Clinical spectrum of human monkeypox: An Italian single-centre case series

Long or complicated mpox in patients with uncontrolled HIV infection

To date, former research about the impact of HIV infection on mpox poor outcomes is still limited and controversial. Therefore, the aim of this study was to assess the impact of HIV on the clinical course of mpox, in a large population of patients from Spain. Nationwide case-series study. Patients from 18 Spanish hospitals, with PCR-confirmed mpox from April 27, 2022 to June 30, 2023 were included in this study. The main outcome was the development of long or complicated (LC) mpox, defined as: (i) duration of the clinical course ≥ 28 days, or; (ii) disseminated disease, or: (iii) emergence of severe complications. One thousand eight hundred twenty-three individuals were included. Seven hundred eighty-six (43%) were people living with HIV (PLWH), of whom 11 (1%) had a CD4 cell count < 200 cells/mm3 and 33 (3%) <350 cells/mm3 . HIV viral load ≥ 1000 cp/mL was found in 27 (3%) PLWH, none of them were on effective ART. Fifteen (60%) PLWH with HIV-RNA ≥ 1000 cp/mL showed LC versus 182 (29%) PLWH with plasma HIV-RNA load < 1000 copies/mL and 192 (24%) individuals without HIV infection (p < 0.001). In multivariate analysis, adjusted by age, sex, CD4 cell counts and HIV viral load at the time of mpox, only plasma HIV-RNA ≥ 1000 cp/mL was associated with a greater risk of developing LC mpox [adjusted OR = 4.06 (95% confidence interval 1.57-10.51), p = 0.004]. PLWH with uncontrolled HIV infection, due to lack of ART, are at a greater risk of developing LC mpox. Efforts should be made to ensure HIV testing is carried out in patients with mpox and to start ART without delay in those tested positive.

A global systematic evidence review with meta-analysis of the epidemiological characteristics of the 2022 Mpox outbreaks

BACKGROUND

In 2022, there were outbreaks of Mpox where the disease is not endemic. We summarized published full-text epidemiological data from the outbreaks.

METHODS

A global evidence review (protocol: osf.io/j3kb7) with systematic literature search up to February 09, 2023. We focused on experimental/observational studies of laboratory confirmed Mpox, excluding case reports and case series of < 5 cases. Epidemiological data were pooled using an inverse variance, random-effects model, and pooled estimates presented with associated 95% confidence intervals.

RESULTS

We included 66 studies. Mean incubation period was 7.8 days (6.6-9.0 days, 8 studies: 560 cases), reproductive number 1.8 (1.7-1.9, 6 studies), mean duration from symptom onset to diagnosis 5.8 days (4.8-6.8 days, 4 studies: 982 cases), mean symptom duration 17.5 days (14.7-20.2 days, 3 studies: 292 cases), mean serial interval 8.5 days (7.3-9.9 days, 1 study), hospitalisation 6% (4-9%, 26 studies: 5339 cases), and vaccine effectiveness 78% (65-91%, 3 studies: 953 cases). Highly relevant clinical manifestations were pleomorphic skin lesions 82% (68-94%, 26 studies: 4093 cases), anogenital lesions 64% (51-77%, 9 studies: 10,398 cases), fever 54% (50-57%, 52 studies: 25,992 cases), and lymphadenopathy 51% (46-57%, 42 studies: 17,803 cases), with cases mostly men who have sex with men (MSM). Possibly relevant manifestations were perianal lesions, fatigue, asthenia, myalgia, and headache.

CONCLUSIONS

The 2022 Mpox outbreaks presented with sex-related clinical manifestations and were mostly reported among MSM.

Mpox: an updated review of dermatological manifestations in the current outbreak

Mpox is a disease caused by a double-stranded DNA orthopoxvirus discovered in 1958. In 2022, an outbreak on an unprecedented scale marked its transition from neglected, zoonotic disease circulating almost exclusively within African borders to sexually transmitted infection (STI) of international concern. Although phylogenetic evidence suggests progressive evolution from the strain associated with the 2018 outbreak in Nigeria, epidemiological links with previous cases have still not been completely elucidated. Clinically, mpox presents with systemic symptoms, such as fever, headache, malaise and a characteristic cutaneous eruption, similar to that of cognate viruses (e.g. smallpox). Mpox pseudopustules evolve through several stages, including umbilication and crusting, and resolve in the span of 2-3 weeks. The hallmarks that set the 2022 outbreak apart from classic mpox were a disproportionate number of cases occurring in men who have sex with men, an often localized cutaneous picture and a significant burden in terms of concomitant STIs. Investigations into the disease pathogenesis, related immune response, clinical and dermoscopic features, in addition to studies aimed at defining novel management strategies, have advanced mpox knowledge considerably. Herein, recent findings on mpox are reviewed, with a keen focus on dermatological manifestations and their implications in the current diagnostic scenario, reinforcing the pivotal role of dermatologists in managing suspect cases and preventing further spread of the contagion.

