contact with sick or dead animals, and the proper preparation of all foods containing animal meat or parts, should be adopted. Furthermore, close contact with infected people or contaminated materials should be avoided to prevent human-to-human transmission.

Monkeypox: a review of epidemiological modelling studies and how modelling has led to mechanistic insight

Human monkeypox (mpox) virus is a viral zoonosis that belongs to the Orthopoxvirus genus of the Poxviridae family, which presents with similar symptoms as those seen in human smallpox patients. Mpox is an increasing concern globally, with over 80,000 cases in non-endemic countries as of December 2022. In this review, we provide a brief history and ecology of mpox, its basic virology, and the key differences in mpox viral fitness traits before and after 2022. We summarize and critique current knowledge from epidemiological mathematical models, within-host models, and between-host transmission models using the One Health approach, where we distinguish between models that focus on immunity from vaccination, geography, climatic variables, as well as animal models. We report various epidemiological parameters, such as the reproduction number, R0, in a condensed format to facilitate comparison between studies. We focus on how mathematical modelling studies have led to novel mechanistic insight into mpox transmission and pathogenesis. As mpox is predicted to lead to further infection peaks in many historically non-endemic countries, mathematical modelling studies of mpox can provide rapid actionable insights into viral dynamics to guide public health measures and mitigation strategies.

Antivirals against monkeypox infections

Monkeypox virus (MPXV) infection in humans are historically restricted to endemic regions in Africa. However, in 2022, an alarming number of MPXV cases have been reported globally with evidence of person-to-person transmission. Because of this, the World Health Organization (WHO) declared the MPXV outbreak a public health emergency of international concern. MPXV vaccines are limited and only two antivirals, tecovirimat and brincidofovir, approved by the United States (US) Food and Drug Administration (FDA) for the treatment of smallpox, are currently available for the treatment of MPXV infection. Here, we evaluated 19 compounds previously shown to inhibit different RNA viruses for their ability to inhibit Orthopoxvirus infections. We first used recombinant vaccinia virus (rVACV) expressing fluorescence (Scarlet or GFP) and luciferase (Nluc) reporter genes to identify compounds with anti-Orthopoxvirus activity. Seven compounds from the ReFRAME library (antimycin A, mycophenolic acid, AVN- 944, pyrazofurin, mycophenolate mofetil, azaribine, and brequinar) and six compounds from the NPC library (buparvaquone, valinomycin, narasin, monensin, rotenone, and mubritinib) showed antiviral activity against rVACV. Notably, the anti-VACV activity of some of the compounds in the ReFRAME library (antimycin A, mycophenolic acid, AVN- 944, mycophenolate mofetil, and brequinar) and all the compounds from the NPC library (buparvaquone, valinomycin, narasin, monensin, rotenone, and mubritinib) were confirmed with MPXV, demonstrating the broad-spectrum antiviral activity against Orthopoxviruses and their potential to be used for the antiviral treatment of MPXV, or other Orthopoxvirus, infections.

IMPORTANCE

Despite the eradication of smallpox, some Orthopoxviruses remain important human pathogens, as exemplified by the recent 2022 monkeypox virus (MPXV) outbreak. Although smallpox vaccines are effective against MPXV, there is presently limited access to those vaccines. In addition, current antiviral treatment against MPXV infections is limited to the use of the FDA-approved drugs tecovirimat and brincidofovir. Thus, there is an urgent need to identify novel antivirals for the treatment of MPXV, and other potentially zoonotic Orthopoxvirus infections. Here, we show that thirteen compounds, derived from two different libraries, previously found to inhibit several RNA viruses, exhibit also antiviral activity against VACV. Notably, eleven compounds also displayed antiviral activity against MPXV, demonstrating their potential to be incorporated into the therapeutic armamentarium to combat Orthopoxvirus infections.

Recent Advances in Research and Management of Human Monkeypox Virus: An Emerging Global Health Threat

In 2003, the United States saw an epidemic of monkeypox that was later traced back to rodents of West Africa infected with the monkeypox virus (MPXV). Disease in the United States seemed less severe than the smallpox-like disease in the Democratic Republic of the Congo (DRC). In this study, researchers analyzed data from Central Africa: two distinct MPXV clades were confirmed by sequencing the genomes of MPXV isolates from Western Africa, the United States, and Central Africa. By comparing open reading frames across MPXV clades, scientists can infer which virus proteins might account for the observed variation in pathogenicity in humans. Monkeypox can be prevented and controlled with a better understanding of MPXV's molecular etiology and epidemiological and clinical features. In light of the current outbreaks worldwide, we provide updated information on monkeypox for medical professionals in this review.

Identification and Investigation of a Cryptic Binding Pocket of the P37 Envelope Protein of Monkeypox Virus by Molecular Dynamics Simulations

The spread of the monkeypox virus has surged during the unchecked COVID-19 epidemic. The most crucial target is the viral envelope protein, p37. However, lacking p37's crystal structure is a significant hurdle to rapid therapeutic discovery and mechanism elucidation. Structural modeling and molecular dynamics (MD) of the enzyme with inhibitors reveal a cryptic pocket occluded in the unbound structure. For the first time, the inhibitor's dynamic flip from the active to the cryptic site enlightens p37's allosteric site, which squeezes the active site, impairing its function. A large force is needed for inhibitor dissociation from the allosteric site, ushering in its biological importance. In addition, hot spot residues identified at both locations and discovered drugs more potent than tecovirimat may enable even more robust inhibitor designs against p37 and accelerate the development of monkeypox therapies.

