Unusual global outbreak of monkeypox: what should we do?

Rapid identification of A29L antibodies based on mRNA immunization and high-throughput single B cell sequencing to detect Monkeypox virus

With the large number of atypical cases in the mpox outbreak, which was classified as a global health emergency by the World Health Organization (WHO) on 23 July 2022, rapid diagnosis of mpox and diseases with similar symptoms to mpox such as chickenpox and respiratory infectious diseases in the early stages of viral infection is key to controlling the spread of the outbreak. In this study, antibodies against the monkeypox virus A29L protein were efficiently and rapidly identified by combining rapid mRNA immunization with high-throughput sequencing of individual B cells. We obtained eight antibodies with a high affinity for A29L validated by ELISA, which were was used as the basis for developing an ultrasensitive fluorescent immunochromatographic assay based on multilayer quantum dot nanobeads (SiTQD-ICA). The SiTQD-ICA biosensor utilizing M53 and M78 antibodies showed high sensitivity and stability of detection: A29L was detected within 20 min, with a minimum detection limit of 5 pg/mL. A specificity test showed that the method was non-cross-reactive with chickenpox or common respiratory pathogens and can be used for early and rapid diagnosis of monkeypox virus infection by antigen detection. This antibody identification method can also be used for rapid acquisition of monoclonal antibodies in early outbreaks of other infectious diseases for various studies.

Dynamics of Mpox infection in Nigeria: a systematic review and meta-analysis

The seasonal outbreaks of Mpox continue in most parts of West and Central Africa. In the past year, Nigeria had the highest number of reported cases. Here, we used the PRISMA guidelines to carry out a systematic review and meta-analysis of available evidence on Mpox in Nigeria to assess the prevalence, transmission pattern, diagnostic approach, and other associated factors useful for mitigating the transmission of the disease. All relevant observational studies in PubMed/MEDLINE, Embase, AJOL, Web of Science, Scopus and Google Scholar on Mpox in Nigeria were assessed within the last fifty years (1972 to 2022). In all, 92 relevant articles were retrieved, out of which 23 were included in the final qualitative analysis. Notably, most of the cases of Mpox in Nigeria were from the southern part of the country. Our findings showed a progressive spread from the southern to the northern region of the country. We identified the following factors as important in the transmission of Mpox in Nigeria; poverty, lack of basic healthcare facilities, and risk of exposure through unsafe sexual practices. Our findings reiterate the need to strengthen and expand existing efforts as well as establish robust multi-sectoral collaboration to understand the dynamics of Mpox Nigeria.

Ultrasensitive one-pot detection of monkeypox virus with RPA and CRISPR in a sucrose-aided multiphase aqueous system

IMPORTANCE

The monkeypox virus was declared as a Public Health Emergency of International Concern (PHEIC) by the World Health Organization (WHO) and continues to cause infection cases worldwide. Given the risk of virus evolution, it is essential to identify monkeypox virus infection in a timely manner to prevent outbreaks. This study establishes a novel one-pot recombinase polymerase amplification-Clustered Regularly Interspaced Short Palindromic Repeats (RPA-CRISPR) assay for monkeypox virus with an ultra-high sensitivity. The assay shows good specificity, accuracy, and the rapidness and convenience important for point-of-care testing. It provides an effective tool for the early diagnosis of monkeypox, which is useful for the prevention of an epidemic.

Assessing the Anxiety and Knowledge about Monkeypox Virus: A Cross-Sectional Cohort Study

