Correlation between monkeypox viral load and infectious virus in clinical specimens

Clinical presentation, viral shedding, and neutralizing antibody responses of mpox cases in South Korea: Single center experience

BACKGROUND

A global mpox outbreak occurred in 2022, and a domestic outbreak started in South Korea in April 2023. This study aimed to evaluate the clinical characteristics, viral shedding, and immune response of mpox in South Korea.

METHODS

Patients hospitalized with mpox in the National Medical Center between September 2022 and June 2023 were included in this study. Oropharyngeal (OP), anogenital lesion (AL), and skin lesion (SL) swabs and blood samples were collected, and monkeypox virus (MPXV) DNA using real-time polymerase chain reaction (RT-PCR) and culture assays were performed. Neutralizing antibodies (NAbs) against MPXV A.2.1, B.1.1, and B.1.3 were detected using plaque reduction neutralization tests.

RESULTS

Eighteen patients were enrolled, of whom 17 (94.4 %) were male, with a median (IQR) age of 32.5 (24-51) years. While nine (50 %) were HIV-infected individuals, none of them revealed CD4+ counts less than 200 cells/μL. MPXV DNA was detected in 87.3 % and 82.7 % of patient's ALs and SLs, respectively, until 2 weeks after symptom onset. While MPXV was isolated for up to 15 days in all three sample types, the culture positivity decreased to 53.8 % and 42.9 % in ALs and SLs after 10 days, respectively, and 28.6 % and 22.2 %, respectively, after 2 weeks from symptom onset. The NAb titers against MPXV A.2.1 were significantly lower than those against B.1.1 and B.1.3.

CONCLUSIONS

Infectious MPXV was isolated from various anatomical sites up to 15 days after symptom onset. The MPXV NAb response was varied among different lineages, and this implies limited cross-lineage protection.

Profiling of viral load, antibody and inflammatory response of people with monkeypox during hospitalization: a prospective longitudinal cohort study in China

BACKGROUND

The dynamics of viral shedding and the specific humoral response against monkeypox virus (MPXV) have not been well characterized in patients across their disease course during hospitalisation. The aim of this study was to determine the viral load and the levels of antibodies against MPXV using longitudinal paired-collected samples from hospitalized patients.

METHODS

Patients who were hospitalised with mpox were recruited at Beijing Ditan Hospital Capital Medical University in China between June 2 and September 23, 2023. Paired samples, including samples from skin lesions, the oropharynx, saliva, faeces, urine, plasma, and serum, were serially collected at days 1, 3, 7, and 14 after admission until discharge. Not all of the patients had samples obtained at all of the timepoints. All the samples were analysed via quantitative PCR. Virus isolation was performed by using clinical samples and Vero cells. The presence of IgM, IgA, IgG, and neutralising antibodies (NAbs) against MPXV was evaluated. The first collected plasma sample was taken when the patient was hospitalised, and the levels of cytokines and chemokines were measured in the sample. The demographic data, smallpox vaccination status, history of known exposure to MPVX, HIV status and other clinical data were collected using a standard case report form.

FINDINGS

A total of 510 specimens were serially collected from 39 recruited people with mpox. Among all the samples, the skin lesions had the highest viral DNA detection rates and viral loads, and the saliva samples had the second highest rates and viral loads. One day before discharge, 85% of the dry scrabs (median Ct 28.2, range 19.0-38.3) and 70% of the saliva samples (median Ct 32.4, range 24.5-38.1) were positive for viral DNA, Of which, 23.1% of dry scrabs were positive in viral culture. The rate of viral DNA detection in the oropharyngeal, saliva, and faecal samples decreased with time, while the rates in the plasma, serum, and urine samples increased quickly before 10 days post symptom onset (PSO). The median days of appearance of MPXV-IgM, MPXV-IgA, MPXV-IgG, and NAb were at 8 (interquartile range [IQR] 7-9), 9 (7-10), 12 (9-15), and 12 (9-15) PSO, respectively. The IgM, IgA, IgG, and NAb titres increased with time. Between days 11 and 21 PSO, the NAb titres were lower in people living with HIV (PWH) than in people living without HIV (PWOH). Increased NAb titres were associated with decreased viral loads in the saliva (r = 0.28, p = 0.025), faeces (r = 0.35, p = 0.021), plasma (r = 0.30, p = 0.0044), and serum samples (r = 0.37, p = 0.001). Compared with PWOH, PWH had higher plasma levels of MIP-1α, MIP-1β, G-CSF, IL-4, and FGF-basic.