Monkeypox Virus in Animals: Current Knowledge of Viral Transmission and Pathogenesis in Wild Animal Reservoirs and Captive Animal Models

Mpox, formerly called monkeypox, is now the most serious orthopoxvirus (OPXV) infection in humans. This zoonotic disease has been gradually re-emerging in humans with an increasing frequency of cases found in endemic areas, as well as an escalating frequency and size of epidemics outside of endemic areas in Africa. Currently, the largest known mpox epidemic is spreading throughout the world, with over 85,650 cases to date, mostly in Europe and North America. These increased endemic cases and epidemics are likely driven primarily by decreasing global immunity to OPXVs, along with other possible causes. The current unprecedented global outbreak of mpox has demonstrated higher numbers of human cases and greater human-to-human transmission than previously documented, necessitating an urgent need to better understand this disease in humans and animals. Monkeypox virus (MPXV) infections in animals, both naturally occurring and experimental, have provided critical information about the routes of transmission; the viral pathogenicity factors; the methods of control, such as vaccination and antivirals; the disease ecology in reservoir host species; and the conservation impacts on wildlife species. This review briefly described the epidemiology and transmission of MPXV between animals and humans and summarizes past studies on the ecology of MPXV in wild animals and experimental studies in captive animal models, with a focus on how animal infections have informed knowledge concerning various aspects of this pathogen. Knowledge gaps were highlighted in areas where future research, both in captive and free-ranging animals, could inform efforts to understand and control this disease in both humans and animals.

An overview on monkeypox virus: Pathogenesis, transmission, host interaction and therapeutics

Orthopoxvirus is one of the most notorious genus amongst the Poxviridae family. Monkeypox (MP) is a zoonotic disease that has been spreading throughout Africa. The spread is global, and incidence rates are increasing daily. The spread of the virus is rapid due to human-to-human and animals-to-human transmission. World Health Organization (WHO) has declared monkeypox virus (MPV) as a global health emergency. Since treatment options are limited, it is essential to know the modes of transmission and symptoms to stop disease spread. The information from host-virus interactions revealed significantly expressed genes that are important for the progression of the MP infection. In this review, we highlighted the MP virus structure, transmission modes, and available therapeutic options. Furthermore, this review provides insights for the scientific community to extend their research work in this field.

Diagnosis, treatment, and prevention of monkeypox in children: an experts' consensus statement

Monkeypox is a zoonotic disease. Since the first human monkeypox case was detected in 1970, it has been prevalent in some countries in central and western Africa. Since May 2022, monkeypox cases have been reported in more than 96 non-endemic countries and regions worldwide. As of September 14, 2022, there have been more than 58,200 human monkeypox cases, and there is community transmission. The cessation of smallpox vaccination in 1980, which had some cross-protection with monkeypox, resulted in a general lack of immunity to monkeypox, which caused global concern and vigilance. As of September 14, 2022, there are four monkeypox cases in China, including three in Taiwan province and one in Hong Kong city. Previous foreign studies have shown that children are vulnerable to monkeypox and are also at high risk for severe disease or complications. In order to improve pediatricians' understanding of monkeypox and achieve early detection, early diagnosis, early treatment,  and early disposal, we have organized national authoritative experts in pediatric infection, respiratory, dermatology, critical care medicine, infectious diseases, and public health and others to formulate this expert consensus, on the basis of the latest "Clinical management and infection prevention and control for monkeypox" released by The World Health Organization, the "guidelines for diagnosis and treatment of monkeypox (version 2022)" issued by National Health Commission of the People's Republic of China and other relevant documents. During the development of this consensus, multidisciplinary experts have repeatedly demonstrated the etiology, epidemiology, transmission, clinical manifestations, laboratory examinations, diagnosis, differential diagnosis, treatment, discharge criteria, prevention, disposal process, and key points of prevention and control of suspected and confirmed cases.

Monkeypox virus: past and present

BACKGROUND

The objective of this paper is to analyze the current status of monkeypox worldwide. In the face of this public health threat, our purpose is to elucidate the clinical characteristics and epidemiology of monkeypox, the developmental progress of monkeypox-related drugs and the vaccines available.

DATA SOURCES

The literature review was performed in databases including PubMed, Science Direct and Google Scholar up to July 2022.

RESULTS

Since May 2022, the World Health Organization has reported more than 45,000 confirmed cases from 92 nonendemic countries, including nine deaths. Although some women and children have been infected so far, most cases have occurred among men who have sex with other men, especially those with multiple sexual partners or anonymous sex.

CONCLUSIONS

Pediatric monkeypox infection has been associated with a higher likelihood of severe illness and mortality than in adults. Severe monkeypox illness in pediatrics often requires adjunctive antiviral therapy. It is crucial for all countries to establish sound monitoring and testing systems and be prepared with emergency preparedness.