Introduction Recent cases of human monkeypox virus (MPXV) infections have raised global health concerns, as sporadic instances have occurred in various regions, prompting investigations into the potential for increased transmission. This underscores the importance of effective communication strategies in addressing the emerging challenges associated with this viral ailment. The study was conducted to understand public anxiety and knowledge related to MPXV infection, particularly in the context of emerging infectious diseases. Our aims included assessing anxiety levels and knowledge about monkeypox infection among the Saudi population, as well as their willingness to receive vaccinations if available. Methods A cross-sectional cohort study among the adult Saudi population was conducted. A questionnaire with four sections, including demographic data and disease knowledge, comprised optimized questions of the standard generalized anxiety disorder assessment (GAD-7) as well as questions related to acceptance of getting the vaccine if it could be afforded. Results Out of a total of 5298 participants, 927 (17.5%) showed different degrees of GAD-7 anxiety. Females showed a significantly higher rate of anxiety (487/2189, 22.2%) than males (440/3109, 14.2%). People aged 46 to 55 and >55 years old showed significantly higher rates of anxiety (30.7% and 27.2%). There is an overall decrease in knowledge and awareness about the MPXV. Interestingly, 59% of the participants admitted that they would get the MPXV vaccine if it were made available. There was a positive correlation between the anxiety level and the response of people toward the MPXV vaccine if it were available. Conclusion Our study underscores a significant level of anxiety and a notable lack of awareness concerning MPXV infection. Although a substantial number of participants expressed their willingness to receive an MPXV vaccine, our findings emphasize the pressing need for improved public education and awareness campaigns to alleviate anxiety levels and enhance understanding of this infectious disease. This effort is crucial for mitigating health concerns and facilitating well-informed decision-making among the Saudi population.

Design, evaluation, and immune simulation of potentially universal multi-epitope mpox vaccine candidate: focus on DNA vaccine

Monkeypox (mpox) is a zoonotic infectious disease caused by the mpox virus. Mpox symptoms are similar to smallpox with less severity and lower mortality. As yet mpox virus is not characterized by as high transmissibility as some severe acute respiratory syndrome 2 (SARS-CoV-2) variants, still, it is spreading, especially among men who have sex with men (MSM). Thus, taking preventive measures, such as vaccination, is highly recommended. While the smallpox vaccine has demonstrated considerable efficacy against the mpox virus due to the antigenic similarities, the development of a universal anti-mpox vaccine remains a necessary pursuit. Recently, nucleic acid vaccines have garnered special attention owing to their numerous advantages compared to traditional vaccines. Importantly, DNA vaccines have certain advantages over mRNA vaccines. In this study, a potentially universal DNA vaccine candidate against mpox based on conserved epitopes was designed and its efficacy was evaluated via an immunoinformatics approach. The vaccine candidate demonstrated potent humoral and cellular immune responses in silico, indicating the potential efficacy in vivo and the need for further research.

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.

Development of a Multi-Epitope Universal mRNA Vaccine Candidate for Monkeypox, Smallpox, and Vaccinia Viruses: Design and In Silico Analyses

Notwithstanding the presence of a smallpox vaccine that is effective against monkeypox (mpox), developing a universal vaccine candidate against monkeypox virus (MPXV) is highly required as the mpox multi-country outbreak has increased global concern. MPXV, along with variola virus (VARV) and vaccinia virus (VACV), belongs to the Orthopoxvirus genus. Due to the genetic similarity of antigens in this study, we have designed a potentially universal mRNA vaccine based on conserved epitopes that are specific to these three viruses. In order to design a potentially universal mRNA vaccine, antigens A29, A30, A35, B6, and M1 were selected. The conserved sequences among the three viral species-MPXV, VACV, and VARV-were detected, and B and T cell epitopes containing the conserved elements were used for the design of the multi-epitope mRNA construct. Immunoinformatics analyses demonstrated the stability of the vaccine construct and optimal binding to MHC molecules. Humoral and cellular immune responses were induced by immune simulation analyses. Eventually, based on in silico analysis, the universal mRNA multi-epitope vaccine candidate designed in this study may have a potential protection against MPXV, VARV, and VACV that will contribute to the advancement of prevention strategies for unpredictable pandemics.

Monkeypox: another pandemic in the making?

Monkeypox is a zoonotic disease caused by the monkeypox virus, which is a member of the Poxviridae family of viruses. It is transmitted through direct or indirect contact with fluid secretions. Initial symptoms include fever, chills, headache, and malaise, followed by a maculopapular rash that starts on the face and progresses centrifugally. Polymerase chain reaction is the preferred laboratory test for the diagnosis, and management is mostly supportive. The clinical presentation of monkeypox is quite similar to that of another member of the Poxviridae family: smallpox, which wreaked havoc in the 20th century, before being eradicated with the help of the vaccinia virus vaccine in 1977. This vaccine protects not only against smallpox but also monkeypox; therefore, when use of this vaccine was discontinued, monkeypox had a new susceptible population to infect and way to proliferate and evolve. Initially the disease spread in Africa, but now the more evolved monkeypox is quickly spreading to other countries. On July 23, 2022, the World Health Organization declared this multicountry outbreak a public health emergency of international concern. Given its mutating ability and high transmissibility, we need to quickly devise measures to control this virus before it turns into a pandemic.