INTERPRETATION

The high positive viral culture rate of clinical samples of patients when they are discharged from the hospital indicates that effective public health management strategies are needed for people with mpox. The low NAb titres and high levels of cytokines in PWH shows that earlier treatment is needed to control inflammation in high-risk populations.

FUNDING

National Natural Science Foundation of China, Chinese Academy of Medical Sciences, Fundamental Research Funds for the Central Universities for Peking Union Medical College, National Key R&D Program of China.

Applying improved ddPCR to reliable quantification of MPXV in clinical settings

Monkeypox virus (MPXV) poses a global health threat. Droplet digital PCR (ddPCR) holds potential as an accurate diagnostic tool for clinical microbiology. However, there is limited literature on the applicability of ddPCR in clinical settings. In this study, the clinical features of patients with MPXV during the initial outbreak in China in June 2023 were reviewed, and an optimized ddPCR method with dilution and/or inhibitor removal was developed to enhance MPXV detection efficiency. Eighty-two MPXV samples were tested from nine different clinical specimen types, including feces, urine, pharyngeal swabs, anal swabs, saliva, herpes fluid, crust, and semen, and the viral load of each specimen was quantified. A comparative analysis was performed with qPCR to assess sensitivity and specificity and to investigate the characteristics of MPXV infection by analyzing viral loads in different clinical specimens. Consequently, common pharyngeal and gastrointestinal symptoms were observed in patients with MPXV. The optimized ddPCR method demonstrated relatively high sensitivity for MPXV quantification in the clinical materials, with a limit of detection of 0.1 copies/μL. This was particularly evident in low-concentration samples like whole blood, semen, and urine. The optimized ddPCR demonstrated greater detection accuracy compared with normal ddPCR and qPCR, with an area under the curve (AUC) of 0.939. Except for crust samples, viral loads in the specimens gradually decreased as the disease progressed. Virus levels in feces and anal swabs kept a high detection rate at each stage of post-symptom onset, and feces and anal swabs samples may be suitable for clinical diagnosis and continuous monitoring of MPXV.

IMPORTANCE

The ddPCR technique proved to be a sensitive and valuable tool for accurately quantifying MPXV viral loads in various clinical specimen types. The findings provided valuable insights into the necessary pre-treatment protocols for MPXV diagnosis in ddPCR detection and the potentially suitable sample types for collection. Therefore, such results can aid in comprehending the potential characteristics of MPXV infection and the usage of ddPCR in clinical settings.

MPXV DNA kinetics in bloodstream and other body fluids samples

Since spring 2022, the global epidemiology of the monkeypox virus (MPXV) has changed. The unprecedented increase of human clade II MPXV cases worldwide heightened concerns about this emerging zoonotic disease. We analysed the positivity rates, viral loads, infectiousness, and persistence of MPXV DNA for up to 4 months in several biological samples from 89 MPXV-confirmed cases. Our data showed that viral loads and positivity rates were higher during the first two weeks of symptoms for all sample types. Amongst no-skin-samples, respiratory specimens showed higher MPXV DNA levels and median time until viral clearance, suggesting their usefulness in supporting MPXV diagnosis, investigating asymptomatic patients, and monitoring viral shedding. Infectious virus was cultured from respiratory samples, semen, and stools, with high viral loads and collected within the first 10 days. Notably, only one saliva and one semen were found positive for viral DNA after 71 and 31 days from symptoms, respectively. The focus on bloodstream samples showed the best testing sensitivity in plasma, reporting the overall highest MPXV DNA detection rate and viral loads during the 3-week follow-up as compared to serum and whole-blood. The data here presented can be useful for MPXV diagnostics and a better understanding of the potential alternative routes of its onward transmission.