Recent Developments in Mpox Prevention and Treatment Options

Human mpox is an emerging epidemic in the world. The monkey pox virus (MPXV) belongs to the same family of zoonotic Orthopoxviridae as that of the smallpox virus and exhibits similar clinical symptomology. Information regarding its diagnostics, disease epidemiology, surveillance, preventive methods, and treatment strategies are being collated with time. The purpose of this review is to trace the recent events in the scientific platform that have defined new preventive and treatment strategies against mpox. A methodological approach has been used to gather data from the latest literature to comprehensively overview the emerging treatment options. The results portion will cover details regarding the prevention of mpox. It will also shed light on a brief description of contemporary vaccines and antiviral agents that have been evaluated for their treatment potential since the emergence of the mpox threat. These treatment options are setting the pace for controlling the widespread monkeypox infection. However, the limitations attached to these treatment strategies need to be tackled quickly to increase their efficacy so that they can be deployed on a large scale for the prevention of this epidemic becoming another pandemic in this decade.

Use of cidofovir in a patient with severe mpox and uncontrolled HIV infection

A 48-year-old man with poorly controlled HIV presented with severe human monkeypox virus (hMPXV) infection, having completed 2 weeks of tecovirimat at another hospital. He had painful, ulcerating skin lesions on most of his body and oropharyngeal cavity, with subsequent Ludwig's angina requiring repeated surgical interventions. Despite commencing a second, prolonged course of tecovirimat, he did not objectively improve, and new lesions were still noted at day 24. Discussion at the UK National Health Service England High Consequence Infectious Diseases Network recommended the use of 3% topical and then intravenous cidofovir, which was given at 5 mg/kg; the patient made a noticeable improvement after the first intravenous dose. He received further intravenous doses at 7 days and 21 days after the dose and was discharged at day 52. Cidofovir is not licensed for use in treatment of hMPXV infection. Data for cidofovir use in hMPXV are restricted to studies in animals. Four other documented cases of cidofovir use against hMPXV have been reported in the USA in 2022, but we present its first use in the UK. The scarcity of studies into the use of cidofovir in this condition clearly shows the need for robust studies to assess efficacy, optimum dosage, timing, and route of administration.

Insights into the Novel Therapeutics and Vaccines against Herpes Simplex Virus

Herpes simplex virus (HSV) is a great concern of the global health community due to its linked infection of inconspicuous nature and resultant serious medical consequences. Seropositive patients may develop ocular disease or genital herpes as characteristic infectious outcomes. Moreover, the infectious nature of HSV is so complex that the available therapeutic options have been modified in certain ways to cure it. However, no permanent and highly effective cure has been discovered. This review generates insights into the available prophylactic and therapeutic interventions against HSV. A methodological research approach is used for study design and data complication. Only the latest data from publications are acquired to shed light on updated therapeutic approaches. These studies indicate that the current antiviral therapeutics can suppress the symptoms and control viral transmission up to a certain level, but cannot eradicate the natural HSV infection and latency outcomes. Most trials that have entered the clinical phase are made part of this review to understand what is new within the field. Some vaccination approaches are also discussed. Moreover, some novel therapeutic options that are currently in research annals are given due consideration for future development. The data can enable the scientific community to direct their efforts to fill the gaps that remain unfilled in terms of therapies for HSV. The need is to integrate scientific efforts to produce a proper cure against HSV to control the virus spread, resistance, and mutation in future disease management.

Oral Brincidofovir Therapy for Monkeypox Outbreak: A Focused Review on the Therapeutic Potential, Clinical Studies, Patent Literature, and Prospects

The monkeypox disease (MPX) outbreak of 2022 has been reported in more than one hundred countries and is becoming a global concern. Unfortunately, only a few treatments, such as tecovirimat (TCV), are available against MPX. Brincidofovir (BCV) is a United States Food and Drug Administration (USFDA)-approved antiviral against smallpox. This article reviews the potential of BCV for treating MPX and other Orthopoxvirus (OPXVs) diseases. The literature for this review was collected from PubMed, authentic websites (USFDA, Chimerix), and freely available patent databases (USPTO, Espacenet, and Patentscope). BCV (a lipophilic derivative of cidofovir) has been discovered and developed by Chimerix Incorporation, USA. Besides smallpox, BCV has also been tested clinically for various viral infections (adenovirus, cytomegalovirus, ebola virus, herpes simplex virus, and double-stranded DNA virus). Many health agencies and reports have recommended using BCV for MPX. However, no health agency has yet approved BCV for MPX. Accordingly, the off-label use of BCV is anticipated for MPX and various viral diseases. The patent literature revealed some important antiviral compositions of BCV. The authors believe there is a huge opportunity to create novel, inventive, and patentable BCV-based antiviral therapies (new combinations with existing antivirals) for OPXVs illnesses (MPX, smallpox, cowpox, camelpox, and vaccinia). It is also advised to conduct drug interaction (food, drug, and disease interaction) and drug resistance investigations on BCV while developing its combinations with other medications. The BCV-based drug repurposing options are also open for further exploration. BCV offers a promising opportunity for biosecurity against OPXV-based bioterrorism attacks and to control the MPX outbreak of 2022.