Antiviral activities of ginseng and its potential and putative benefits against monkeypox virus: A mini review

Due to the Covid-19 pandemic more than 6 million people have died, and it has bought unprecedented challenges to our lives. The recent outbreak of monkeypox virus (MPXV) has brought out new tensions among the scientific community. Currently, there is no specific treatment protocol for MPXV. Several antivirals, vaccinia immune globulin (VIG) and smallpox vaccines have been used to treat MPXV. Ginseng, one of the more famous among traditional medicines, has been used for infectious disease for thousands of years. It has shown promising antiviral effects. Ginseng could be used as a potential adaptogenic agent to help prevent infection by MPXV along with other drugs and vaccines. In this mini review, we explore the possible use of ginseng in MPXV prevention based on its antiviral activity.

Orthopoxvirus Zoonoses—Do We Still Remember and Are Ready to Fight?

The eradication of smallpox was an enormous achievement due to the global vaccination program launched by World Health Organization. The cessation of the vaccination program led to steadily declining herd immunity against smallpox, causing a health emergency of global concern. The smallpox vaccines induced strong, humoral, and cell-mediated immune responses, protecting for decades after immunization, not only against smallpox but also against other zoonotic orthopoxviruses that now represent a significant threat to public health. Here we review the major aspects regarding orthopoxviruses’ zoonotic infections, factors responsible for viral transmissions, as well as the emerging problem of the increased number of monkeypox cases recently reported. The development of prophylactic measures against poxvirus infections, especially the current threat caused by the monkeypox virus, requires a profound understanding of poxvirus immunobiology. The utilization of animal and cell line models has provided good insight into host antiviral defenses as well as orthopoxvirus evasion mechanisms. To survive within a host, orthopoxviruses encode a large number of proteins that subvert inflammatory and immune pathways. The circumvention of viral evasion strategies and the enhancement of major host defenses are key in designing novel, safer vaccines, and should become the targets of antiviral therapies in treating poxvirus infections.

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.

G-quadruplexes in the monkeypox virus are potential antiviral targets

Monkeypox virus (MPXV) is a member of Orthopoxvirus in the Poxviridae family, causing a Public Health Emergency of International Concern. The number of cases and geographic range has increased significantly in 2022. Identification of MPXV-specific therapeutic targets is urgent. G-quadruplex (GQ) secondary structures attract great attention as potential targets for antiviral strategy. Whether GQs are present in the MPXV genome remains inconclusive. In this study, we aim to characterize the GQs encoded by MPXV. Through a series of biophysical experiments, we characterized the formation potential of MPXV-encoded GQs and evaluated the binding and stabilization abilities of GQ ligands including BRACO-19, pyridostatin, and TMPyP4 to GQs encoded by MPXV. Moreover, GQ ligands suppressed the gene transcription of MPXV sequences containing GQ. BRACO-19 and TMPyP4 were able to inhibit vaccinia virus replication. We demonstrated the existence of MPXV GQ and reinforced the idea that GQs could be novel antiviral targets. Targeting these GQ sequences with GQ-binding molecules may represent a new approach for MPXV therapy.