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.

Monkeypox: A Histopathological and Transmission Electron Microscopy Study

The global outbreak of human monkeypox virus (hMPXV1) in 2022 highlighted the usefulness of dermatological manifestations for its diagnosis. Infection by the human monkeypox virus thus necessitated inclusion in the diagnostic repertoire of dermatopathology. To assess the histopathological and microscopical findings of cutaneous lesions related to hMPXV infection, we analyzed skin biopsies from patients with positive MPXV DNA polymerase chain reaction presenting with a typical course of hMPXV1 infection. The most prominent histopathological findings were ascribable to a pustular stage in which epidermal necrosis with areas of non-viable keratinocytes and a "shadow cell" appearance were evident; in some cases, the deep portion of the hair follicle and the acrosyringial epithelium were affected. The main cytopathic modifications included ballooning keratinocytes, followed by Guarnieri bodies and a ground glass appearance of the keratinocytes' nuclei, together with a dense mixed inflammatory cell infiltrate with prominent neutrophil exocytosis. Transmission electron microscopy analysis demonstrated viral particle aggregates in the cytoplasm of keratinocytes, without any involvement of the nucleus. Interestingly, we also found the presence of viral particles in infected mesenchymal cells, although to a lesser extent than in epithelial cells. Through this study, we contributed to expanding the histological and microscopic knowledge of the human mpox virus, a key step to understanding current and potential future trends of the disease, as well as of other Orthopoxvirus infections.

Whole-genome sequencing of hMPXV1 in five Italian cases confirms the occurrence of the predominant epidemic lineage

The ongoing outbreak of monkeypox virus (hMPXV1) is the largest recorded in historically nonendemic countries. Genomic surveillance has emerged as a pivotal tool to track the spread and monitor the evolution of viral pathogens. Therefore, to assess the genetic diversity of circulating hMPXV1 in northern Italy in June to July 2022, we sequenced and analyzed five complete genomes of viruses sampled from patients presenting with a typical course of hMPXV1 infection. Phylogenetic analysis confirmed that all five genomes belong to the predominant epidemic lineage (B.1). Inspection of genetic changes and comparison with the reference sequence showed the presence of 12 nucleotide substitutions. Seven are nonsynonymous mutations leading to amino acid changes in six proteins belonging to different functional classes. Moreover, 11 of these 12 nucleotide mutations involve GA>AA or TC>TT replacements, suggesting that host APOBEC3 enzymes are responsible for the generation of substitutions in circulating viruses. Finally, metagenomic analysis evidenced bacterial superinfection (Streptococcus pyogenes) in one patient. Through this study, we contributed to expand the number of complete genomes of viruses circulating in Italy and characterize them as belonging to the predominant outbreak lineage.

Monkeypox outbreak in Genoa, Italy: Clinical, laboratory, histopathologic features, management, and outcome of the infected patients

Since May 2022, multiple human Monkeypox cases were identified in nonendemic countries, mainly among men who have sex with men. We aimed to report the features, clinical course, management, and outcome of the Monkeypox cases diagnosed in the Dermatology and Infectious Disease Units of the San Martino Hospital, Genoa, Italy. We performed an observational study of the Monkeypox cases diagnosed from July 1 until August 31, 2022, collecting clinical, laboratory, and histological data. We studied 16 Monkeypox-infected men (14 homosexual, 2 bisexual) with a median age of 37 years. Three were HIV-infected. All patients reported multiple sexual partners and/or unprotected sex in the 2 weeks before the diagnosis. Most patients had prodromal signs/symptoms before the appearance of the skin/mucosal eruption, consisting of erythematous papules/vesicles/pustules in the anogenital area, which tended to erode evolving into crusts and ulcers. Lesions were often associated with local and/or systemic symptoms. Histopathology showed overlapping features in all cases: epidermal ulceration and dermal inflammatory infiltrate consisting of lymphocytes and neutrophils with an interstitial and perivascular/peri-adnexal pattern and endothelial swelling. Concomitant sexually transmitted infections (STIs) (gonococcal/nongonococcal proctitis and anal high-risk human papillomavirus [HR-HPV] infection) were frequent. Four patients were hospitalized, and one received specific treatment. The overall outcome was good. At the follow-up visit, three patients presented skin scars. Our series confirms the features of the current Monkeypox outbreak; however, different from other studies, we found a considerable rate of concomitant STIs, such as anal HR-HPV infection, that should be kept in mind because this persistent infection is the main cause of anal cancers.