Mpox virus DNA detection in different clinical specimens: tertiary-level laboratory experience, Bosnia and Herzegovina, 2022

Mpox virus (MPXV) infection is difficult to distinguish from other (non-)infectious diseases. The etiology of rash can be differentiated by real-time polymerase chain reaction (rtPCR) on different types of samples. The study aims to provide experience with emerging MPXV diagnostics in a tertiary-level laboratory in Bosnia and Herzegovina. From July-December 2022, a total of 18 mpox suspected persons were tested. MPXV infection was confirmed by rtPCR in 10/18 (55.56 %) persons. The number of cases reached a peak in October 2022. The lowest median Crossing point (Cp) (x̄ = 29.76) was obtained from a swab of skin lesions in a viral transport medium (VTM). Evaluating the Cp values for the 7/9 mpox cases from whom paired swab samples from different anatomic sites were collected, higher positivity of skin lesion swabs in VTM was observed. In conclusion, our data highlighted the confirmatory role of rtPCR in the diagnosis of MPXV in skin lesion samples.

Ensuring accuracy in the development and application of nucleic acid amplification tests (NAATs) for infectious disease

Diagnostic tests were heralded as crucial during the Coronavirus disease (COVID-19) pandemic with most of the key methods using bioanalytical approaches that detected larger molecules (RNA, protein antigens or antibodies) rather than conventional clinical biochemical techniques. Nucleic Acid Amplification Tests (NAATs), like the Polymerase Chain Reaction (PCR), and other molecular methods, like sequencing (that often work in combination with NAATs), were essential to the diagnosis and management during COVID-19. This was exemplified both early in the pandemic but also later on, following the emergence of new genetic SARS-CoV-2 variants. The 100 day mission to respond to future pandemic threats highlights the need for effective diagnostics, therapeutics and vaccines. Of the three, diagnostics represents the first opportunity to manage infectious diseases while also being the most poorly supported in terms of the infrastructure needed to demonstrate effectiveness. Where performance targets exist, they are not well served by consensus on how to demonstrate they are being met; this includes analytical factors such as limit of detection (LOD) false positive results as well as how to approach clinical evaluation. The selection of gold standards or use of epidemiological factors such as predictive value, reference ranges or clinical thresholds are seldom correctly considered. The attention placed on molecular diagnostic tests during COVID-19 illustrates important considerations and assumptions on the use of these methods for infectious disease diagnosis and beyond. In this manuscript, we discuss state-of-the-art approaches to diagnostic evaluation and explore how they may be better tailored to diagnostic techniques like NAATs to maximise the impact of these highly versatile bioanalytical tools, both generally and during future outbreaks.

Longitudinal viral shedding and antibody response characteristics of men with acute infection of monkeypox virus: a prospective cohort study

Understanding of infection dynamics is important for public health measures against monkeypox virus (MPXV) infection. Herein, samples from multiple body sites and environmental fomites of 77 acute MPXV infections (HIV co-infection: N = 42) were collected every two to three days and used for detection of MPXV DNA, surface protein specific antibodies and neutralizing titers. Skin lesions show 100% positivity rate of MPXV DNA, followed by rectum (88.16%), saliva (83.78%) and oropharynx (78.95%). Positivity rate of oropharynx decreases rapidly after 7 days post symptom onset (d.p.o), while the rectum and saliva maintain a positivity rate similar to skin lesions. Viral dynamics are similar among skin lesions, saliva and oropharynx, with a peak at about 6 d.p.o. In contrast, viral levels in the rectum peak at the beginning of symptom onset and decrease rapidly thereafter. 52.66% of environmental fomite swabs are positive for MPXV DNA, with highest positivity rate (69.89%) from air-conditioning air outlets. High seropositivity against A29L (100%) and H3L (94.74%) are detected, while a correlation between IgG endpoint titers and neutralizing titers is only found for A29L. Most indexes are similar between HIV and Non-HIV participants, while HIV and rectitis are associated with higher viral loads in rectum.