Evaluation and validation of an RT-PCR assay for specific detection of monkeypox virus (MPXV)

Monkeypox virus (MPXV) is a zoonotic orthopoxvirus within the Poxviridae family. MPXV is endemic to Central and West Africa. However, the world is currently witnessing an international outbreak with no clear epidemiological links to travel or animal exposure and with ever-increasing numbers of reported cases worldwide. Here, we evaluated and validated a new, sensitive, and specific real-time PCR-assay for MPXV diagnosis in humans and compare the performance of this novel assay against a Food & Drug Administration-cleared pan-Orthopox RT-PCR assay. We determined specificity, sensitivity, and analytic performance of the PKamp™ Monkeypox Virus RT-PCR assay targeting the viral F3L-gene. In addition, we further evaluated MPXV-PCR-positive specimens by viral culture, electron microscopy, and viral inactivation assays. The limit of detection was established at 7.2 genome copies/reaction, and MPXV was successfully identified in 20 clinical specimens with 100% correlation against the reference method with 100% sensitivity and specificity. Our results demonstrated the validity of this rapid, robust, and reliable RT-PCR assay for specific and accurate diagnosis of MPXV infection in human specimens collected both as dry swabs and in viral transport media. This assay has been approved by NYS Department of Health for clinical use.

Monkeypox: Treatment, Vaccination, and Prevention

In regions where the disease is endemic, Monkeypox (MPV) transmission related to healthcare has been seen on numerous occasions. This disease has episodes of occurrence in certain regions around the globe, such as in the Democratic Republic of Congo's (DRC) Tshuapa region. Here, the disease was found with a prevalence of 0.35 per 1000, as per data collected by the Centers for Disease Control and Prevention (CDC) of the United States (US). Data also shows approximately 100 confirmed cases of MPV for every infection among Healthcare Workers (HCWs). These findings and scientific research on burns, superficial wounds, herpes, eczema vaccine, and other conditions indicate that MPV sufferers might get an advantage from medical care to lessen the effects of weakened skin and mucosa. This should involve guarding delicate anatomical areas like the eyes and genitalia, maintaining enough hydration and nourishment, and preventing and treating consequences like secondary bacterial diseases. In the DRC, this disease was first recognized in 1970. Since then, it has spread to numerous nations around the globe and gained substantial epidemiological significance. The most recent epidemic has taken place in 2022 worldwide. The viruses that cause MPV and cowpox are currently regarded as emerging. Because of the rise in international travel, the popularity of exotic pets, and the decline in smallpox vaccination rates, they pose a significant danger of spreading. Although it is believed that this viral illness will eventually go away on its own, the possibility of the pandemic raises several serious problems for the general public's health. In addition to providing a broad overview of the Monkeypox Virus (MPXV), this study will detail the epidemiology, clinical hallmarks, assessment, and treatment of MPV sufferers.

Smallpox, Monkeypox and Other Human Orthopoxvirus Infections

Considering that vaccination against smallpox with live vaccinia virus led to serious adverse effects in some cases, the WHO, after declaration of the global eradication of smallpox in 1980, strongly recommended to discontinue the vaccination in all countries. This led to the loss of immunity against not only smallpox but also other zoonotic orthopoxvirus infections in humans over the past years. An increasing number of human infections with zoonotic orthopoxviruses and, first of all, monkeypox, force us to reconsider a possible re-emergence of smallpox or a similar disease as a result of natural evolution of these viruses. The review contains a brief analysis of the results of studies on genomic organization and evolution of human pathogenic orthopoxviruses, development of modern methods for diagnosis, vaccination, and chemotherapy of smallpox, monkeypox, and other zoonotic human orthopoxvirus infections.

First Case of Monkeypox in Venezuela: Partial Complete Genome Sequence Allowed Its Grouping into the West African Clade II

The ongoing epidemic of monkeypox virus (MPXV) infection has already reached more than 50,000 persons worldwide until the end of August 2022. We report the first case detected in Venezuela. The patient reported traveling from Spain and contact with friends tested positive for MPXV after his return. Partial complete genome phylogenetic analysis allowed to group the isolate within the clade II of MPXV, the major one circulating worldwide. No other case of MPXV has been detected until the end of August 2022 in the country, although the presence of undiagnosed cases due to the fear of stigmatization cannot be ruled out.

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.