Current Insights into Diagnosis, Prevention Strategies, Treatment, Therapeutic Targets, and Challenges of Monkeypox (Mpox) Infections in Human Populations

In the wake of the emergence and worldwide respread of a viral infection called Monkeypox (Mpox), there is a serious threat to the health and safety of the global population. This viral infection was endemic to the western and central parts of Africa, but has recently spread out of this endemic area to various countries, including the United Kingdom (UK), Portugal, Spain, the United States of America (USA), Canada, Sweden, Belgium, Italy, Australia, Germany, France, the Netherlands, Israel, and Mexico. This is a timely review focusing on recent findings and developments in the epidemiology, clinical features, therapeutic targets, diagnosis, prevention mechanisms, research challenges and possible treatment for Mpox. To date (29 November 2022), there have been around 81,225 reported cases of Mpox. In most cases, this illness is mild; however, there is a fatality rate ranging from 1 to 10%, which might be increased due to associated complications and/or secondary infections. There is a real challenge in the diagnosis of Mpox, since its symptoms are very similar to those of other infections, including smallpox and chickenpox. Generally, to prevent/limit the risk and transmission of Mpox, the detection and isolation of infected individuals, as well as hand hygiene and cleanliness, are essential and effective approaches to control/combat this viral infection. Nevertheless, updated information about Mpox from different angles is lacking. Thus, this review provides updated and comprehensive information about the Mpox illness, which should highlight the global burden, pathogenicity, symptoms, diagnosis, prevention measures and possible treatment of this emerging disease.

Monkeypox 2022 Outbreak: How Alarming Is the Situation? Epidemiological and Clinical Review

Monkeypox is a disease caused by Orthopoxvirus, which also includes the smallpox virus. Several endemics have been reported on the African continent, typically in the western and central regions. However, since 13 May 2022, there have been several cases reported from different member states; the number of confirmed cases in 1 month exceeded the total number of cases reported outside the African continent since the first case in 1970. The World Health Organization (WHO) and Centers for Disease Control (CDC) consider monkeypox as an important disease for global public health. The clinical manifestations and laboratory findings in patients with monkeypox remain unclear. In this brief review, we investigated and compared the different characteristics already reported in cases of monkeypox.

Monkeypox treatment: Current evidence and future perspectives

As of September 11, 2022, 57 669 reports of monkeypox infection raised global concern. Previous vaccinia virus vaccination can protect from monkeypox. However, after smallpox eradication, immunization against that was stopped. Indeed, therapeutic options following the disease onset are of great value. This study aimed to review the available evidence on virology and treatment approaches for monkeypox and provide guidance for patient care and future studies. Since no randomized clinical trials were ever performed, we reviewed monkeypox animal model studies and clinical trials on the safety and pharmacokinetics of available medications. Brincidofovir and tecovirimat were the most studied medications that got approval for smallpox treatment according to the Animal Rule. Due to the conserved virology among Orthopoxviruses, available medications might also be effective against monkeypox. However, tecovirimat has the strongest evidence to be effective and safe for monkeypox treatment, and if there is a choice between the two drugs, tecovirimat has shown more promise so far. The risk of resistance should be considered in patients who failed to respond to tecovirimat. Hence, the target-based design of novel antivirals will enhance the availability and spectrum of effective anti-Orthopoxvirus agents.

Recent Advances in the Prevention and Management of Monkeypox Viral Infection in Humans

BACKGROUND

There have been several neglected infectious pathogens that have reemerged in the last few decades, including the monkeypox virus, a virus from the orthopoxviral genus that causes monkeypox and is transmitted between animals and humans. The human monkeypox outbreak has spread to several different countries. Because of the outbreak's unusually high case count and lack of connections to endemic nations, there are concerns that the monkeypox transmission pattern may have changed.

OBJECTIVE

The current study aimed to provide recent advancements in the prevention and management of the monkeypox virus in humans.

METHODOLOGY

We have highlighted recent advancements in the prevention and management of the monkeypox virus in humans in this work.

RESULTS

For the treatment and prevention of monkeypox, new medications and vaccinations are being used, and more study is needed to understand the epidemiology, biology, and ecology of the virus in endemic regions and stop future global outbreaks. Vaccines available in the market for the treatment of viruses are JYNEOS and ACAM2000. Some of the antiviral drugs, such as tecovirimat, brincidofovir, cidofovir, trifluridine, and vaccinia immune globulin, are used for the treatment of the monkeypox virus. Some of the vaccines, such as NIOCH-14, Cidofovir, CMX-001, and ST-246, are currently in clinical trials.

CONCLUSION

We have, herein, covered features of monkeypox viral biology that are important for risk assessment and getting ready for an outbreak of the monkeypox virus, with a focus on recent advances in knowledge of the virus's host range, evolutionary potential, and potential targets for neutralization.