Dynamics of viral DNA shedding and culture viral DNA positivity in different clinical samples collected during the 2022 mpox outbreak in Lombardy, Italy

BACKGROUND

Mpox virus (MPXV) has recently spread outside of sub-Saharan Africa. This large multicentre study was conducted in Lombardy, the most densely populated Italian region accounting for more than 40% of Italian cases. The present study aims to: i) evaluate the presence and the shedding duration of MPXV DNA in different body compartments correlating the MPXV viability with the time to onset of symptoms; ii) provide evidence of MPXV persistence in different body compartment as a source of infection and iii) characterize the MPXV evolution by whole genome sequencing (WGS) during the outbreak occurred in Italy.

MATERIAL AND METHODS

The study included 353 patients with a laboratory-confirmed diagnosis of MPXV infection screened in several clinical specimens in the period May 24th - September 1st, 2022. Viral isolation was attempted from different biological matrices and complete genome sequencing was performed for 61 MPXV strains.

RESULTS

MPXV DNA detection was more frequent in the skin (94.4%) with the longest median time of viral clearance (16 days). The actively-replicating virus in cell culture was obtained for 123/377 (32.6%) samples with a significant higher viral quantity on isolation positive samples (20 vs 31, p < 0.001). The phylogenetic analysis highlighted the high genetic identity of the MPXV strains collected, both globally and within the Lombardy region.

CONCLUSION

Skin lesion is gold standard material and the high viral load and the actively-replicating virus observed in genital sites confirms that sexual contact plays a key role in the viral transmission.

Sexual Exposures Associated With Mpox Infection: California, November 2022 to June 2023

BACKGROUND

Exposures associated with mpox infection remain imperfectly understood.

METHODS

We conducted a case-control study enrolling participants who received molecular tests for mpox/orthopoxvirus in California from November 2022 through June 2023. We collected data on behaviors during a 21-day risk period before symptom onset or testing among mpox case patients and test-negative controls.

RESULTS

Thirteen of 54 case patients (24.1%) and 5 of 117 controls (4.3%) reported sexual exposure to individuals they identified as potential mpox case patients ("index contacts"; odds ratio [OR], 7.7 [95% confidence interval (CI), 2.5-19.3] relative to individuals who did not report exposure to potential mpox case patients). Among these participants, 10 of 13 case patients (76.9%) and 2 of 5 controls (40.0%) reported that their index contacts were not experiencing symptoms visible to participants during sex (OR, 14.9 [95% CI, 3.6-101.8]). Only 3 of 54 case patients (5.6%) reported exposure to symptomatic index contacts. Case patients reported more anal/vaginal sex partners than did controls (adjusted OR, 2.2 [95% CI, 1.0-4.8] for 2-3 partners and 3.8 [1.7-8.8] for ≥4 partners). Male case patients with penile lesions more commonly reported insertive anal/vaginal sex than those without penile lesions (adjusted OR, 9.3 [95% CI, 1.6-54.8]). Case patients with anorectal lesions more commonly reported receptive anal sex than those without anorectal lesions (adjusted OR, 14.4 [95% CI, 1.0-207.3]).

CONCLUSIONS

Sexual exposure to contacts known or suspected to have experienced mpox was associated with increased risk of infection, often when index contacts lacked apparent symptoms. Exposure to more sex partners, including those whom participants did not identify as index contacts, was associated with increased risk of infection in a site-specific manner. While participants' assessment of symptoms in partners may be imperfect, these findings suggest that individuals without visibly prominent mpox symptoms transmit infection.

Inadvertent Platelet Transfusion from Monkeypox Virus-Infected Donor to Recipient, Thailand, 2023

In Thailand, platelet product from a blood donor was transfused to a recipient who had dengue. Two days later, the donor was confirmed to have monkeypox virus infection. Monkeypox virus DNA was undetectable in recipient specimens up to 2 weeks after transfusion. The recipient remained asymptomatic at 4 weeks of monitoring.

Update on Mpox: What the Primary Care Clinician Should Know

Mpox is a viral infection, which primarily caused sporadic outbreaks in West and Central Africa until causing a global epidemic in 2022. The disease has disproportionately affected people with human immunodeficiency virus and men who have sex with men. Transmission is through close physical contact, including sexual contact. Infection presents with a characteristic rash, with frequent anogenital involvement-polymerase chain reaction of skin lesions is diagnostic. Vaccination is available for primary prevention and postexposure prophylaxis. Treatment consists of supportive care, with antiviral medications available via clinical trials and/or for patients with severe disease.