Assessing Healthcare Workers' Knowledge and Their Confidence in the Diagnosis and Management of Human Monkeypox: A Cross-Sectional Study in a Middle Eastern Country

The ongoing multi-country human monkeypox (HMPX) outbreak was declared as a public health emergency of international concern. Considering the key role of healthcare workers (HCWs) in mitigating the HMPX outbreak, we aimed to assess their level of knowledge and their confidence in diagnosis and management of the disease, besides the assessment of their attitude towards emerging virus infections from a conspiracy point of view. An online survey was distributed among HCWs in Jordan, a Middle Eastern country, during May−July 2022 using a questionnaire published in a previous study among university students in health schools in Jordan. The study sample comprised 606 HCWs, with about two-thirds being either physicians (n = 204, 33.7%) or nurses (n = 190, 31.4%). Four out of the 11 HMPX knowledge items had <50% correct responses with only 33.3% of the study respondents having previous knowledge that vaccination is available to prevent HMPX. A majority of study respondents (n = 356, 58.7%) strongly agreed, agreed or somewhat agreed that the spread of HMPX is related to a role of male homosexuals. Confidence in the ability of diagnosis based on the available monkeypox virus diagnostic tests was reported by 50.2% of the respondents, while the confidence levels were lower for the ability to manage (38.9%) and to diagnose (38.0%) HMPX cases based on their current level of knowledge and skills. Higher confidence levels for HMPX diagnosis and management were found among physicians compared to nurses. The endorsement of conspiracy beliefs about virus emergence was associated with lower HMPX knowledge, the belief in the role of male homosexuals in HMPX spread, and with lower diagnosis and management confidence levels. The current study highlighted the gaps in knowledge regarding HMPX among HCWs in Jordan as well as the lack of confidence to diagnose and manage cases among physicians and nurses. Raising the awareness about the disease is needed urgently considering the rapid escalation in the number of cases worldwide with reported cases in the Middle East. The attitude towards male homosexuals’ role in HMPX spread necessitates proper intervention measures to prevent stigma and discrimination among this risk group. The adoption of conspiratorial beliefs regarding virus emergence was widely prevalent and this issue needs to be addressed with proper and accurate knowledge considering its potential harmful impact.

Monkeypox Knowledge and Confidence in Diagnosis and Management with Evaluation of Emerging Virus Infection Conspiracies among Health Professionals in Kuwait

As the 2022 human monkeypox (HMPX) multi-country outbreak is spreading, the response of healthcare workers (HCWs) is central to mitigation efforts. The current study aimed to evaluate HMPX knowledge and confidence in diagnosis and management among HCWs in Kuwait. We used a self-administered questionnaire distributed in July-August 2022 through a snowball sampling approach. The survey items evaluated HMPX knowledge, confidence in diagnosis and management of the disease, and the belief in conspiracies regarding emerging virus infections (EVIs). The sample size was 896 HCWs: nurses (n = 485, 54.1%), pharmacists (n = 154, 17.2%), physicians (n = 108, 12.1%), medical technicians/allied health professionals (MT/AHP, n = 96, 10.7%), and dentists (n = 53, 5.9%). An overall low level of HMPX knowledge was noticed for items assessing virus transmission and non-cutaneous symptoms of the disease, with higher knowledge among physicians. Approximately one-fifth of the study sample agreed with the false notion that HMPX is exclusive to male homosexuals (n = 183, 20.4%), which was associated with lower knowledge with higher frequency among MT/AHP compared to nurses, physicians, and pharmacists. Confidence levels were low: confidence in diagnosis based on diagnostic tests (n = 449, 50.1%), confidence in the ability to manage the HMPX (n = 426, 47.5%), and confidence in the ability to diagnose HMPX clinically (n = 289, 32.3%). Higher confidence levels were found among nurses and participants with postgraduate degrees. Higher embrace of conspiracy beliefs regarding EVIs was noticed among participants with lower knowledge, and among those who agreed or were neutral/had no opinion regarding the false idea of HMPX exclusive occurrence among male homosexuals, while lower levels of belief in conspiracies were noticed among physicians, dentists, and pharmacists compared to MT/AHP. Variable levels of HMPX knowledge were observed in this study per item, with low level of knowledge regarding virus transmission. Differences in knowledge and confidence levels in diagnosis and management of HMPX should be considered in education and training aiming to prepare for outbreak response. The relatively high prevalence of embracing conspiratorial beliefs regarding EVIs is worrisome and needs proper interventions. The attitude towards male homosexuals' role in monkeypox spread should be evaluated in future studies considering the possibility of stigma and discrimination in this most-at-risk group.

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.