Monkeypox Virus Infections in Humans

Human monkeypox is a viral zoonosis endemic to West and Central Africa that has recently generated increased interest and concern on a global scale as an emerging infectious disease threat in the midst of the slowly relenting COVID-2019 disease pandemic. The hallmark of infection is the development of a flu-like prodrome followed by the appearance of a smallpox-like exanthem. Precipitous person-to-person transmission of the virus among residents of 100 countries where it is nonendemic has motivated the immediate and widespread implementation of public health countermeasures. In this review, we discuss the origins and virology of monkeypox virus, its link with smallpox eradication, its record of causing outbreaks of human disease in regions where it is endemic in wildlife, its association with outbreaks in areas where it is nonendemic, the clinical manifestations of disease, laboratory diagnostic methods, case management, public health interventions, and future directions.

Chain-Engineering-Based De Novo Drug Design against MPXVgp169 Virulent Protein of Monkeypox Virus: A Molecular Modification Approach

The unexpected appearance of the monkeypox virus and the extensive geographic dispersal of cases have prompted researchers to concentrate on potential therapeutic approaches. In addition to its vaccine build techniques, there should be some multiple integrated antiviral active compounds because of the MPV (monkeypox virus) outbreak in 2022. This study offers a computational engineering-based de novo drug discovery mediated by random antiviral active compounds that were screened against the virulent protein MPXVgp169, as one of the key players directing the pathogenesis of the virus. The screening of these candidates was supported by the use of 72 antiviral active compounds. The top candidate with the lowest binding affinity was selected for the engineering of chains or atoms. Literature assisted to identify toxic chains or atoms that were impeding the stability and effectiveness of antiviral compounds to modify them for enhanced efficacy. With a binding affinity of -9.4 Kcal/mol after chain, the lipophilicity of 0.41, the water solubility of 2.51 as soluble, and synthetic accessibility of 6.6, chain-engineered dolutegravir was one of the best active compounds, as proved by the computational engineering analysis. This study will revolutionize the era of drug engineering as a potential therapeutic strategy for monkeypox infection.

The Potential Role of Passive Antibody-Based Therapies as Treatments for Monkeypox

Monkeypox, a zoonosis caused by the orthopox monkeypox virus (MPXV) that is endemic to Central and West Africa, was previously linked to sporadic outbreaks and rare, travel-associated cases. An outbreak of monkeypox in 2022 has spurred a public health emergency of international concern, and this outbreak is unprecedented in terms of its scale and epidemiology. The outbreak has been focused overwhelmingly in men who have sex with men; however, the trajectory of the outbreak remains uncertain, with spread now being reported in women and children. The mortality has been low (<1%), yet the morbidity is high. Vaccines and oral antiviral agents that have been developed to protect against smallpox are available for use against monkeypox. However, the supply has been unable to match the demand during the outbreak. Passive antibody-based therapies, such as hyperimmune globulin (HIG), monoclonal antibodies, and convalescent plasma (CP), have been used against a diverse array of infectious diseases, culminating in their extensive use during the COVID-19 pandemic. Passive antibody-based therapies could play a role in the treatment of monkeypox, either as a temporizing role amid a shortfall in vaccines and antivirals or a complementary role to direct-acting antivirals. Drawing on the collective experience to date, there are regulatory, administrative, and logistical challenges to the implementation of antibody-based therapies. Their efficacy is contingent upon early administration and the presence of high-titer antibodies against the targeted pathogen. Research is needed to address questions pertaining to how to qualify HIG and CP and to determine their relative efficacy against MPXV, compared to antecedent therapies and preventative strategies. IMPORTANCE Monkeypox is an infection caused by the monkeypox virus (MPXV). The clinical findings in monkeypox include fever and rash. Historically, most cases of human monkeypox were reported in Africa. This changed in 2022, with a massive escalation in the number of cases across multiple countries, mainly affecting men who have sex with men. Although vaccines and oral antiviral medications are available for the treatment of monkeypox, their supply has been overwhelmed by the unprecedented number of cases. Antibody-based therapies (ABTs) have long been used to treat infectious diseases. They are produced in a laboratory or from plasma that has been collected from individuals who have recovered from an infection or have been vaccinated against that infection (in this case, monkeypox). ABTs could play a role in the treatment of monkeypox, either while awaiting oral medications or as a complementary treatment for patients that are at risk of severe disease.

Therapeutic strategies for human poxvirus infections: Monkeypox (mpox), smallpox, molluscipox, and orf

Therapeutic and vaccine development for human poxvirus infections (e.g., monkeypox (mpox) virus, variola virus, molluscum contagiosum virus, orf virus) has been largely deserted, especially after the eradication of smallpox by 1980. Human mpox is a self-limited disease confined to Central and West Africa for decades. However, since April 2022, mpox has quickly emerged as a multi-country outbreak, urgently calling for effective antiviral agents and vaccines to control mpox. Here, this review highlights possible therapeutic options (e.g., tecovirimat, brincidofovir, cidofovir) and other strategies (e.g., vaccines, intravenous vaccinia immune globulin) for the management of human poxvirus infections worldwide.