Case report: atypical presentation of mpox with massive hematochezia and prolonged viral shedding despite tecovirimat treatment

BACKGROUND

The outbreak of mpox that occurred between 2022 and 2023 is primarily being transmitted through sexual contact. As of now, there is no consensus on the recommended duration of isolation to prevent sexual transmission of the virus. Moreover, this particular mpox outbreak has presented with distinct complications in comparison to previous occurrences. In this report, we present a case involving severe rectal bleeding from an ulcer in a mpox patient with a history of engaging in receptive sexual contact.

CASE PRESENTATION

A 30-year-old Korean man presented at the hospital with complaints of fever, multiple skin lesions, and anal pain. Monkeypox virus polymerase chain reaction (PCR) results were positive for skin lesions on the penis and wrist. The patient received a 12-day course of tecovirimat due to anal symptoms and perianal skin lesions. Following isolation for 12 days and after all skin scabs had naturally fallen off, with no new skin lesions emerging for a consecutive 48 hours-conforming to the criteria of the Korean Disease Control and Prevention Agency-the patient was discharged. However, 1 day after discharge, the patient returned to the hospital due to hematochezia. His hemoglobin level had significantly dropped from 14.0 g/dL to 8.2 g/dL. Sigmoidoscopy unveiled a sizable rectal ulceration with exposed blood vessels, prompting the application of hemostasis through metal clipping. Subsequent monkeypox virus real-time PCR conducted on rectal tissue and swabs yielded positive results (with cycle threshold values of 28.48 and 31.23, respectively). An abdominal CT scan exposed a perirectal abscess, for which ampicillin-sulbactam was administered.

CONCLUSION

This case underscores the importance of monitoring for bleeding complications and confirming the resolution of rectal lesions before discharging patients from isolation, particularly in cases where patients have a history of engaging in receptive sexual contact with men or are presenting with anal symptoms.

Longitudinal Analysis of Mpox Virus DNA Detectability From Multiple Specimen Types During Acute Illness: A Cohort Study

Background

Longitudinal data on the detectability of monkeypox virus (MPXV) genetic material in different specimen types are scarce.

Methods

We describe MPXV-specific polymerase chain reaction (PCR) results from adults with confirmed mpox infection from Toronto, Canada, including a cohort undergoing weekly collection of specimens from multiple anatomic sites until 1 week after skin lesions had fully healed. We quantified the time from symptom onset to resolution of detectable viral DNA (computed tomography [Ct] ≥ 35) by modeling exponential decay in Ct value as a function of illness day for each site, censoring at the time of tecovirimat initiation.

Results

Among 64 men who have sex with men, the median (interquartile range [IQR]) age was 39 (32.75-45.25) years, and 49% had HIV. Twenty received tecovirimat. Viral DNA was detectable (Ct < 35) at baseline in 74% of genital/buttock/perianal skin swabs, 56% of other skin swabs, 44% of rectal swabs, 37% of throat swabs, 27% of urine, 26% of nasopharyngeal swabs, and 8% of semen samples. The median time to resolution of detectable DNA (IQR) was longest for genital/buttock/perianal skin and other skin swabs at 30.0 (23.0-47.9) and 22.4 (16.6-29.4) days, respectively, and shortest for nasopharyngeal swabs and semen at 0 (0-12.1) and 0 (0-0) days, respectively. We did not observe an effect of tecovirimat on the rate of decay in viral DNA detectability in any specimen type (all P > .05).

Conclusions

MPXV DNA detectability varies by specimen type and persists for over 3-4 weeks in skin specimens. The rate of decay did not differ by tecovirimat use in this nonrandomized study.