Clinical Characteristics of Human Mpox (Monkeypox) in 2022: A Systematic Review and Meta-Analysis

Since May 2022, large numbers of human mpox (previously known as monkeypox) cases have been reported in non-endemic regions. We conducted a systematic review and meta-analysis to elucidate clinical characteristics of the current mpox outbreak. Our systematic review and meta-analysis were undertaken according to PRISMA and MOOSE guidelines. We searched PubMed, EMBASE, and Web of Science for publications between 1 January and 11 November 2022. Random-effects models were used to pool results. Heterogeneity was assessed using I2. This study is registered with PROSPERO, CRD42022355590. Skin lesions (95.2%, 95% CI [93.3-96.9%]), fever (58.4%, [54.9-61.8%]) and lymphadenopathy (53.0%, [48.7-57.3%]) were the most common symptoms. The most common dermatological manifestations were anogenital lesions (65.7%, [57.8-73.0%]), and the most common lymphadenopathy was inguinal (46.8%, [40.6-53.0%]). There were no differences in symptoms including malaise, fever, headache, and genital, anal, and oropharyngeal lesions according to HIV infection status. Median age of patients varied from 15 to 57.5 years (median, 35 years). The median proportion of men who had sex with men (MSM) was 100.0% (20.6-100.0%). The median proportion of patients who reported recent sexual exposure was 99.2% (14.3-100.0%). The median proportion of PLHIV was 42.2% (0.0-100.0%). Skin lesions, fever, inguinal lymphadenopathy, and anogenital lesions were the most common symptoms of mpox reported in the current outbreak. Existing guidelines should be updated to reflect these clinical manifestations and groups at highest risk of infection, MSM in particular.

Potential therapeutic targets for Mpox: the evidence to date

INTRODUCTION

The global Mpox (MPX) disease outbreak caused by the Mpox virus (MPXV) in 2022 alarmed the World Health Organization (WHO) and health regulation agencies of individual countries leading to the declaration of MPX as a Public Health Emergency. Owing to the genetic similarities between smallpox-causing poxvirus and MPXV, vaccine JYNNEOS, and anti-smallpox drugs Brincidofovir and Tecovirimat were granted emergency use authorization by the United States Food and Drug Administration. The WHO also included cidofovir, NIOCH-14, and other vaccines as treatment options.

AREAS COVERED

This article covers the historical development of EUA-granted antivirals, resistance to these antivirals, and the projected impact of signature mutations on the potency of antivirals against currently circulating MPXV. Since a high prevalence of MPXV infections in individuals coinfected with HIV and MPXV, the treatment results among these individuals have been included.

EXPERT OPINION

All EUA-granted drugs have been approved for smallpox treatment. These antivirals show good potency against Mpox. However, conserved resistance mutation positions in MPXV and related poxviruses, and the signature mutations in the 2022 MPXV can potentially compromise the efficacy of the EUA-granted treatments. Therefore, MPXV-specific medications are required not only for the current but also for possible future outbreaks.

Association between Global Monkeypox Cases and Meteorological Factors

The emergence of an outbreak of Monkeypox disease (MPXD) is caused by a contagious zoonotic Monkeypox virus (MPXV) that has spread globally. Yet, there is no study investigating the effect of climatic changes on MPXV transmission. Thus, studies on the changing epidemiology, evolving nature of the virus, and ecological niche are highly paramount. Determination of the role of potential meteorological drivers including temperature, precipitation, relative humidity, dew point, wind speed, and surface pressure is beneficial to understand the MPXD outbreak. This study examines the changes in MPXV cases over time while assessing the meteorological characteristics that could impact these disparities from the onset of the global outbreak. To conduct this data-based research, several well-accepted statistical techniques including Simple Exponential Smoothing (SES), Auto-Regressive Integrated Moving Average (ARIMA), Automatic forecasting time-series model (Prophet), and Autoregressive Integrated Moving Average with Explanatory Variables (ARIMAX) were applied to delineate the correlation of the meteorological factors on global daily Monkeypox cases. Data on MPXV cases including affected countries spanning from 6 May 2022, to 9 November 2022, from global databases and meteorological data were used to evaluate the developed models. According to the ARIMAX model, the results showed that temperature, relative humidity, and surface pressure have a positive impact [(51.56, 95% confidence interval (CI): -274.55 to 377.68), (17.32, 95% CI: -83.71 to 118.35) and (23.42, 95% CI: -9.90 to 56.75), respectively] on MPXV cases. In addition, dew/frost point, precipitation, and wind speed show a significant negative impact on MPXD cases. The Prophet model showed a significant correlation with rising MPXD cases, although the trend predicts peak values while the overall trend increases. This underscores the importance of immediate and appropriate preventive measures (timely preparedness and proactive control strategies) with utmost priority against MPXD including awareness-raising programs, the discovery, and formulation of effective vaccine candidate(s), prophylaxis and therapeutic regimes, and management strategies.