Monkeypox in humans: a new outbreak

Infection caused by Monkeypox Virus (MPVX) has small rodents as its natural reservoir and both monkeys and humans are occasional hosts. The causative agent is an Orthopoxvirus (MPVX) that was isolated in monkeys in 1958 and proved capable of passing to humans in 1970. It remained contained in Africa, causing isolated episodes of infection, until 2003 when an outbreak occurred in the United States following importation of animals from that continent. Since then, anecdotal cases have continued to be reported outside Africa, usually very clearly linked to travelers to those countries, but in May 2022, a broad outbreak of this disease has begun, now affecting several continents, with the emergence of human cases of MPVX (H-MPVX) infection mainly among Men that have Sex with Men (MSM). The disease has an incubation time ranging from 5 to 15 days and is characterized by the presence of pustules, fever, malaise and headache. The presence of significant regional lymphadenopathy is a differential feature with episodes of classical smallpox. Proctitis and pharyngitis, with minimal skin lesions, may be another form of presentation. Diagnosis can be confirmed by PCR testing of lesions or by demonstration of MPVX in other body fluids or tissues, although in the appropriate epidemiologic setting the clinical picture is highly suggestive of the disease. Effective drug treatment has been developed as part of programs to protect against potential bioterrorist agents and smallpox vaccinees are known to have high protection against monkeypox. New vaccines are available, but neither the drugs nor the vaccines are yet freely available on the market. The prognosis of the disease appears, at least in adults in developed countries, to be good, with very low mortality figures and much less aggressive behavior than that described in classical smallpox. Isolation measures, essential for the control of the outbreak, have been published by the health authorities.

Outbreaks of human monkeypox during the COVID-19 pandemic: a systematic review for healthcare professionals

The ongoing 2022 multicountry monkeypox epidemic has drawn worldwide attention. Human monkeypox is a virus that spreads from animals to humans. It is an endemic disease in the rain forests of Central and West Africa. However, the disease recently emerged in India, and also in United States through imported wild rodents from Africa, even though the world is still struggling to escape from the clutches of the COVID-19 pandemic. Monkeypox is one of the contagious zoonotic diseases caused by the monkeypox virus (MPXV), transmitted to humans by direct contact with an infected person or animal or contact with virus-contaminated material. Its lesions are similar to smallpox in humans with various medical complications including flu-like symptoms, fever, malaise, back pain, headache, and a characteristic rash. Public health experts around the world are very concerned about the rapid spread of the infection, which has intensified efforts to find the source and cause of this phenomenon. Several viral infections with epidemic potential threaten global health security. Early recognition of cases and timely intervention of potential transmission chains are necessary to contain further outbreaks. At this early stage of monkeypox outbreaks, the current review provides updated information on the current worldwide monkeypox outbreak status, disease aetiology, clinical presentation, therapy, and preventive measures worldwide. Our review will also provide useful information to health professionals and the general public.

Monkeypox: An emerging zoonotic pathogen

Monkeypox virus (MPXV), which belongs to the orthopoxvirus genus, causes zoonotic viral disease. This review discusses the biology, epidemiology, and evolution of MPXV infection, particularly cellular, human, and viral factors, virus transmission dynamics, infection, and persistence in nature. This review also describes the role of recombination, gene loss, and gene gain in MPXV evol-vement and the role of signal transduction in MPXV infection and provides an overview of the current access to therapeutic options for the treatment and prevention of MPXV. Finally, this review highlighted gaps in knowledge and proposed future research endeavors to address the unresolved questions.

Prevention and Treatment of Monkeypox: A Systematic Review of Preclinical Studies

The outbreak of monkeypox, coupled with the onslaught of the COVID-19 pandemic is a critical communicable disease. This study aimed to systematically identify and review research done on preclinical studies focusing on the potential monkeypox treatment and immunization. The presented juxtaposition of efficacy of potential treatments and vaccination that had been tested in preclinical trials could serve as a useful primer of monkeypox virus. The literature identified using key terms such as monkeypox virus or management or vaccine stringed using Boolean operators was systematically reviewed. Pubmed, SCOPUS, Cochrane, and preprint databases were used, and screening was performed in accordance with PRISMA guidelines. A total of 467 results from registered databases and 116 from grey literature databases were screened. Of these results, 72 studies from registered databases and three grey literature studies underwent full-text screening for eligibility. In this systematic review, a total of 27 articles were eligible according to the inclusion criteria and were used. Tecovirimat, known as TPOXX or ST-246, is an antiviral drug indicated for smallpox infection whereas brincidofovir inhibits the viral DNA polymerase after incorporation into viral DNA. The ability of tecovirimat in providing protection to poxvirus-challenged animals from death had been demonstrated in a number of animal studies. Non-inferior with regard to immunogenicity was reported for the live smallpox/monkeypox vaccine compared with a single dose of a licensed live smallpox vaccine. The trial involving the live vaccine showed a geometric mean titre of vaccinia-neutralizing antibodies post two weeks of the second dose of the live smallpox/monkeypox vaccine. Of note, up to the third generation of smallpox vaccines-particularly JYNNEOS and Lc16m8-have been developed as preventive measures for MPXV infection and these vaccines had been demonstrated to have improved safety compared to the earlier generations.