Detecting Mpox Cases Through Wastewater Surveillance - United States, August 2022-May 2023

In October 2022, CDC's National Wastewater Surveillance System began routine testing of U.S. wastewater for Monkeypox virus. Wastewater surveillance sensitivity, positive predictive value (PPV), and negative predictive value (NPV) for Monkeypox virus were evaluated by comparing wastewater detections (Monkeypox virus detected versus not detected) to numbers of persons with mpox in a county who were shedding virus. Case ascertainment was assumed to be complete, and persons with mpox were assumed to shed virus for 25 days after symptom onset. A total of 281 cases and 3,492 wastewater samples from 89 sites in 26 counties were included in the analysis. Wastewater surveillance in a single week, from samples representing thousands to millions of persons, had a sensitivity of 32% for detecting one or more persons shedding Monkeypox virus, 49% for detecting five or more persons shedding virus, and 77% for detecting 15 or more persons shedding virus. Weekly PPV and NPV for detecting persons shedding Monkeypox virus in a county were 62% and 80%, respectively. An absence of detections in counties with wastewater surveillance signified a high probability that a large number of cases were not present. Results can help to guide the public health response to Monkeypox virus wastewater detections. A single, isolated detection likely warrants a limited public health response. An absence of detections, in combination with no reported cases, can give public health officials greater confidence that no cases are present. Wastewater surveillance can serve as a useful complement to case surveillance for guiding the public health response to an mpox outbreak.

Plausible reasons for the resurgence of Mpox (formerly Monkeypox): an overview

Poxviruses are large and diversified viruses that cause an emerging zoonotic disease known as monkeypox (mpox). In the past, mpox predominated primarily in the rural rainforests of Central and West Africa. Recently, the exportation of mpoxv from Africa to other continents has been progressively reported. However, the lack of travel history to Africa in most of the currently reported cases in 2022 promotes the sign of changing epidemiology of this disease. Concerns over the geographic distribution and continued resurgence of mpox is growing. In this review, we addressed the geographic distribution, transmission, reasons for the resurgence of mpox, and vaccination. Although the precise cause of the resurgence in mpox cases is mostly unknown, several suggested factors are believed to be waning immunity, accumulation of unvaccinated people, ecological conditions, risk behaviors of men who have sex with men, and genetic evolution.

Mpox DNA clearance in semen over 6-month follow-up

Sexual intercourse is a well-established way of transmission of mpox infection. However, it is still uncertain whether semen may represent a viral reservoir. The aim of the study was to evaluate the clearance of viral DNA in semen samples from individuals diagnosed with mpox infection over 6-month follow-up. This prospective, observational, single-center study was conducted at IRCCS San Raffaele Scientific Institute, Milan, Italy, between May and October 2022 in 140 individuals who attended Sexual Health Clinic and diagnosed with mpox infection. Semen samples were collected and analyzed by real-time polymerase chain reaction assays. The baseline collection was performed in 64 (46%) of 140 men diagnosed with mpox infection. The viral DNA was detected in 43 (67%) with median cycle threshold (Ct) 34 (interquartile range [IQR] 31-36). The research was repeated in 32 (74%) and viral DNA clearance was observed in all within 6 months in a median time of 10.5 days (IQR 7-33). Viral clearance occurred in all tested individuals, mostly within 2 weeks since the first positive test. These findings suggest a transient presence of viral DNA in semen and do not support the hypothesis of reservoir. More studies on mpox DNA detection in semen with viral culture and extended follow-up are needed.

Development and validation of a nanoplate-based digital PCR assay for absolute MPXV quantification

Quantification of mpox virus (MPXV) across different human body anatomical sites can provide insights about the most likely transmission routes, so methods able to release absolute and exact quantitative values of MPXV DNA are crucial. Here, we optimized a new QIAcuity digital PCR (dPCR) protocol for the detection and quantification of MPXV DNA in clinical samples and assessed the performance of the assay by comparing the results obtained in 144 biological samples with those resulting from the use of an in-house real-time PCR (qPCR). Overall, the concordance between the two assays was 95%, with samples identified concordantly as MPXV DNA positive and having a mean number of copies per μl of 1708 (95% CI: 107-2830 copies/μl). The remaining samples gave discordant results, with 5 out of 7 detected with the QIAcuity dPCR assay but not with the in-house qPCR. MPXV DNA levels measured by QIAcuity dPCR were strongly correlated with the Ct values detected by in-house qPCR and with those detected by another dPCR assay previously developed in our laboratories. The QIAcuity dPCR assay may be a robust and easy-to-perform method for MPXV DNA quantification in several biological samples.