Monkeypox: An Unfamiliar Virus-Clinical and Epidemiological Characteristics, Diagnosis, and Treatment with Special Emphasis on Oral Health

With the recent increased prevalence of human outbreaks, monkeypox has been recognized for decades as an infectious disease with substantial pandemic potential. The majority of cases of this virus have been observed in the European region (11,865), with few cases in the Western Pacific (54). Various governing health agencies are striving to restrain the fatal monkeypox virus (MPXV). Health practitioners around the world are learning about the many clinical manifestations of this infection, and its potential therapies. Despite the plethora of new evidence and rising cases, the essential questions remain unsolved. Thus, in this review, we have modernized the outlook for monkeypox, which will be helpful for various medical practitioners. In the light of continuing outbreaks around the world, we have also presented our assessment of the readiness of India against this outbreak, with a special focus on its effects on oral health.

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.

Strategy of developing nucleic acid-based universal monkeypox vaccine candidates

Until May 2022, zoonotic infectious disease monkeypox (MPX) caused by the monkeypox virus (MPXV) was one of the forgotten viruses considered to be geographically limited in African countries even though few cases outside of Africa were identified. Central and West African countries are known to be endemic for MPXV. However, since the number of human MPX cases has rapidly increased outside of Africa the global interest in this virus has markedly grown. The majority of infected people with MPXV have never been vaccinated against smallpox virus. Noteworthily, the MPXV spreads fast in men who have sex with men (MSM). Preventive measures against MPXV are essential to be taken, indeed, vaccination is the key. Due to the antigenic similarities, the smallpox vaccine is efficient against MPXV. Nevertheless, there is no specific MPXV vaccine until now. Nucleic acid vaccines deserve special attention since the emergency approval of two messenger RNA (mRNA)-based coronavirus disease 2019 (COVID-19) vaccines in 2020. This milestone in vaccinology has opened a new platform for developing more mRNA- or DNA-based vaccines. Certainly, this type of vaccine has a number of advantages including time- and cost-effectiveness over conventional vaccines. The platform of nucleic acid-based vaccines gives humankind a huge opportunity. Ultimately, there is a strong need for developing a universal vaccine against MPXV. This review will shed the light on the strategies for developing nucleic acid vaccines against MPXV in a timely manner. Consequently, developing nucleic acid-based vaccines may alleviate the global threat against MPXV.

The Vaccinia Virus DNA Helicase Structure from Combined Single-Particle Cryo-Electron Microscopy and AlphaFold2 Prediction

Poxviruses are large DNA viruses with a linear double-stranded DNA genome circularized at the extremities. The helicase-primase D5, composed of six identical 90 kDa subunits, is required for DNA replication. D5 consists of a primase fragment flexibly attached to the hexameric C-terminal polypeptide (res. 323-785) with confirmed nucleotide hydrolase and DNA-binding activity but an elusive helicase activity. We determined its structure by single-particle cryo-electron microscopy. It displays an AAA+ helicase core flanked by N- and C-terminal domains. Model building was greatly helped by the predicted structure of D5 using AlphaFold2. The 3.9 Å structure of the N-terminal domain forms a well-defined tight ring while the resolution decreases towards the C-terminus, still allowing the fit of the predicted structure. The N-terminal domain is partially present in papillomavirus E1 and polyomavirus LTA helicases, as well as in a bacteriophage NrS-1 helicase domain, which is also closely related to the AAA+ helicase domain of D5. Using the Pfam domain database, a D5_N domain followed by DUF5906 and Pox_D5 domains could be assigned to the cryo-EM structure, providing the first 3D structures for D5_N and Pox_D5 domains. The same domain organization has been identified in a family of putative helicases from large DNA viruses, bacteriophages, and selfish DNA elements.

Monkeypox 2022 outbreak in non-endemic countries: Open questions relevant for public health, nonpharmacological intervention and literature review

Starting from mid-May 2022, cases of human monkeypox started to rise in several non-endemic countries. By mid-July, more than 17000 confirmed/suspect cases have been reported by at least 82 countries worldwide, with a regular incremental trend. In order to contain the disease diffusion, risk evaluation is crucial to undertake informed decisions and effective communication campaigns. However, since orthopoxvirus infections so far have attracted low attention, due to the eradication of smallpox 40 years ago, and to the confinement of human monkeypox almost exclusively to endemic areas, several unresolved issues concerning natural history, ecology and pathogenesis remain. To this respect, we identified some open questions and reviewed the relevant literature on monkeypoxvirus and/or related orthopoxviruses. The results will be discussed in the perspective of their relevance to public health decisions, particularly those related to non-pharmacological interventions.

Neurologic Complications of Smallpox and Monkeypox: A Review

Importance

Orthopox viruses include smallpox virus, a once feared but now eradicated virus, as well as monkeypox virus. Monkeypox is an emerging virus initially isolated in 1958, previously unrecognized outside sub-Saharan Africa until a worldwide outbreak in May 2022. It is important to review known neurologic consequences of both these viruses, as complications of smallpox may be relevant to monkeypox, though complications of monkeypox may be rarer and perhaps less severe.