Monitoring Monkeypox: Safeguarding Global Health through Rapid Response and Global Surveillance

Monkeypox, a viral zoonotic disease, has emerged as a significant global threat in recent years. This review focuses on the importance of global monitoring and rapid response to monkeypox outbreaks. The unpredictable nature of monkeypox transmissions, its potential for human-to-human spread, and its high morbidity rate underscore the necessity for proactive surveillance systems. By analyzing the existing literature, including recent outbreaks, this review highlights the critical role of global surveillance in detecting, containing, and preventing the further spread of monkeypox. It also emphasizes the need for enhanced international collaboration, data sharing, and real-time information exchange to effectively respond to monkeypox outbreaks as a global health concern. Furthermore, this review discusses the challenges and opportunities of implementing robust surveillance strategies, including the use of advanced diagnostic tools and technologies. Ultimately, these findings underscore the urgency of establishing a comprehensive global monitoring framework for monkeypox, enabling early detection, prompt response, and effective control measures to protect public health worldwide.

Monkeypox presenting as a chancre-like rash: A case report

BACKGROUND

Since May 2022, outbreaks of monkeypox have occurred in many countries around the world, and several cases have been reported in China.

CASE SUMMARY

A 38-year-old man presented with a small, painless, shallow ulcer on the coronary groove for 8 d. One day after the rash appeared, the patient developed inguinal lymphadenopathy with fever. The patient had a history of male-male sexual activity and denied a recent history of travel abroad. Monkeypox virus was detected by quantitative polymerase chain reaction from the rash site and throat swab. Based on the epidemiological history, clinical manifestations and nucleic acid test results, the patient was diagnosed with monkeypox.

CONCLUSION

Monkeypox is an emerging infectious disease in China. Monkeypox presenting as a chancre-like rash is easily misdiagnosed. Diagnosis can be made based on exposure history, clinical manifestations and nucleic acid test results.

Viral load dynamics and shedding kinetics of mpox infection: a systematic review and meta-analysis

BACKGROUND

Viral load dynamics and shedding kinetics are critical factors for studying infectious diseases. However, evidence on the viral dynamics of mpox remains limited and inconclusive. Thus, we aimed to provide a comprehensive understanding of the viral load and viability of the re-emerged mpox virus since 2022.

METHODS

For this systematic review and meta-analysis, we searched PubMed/MEDLINE, Embase and Google Scholar for published articles that are related to mpox viral dynamics up to April 2023.

RESULTS

From 19 studies, 880 samples and 1477 specimens were collected. The pooled median Ct values appeared in the following order: skin lesion [Ct value 21.7 (IQR 17.8-25.5)], anorectal [22.3 (16.9-27.6)], saliva [25.9 (22.5-31.1)], oral [29.0 (24.5-32.8)], semen [29.6 (25.9-33.4)], urine [30.5 (24.6-36.4)], pharyngeal [31.9 (26.5-37.3)], urethra [33.0 (28.0-35.0)] and blood [33.2 (30.4-36.1)]. People living with human immunodeficiency virus (HIV) have a lower Ct value in the skin [skin HIV+, 19.2 (18.3-20.0) vs skin HIV-, 25.4 (21.2-29.0)]. From the Ct values and test day since symptom onset, we identified temporal trends of viral load for each specimen type. Changes in the trend were observed at 4 days in saliva, 5 days in blood, 6 days in skin, 7 days in anorectal, urine, semen and pharyngeal and 8 days in the urethra. We determined optimal Ct cutoff values for anorectal (34.0), saliva (27.7) and urethra (33.0) specimens, where a Ct value above each cutoff suggests minimal viral viability. Using these cutoff values, we derived the duration of viable viral isolation in each specific specimen type (anorectal 19 days, saliva 14 days and urethra 14 days).

CONCLUSION

Skin lesion, anorectal and saliva samples contained the highest viral load. The peak viral load manifests within 4-8 days after symptom onset, and viable virus detection was presumed to cease within 14-19 days from symptom onset in anorectal, saliva and urethral samples.

A Case of Severe Mpox Complicated with Streptococcus pyogenes Sepsis in a Patient with HIV Infection

Since May 2022, a global outbreak of human Mpox has rapidly spread in non-endemic countries. We report a case of a 34-year-old man admitted to hospital for a six-day history of fever associated with vesiculo-pustular rash involving the face, limbs, trunk and perianal region, lymphadenopathy and severe proctitis and pharyngitis. He was HIV-positive and virologically suppressed by stable antiretroviral therapy. On admission, Mpox virus-specific RT-PCR was positive from multiple samples. Additionally, blood cultures yielded Streptococcus pyogenes, prompting a 14-day-course of penicillin G and clindamycin. Due to the worsening of proctitis along with right ocular mucosa involvement, tecovirimat treatment was started with a rapid improvement in both skin and mucosal involvement. The patient was discharged after 21 days of hospitalization and the complete clinical resolution occurred 38 days after symptom onset. This is a case of Mpox with extensive multi-mucosal (ocular, pharyngeal and rectal) and cutaneous extension and S. pyogenes bacteraemia probably related to bacterial translocation from the skin or oral cavity that was eased by Mpox lesions/inflammation. The HIVinfection, although well controlled by antiretroviral therapy, could have played a role in the severe course of Mpox, suggesting the importance of a prompt antiviral treatment in HIV-positive patients.

Intra- and interhost genomic diversity of monkeypox virus

The impact and frequency of infectious disease outbreaks demonstrate the need for timely genomic surveillance to inform public health responses. In the largest known outbreak of mpox, genomic surveillance efforts have primarily focused on high-incidence nations in Europe and the Americas, with a paucity of data from South-East Asia and the Western Pacific. Here we analyzed 102 monkeypox virus (MPXV) genomes sampled from 56 individuals in Melbourne, Australia. All genomes fell within the 2022 MPXV outbreak lineage (B.1), with likely onward local transmission detected. We observed within-host diversity and instances of co-infection, and highlight further examples of structural variation and apolipoprotein B editing complex-driven micro-evolution in the current MPXV outbreak. Updating our understanding of MPXV emergence and diversification will inform public health measures and enable monitoring of the virus' evolutionary trajectory throughout the mpox outbreak.

Viral Loads in Skin Samples of Patients with Monkeypox Virus Infection: A Systematic Review and Meta-Analysis

Despite monkeypox (mpox) being a public health emergency, there is limited knowledge about the risk of infectivity from skin viral loads during mpox infection. Thus, the aim of this study was to estimate cutaneous viral loads among mpox patients globally. Several databases, including Cochrane, EBSCOHost, EMBASE, ProQuest, PubMed, Scopus, and Web of Science, and preprint servers were searched concerning skin mpox viral loads in confirmed mpox subjects. In this systematic review and meta-analysis, a total of 331 articles were initially screened after the removal of duplicate entries. A total of nine articles were included in the systematic review and meta-analysis for the overall estimation of viral loads (Ct) using a random-effect model. The pooled cutaneous mpox viral load (lower Ct) was 21.71 (95% CI: 20.68-22.75) with a majority of positivity rates being 100%, highlighting a higher infectivity risk from skin lesions. The current results strongly support that skin mpox viral loads may be a dominant source of rapid transmission during current multi-national outbreaks. This important finding can help in constructing useful measures in relevant health policy.

CROI 2023: Epidemiology, Diagnosis, and Management of MPox

The 2023 Conference on Retroviruses and Opportunistic Infections (CROI) emphasized emerging infectious diseases such as COVID-19 and mpox. Despite emerging from countries in which it was endemic only 9 months before the conference, mpox was well covered, with more than 60 presentations addressing various topics. There was a focus on the rapid development and implementation of tests to reduce the time to diagnosis, as well as multiplex panels to increase the accuracy of differential diagnosis. Presenters also highlighted the ability to diagnose mpox from multiple compartments, such as with rectal and pharyngeal swabs, and provided crucial information on the duration of positivity that may impact isolation requirements. Clinical experiences were described, including risk factors for severe disease and syndemic management. High rates of concomitant sexually transmitted infection (STI) were reported. Finally, prevention was a key topic, with presenters pointing to the contributions of individual behavioral changes and vaccine efficacy to reducing new cases.