Observations

This was a literature review of the known neurologic complications of smallpox, which include encephalitis, transverse myelitis, and acute disseminated encephalomyelitis among others; historical complications of smallpox vaccination, including postvaccinal encephalomyelitis; and the known neurologic complications of monkeypox, which include headaches and mood disturbances, as well as rare presentations of encephalitis, transverse myelitis, and seizures. Of concern is the possibility of viral persistence and systemic complications in immunocompromised individuals. Also provided were considerations for diagnosis, current treatment, and prevention of monkeypox.

Conclusions and Relevance

Monkeypox should be considered in high-risk populations who present with neurologic syndromes. Diagnosis may require serology and polymerase chain reaction testing of blood and spinal fluid. Antiviral therapy should be initiated early in the course of the illness.

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.

In this Review, Ng and colleagues examine the clinical, epidemiological and immunological aspects of monkeypox virus (MPXV) infections, with a focus on mechanisms of host immunity to MPXV. The authors also consider the unique epidemiological and pathological characteristics of the current non-endemic outbreak of the virus and discuss vaccines, therapeutics and outstanding research questions.

Monkeypox, a Literature Review: What Is New and Where Does This concerning Virus Come From?

Among the Poxviridae family, orthopoxvirus is the most notorious genus. Several DNA viruses belonging to this group are known to produce human disease from the life-threatening variola virus (VARV) (the causative agent of smallpox), monkeypox virus (MPXV), cowpox virus (CPXV), and vaccinia virus (VACV). These orthopoxviruses still remain a public health concern as VACV or CPXV still cause emerging endemic threads, especially in developing countries. MPXV is able to cause sporadic human outbreaks of a smallpox-like zoonotic disease and, in May 2022, hundreds of cases related to MPXV have been reported from more than 30 countries around the globe. At the end of July, monkeypox (MPX) outbreak was even declared a global health emergency by the World Health Organization (WHO). Many aspects remain unclear regarding this outbreak and a deep understanding of orthopoxvirus might have crucial and evident implications. During the era in which people under 45 years old are not protected against VACV, the potential use of orthopoxviruses as a biological weapon raises global concern considering the rapid spreading of the current MPX outbreak in vulnerable populations. Hence, we review the most recent evidence about phylogenesis, pathogenesis, prevention, and treatment for this concerning disease.

Monkeypox: Some Keys to Understand This Emerging Disease

In 1958, several monkeys in a Copenhagen laboratory developed a skin rash from which an orthopoxvirus could be isolated, which was named monkeypox virus (MPXV). However, the natural animal reservoir for MPXV is thought to be a rodent. The first human case occurred in 1970, and the incidence has increased progressively throughout the years. Starting May 2022, the number of cases outside Africa has soared, especially in Western Europe. There are two clades of MPXV, Congo Basin, with higher virulence and mortality, and Western Africa (WA). MPXV from the present outbreak has been proposed to be classified as Clade 3, distinct from the WA clade by at least 50 substitutions, which may increase human-to-human transmissibility. Most cases correspond to men in their 30s who have sex with men, and the possibility of sexual transmission is under investigation. Though there is no evidence of human-to-animal transmission, pets of positive human cases may be classified as low risk, including dogs, cats, and birds, who can be quarantined at home, and high risk, such as pet rabbits or mice, who should be isolated in official laboratories for observation. The current epidemiological data do not support the risk of a pandemic.

Prevention and Treatment of Monkeypox: A Step-by-Step Guide for Healthcare Professionals and General Population

The World Health Organization (WHO) recently declared the monkeypox virus a Public Health Emergency of International Concern (PHEIC). As the cases of the COVID-19 pandemic start to get under control, we have seen the monkeypox virus, found predominantly in Africa, spread in non-endemic countries worldwide. In the 1970s, after the smallpox virus eradication and the vaccine's discontinuation, the monkeypox virus infection started to gain attention. The first United States outbreak happened in 2003; since then, more sporadic cases of monkeypox have gained media attention. With cases spreading worldwide, without epidemiological links with outbreaks among men who have sex with men (MSM), it warrants urgent public health control measures to contain the spread of the monkeypox virus and investigate the underlying pathophysiology, including genetic modification of the virus. This review highlights the epidemiology, transmission, pathogenesis, clinical manifestation, diagnosis, prevention, and management of the current human monkeypox virus infection.

Human Monkeypox: A Comprehensive Narrative Review and Analysis of the Public Health Implications

Recently, numerous cases of monkeypox were reported from several non-endemic countries in Europe, North America, and Oceania, suggesting an unusual and alarming public health issue, particularly considering that the disease is not directly related to human or animal travels. Attention is currently being drawn to this phenomenon since more than 70% of the global population is no longer vaccinated against smallpox. Indeed, the smallpox vaccination also confers some indirect degree of protection against other poxviruses, including monkeypox. We performed a narrative review to describe the existing literature with regard to monkeypox using the MEDLINE, EMBASE, and Scopus databases. This review aims to provide updated evidence of findings on the epidemiology, clinical features, diagnosis, management, and prevention of monkeypox, also considering the concurrent zoonotic pandemic caused by the COVID-19 coronavirus, SARS-CoV-2.