Monkeypox Virus Detection in Different Clinical Specimen Types

Preparing for Mpox Resurgence: Surveillance Lessons From Outbreaks in Toronto, Canada

BACKGROUND

With many global jurisdictions, Toronto, Canada, experienced an mpox outbreak in spring/summer 2022. Cases declined following implementation of a large vaccination campaign. A surge in early 2023 led to speculation that asymptomatic and/or undetected local transmission was occurring in the city.

METHODS

Mpox cases and positive laboratory results are reported to Toronto Public Health. Epidemic curves and descriptive risk factor summaries for the 2022 and 2023 outbreaks were generated. First- and second-dose vaccination was monitored. Mpox virus wastewater surveillance and whole genome sequencing were conducted to generate hypotheses about the source of the 2023 resurgence.

RESULTS

An overall 515 cases were reported in spring/summer 2022 and 17 in the 2022-2023 resurgence. Wastewater data correlated with the timing of cases. Whole genome sequencing showed that 2022-2023 cases were distinct from 2022 cases and closer to sequences from another country, suggesting a new importation as a source. At the start of the resurgence, approximately 16% of first-dose vaccine recipients had completed their second dose.

CONCLUSIONS

This investigation demonstrates the importance of ongoing surveillance and preparedness for mpox outbreaks. Undetected local transmission was not a likely source of the 2022-2023 resurgence. Ongoing preexposure vaccine promotion remains important to mitigate disease burden.

Evaluation of 5 Polymerase Chain Reaction Assays for the Detection of Mpox Virus

BACKGROUND

In 2022, the global dissemination of mpox virus (MPXV) outside endemic regions prompted the expansion of diagnostic testing worldwide. This study assesses the performance characteristics of 5 real-time polymerase chain reaction (PCR) assays in detecting MPXV during the 2022 outbreak.

METHODS

Clinical specimens collected from patients across Ontario, Canada, were tested on the following assays: RealStar Orthopoxyvirus PCR and FlexStar Monkeypox virus PCR (Altona Diagnostics), Novaplex MPXV (Seegene), VIASURE Monkeypox virus Real Time PCR Reagents (CerTest Biotec), and a laboratory-developed test. Positive percent agreement (PPA), negative percent agreement (NPA), relative limit of detection (LOD), and precision were evaluated and MPXV lineages were determined using an amplicon-based whole-genome sequencing (WGS) assay.

RESULTS

Swabs were collected from various anatomic sites (65 positive and 30 negative). All assays demonstrated 100% NPA (95% confidence interval, 88.4%/88.1%-100.0%), with PPA ranging from 92.2% (82.7%-97.4%) to 96.9% (89.3%-99.6%). LOD and precision were comparable across assays, with coefficient of variations <3%. WGS analysis identified 6 lineages, all belonging to subclade IIb.

CONCLUSIONS

The assays exhibited excellent PPA, NPA, LOD, and precision. Ongoing performance monitoring is essential to detect assay escape mutants and ensure universal detection of evolving MPXV strains.

How the Orthodox Features of Orthopoxviruses Led to an Unorthodox Mpox Outbreak: What We've Learned, and What We Still Need to Understand

Orthopoxviruses have repeatedly confounded expectations in terms of the clinical illness they cause and their patterns of spread. Monkeypox virus (MPXV), originally characterized in the late 1950s during outbreaks among captive primates, has been recognized since the 1970s to cause human disease (mpox) in West and Central Africa, where interhuman transmission has largely been associated with nonsexual, close physical contact. In May 2022, a focus of MPXV transmission was detected, spreading among international networks of gay, bisexual, and other men who have sex with men. The outbreak grew in both size and geographic scope, testing the strength of preparedness tools and public health science alike. In this article we consider what was known about mpox before the 2022 outbreak, what we learned about mpox during the outbreak, and what continued research is needed to ensure that the global public health community can detect, and halt further spread of this disease threat.

Targeted amplification-based whole genome sequencing of Monkeypox virus in clinical specimens

IMPORTANCE

We present a protocol to efficiently sequence genomes of the MPXV-causing mpox. This enables researchers and public health agencies to acquire high-quality genomic data using a rapid and cost-effective approach. Genomic data can be used to conduct surveillance and investigate mpox outbreaks. We present 91 mpox genomes that show the diversity of the 2022 mpox outbreak in Ontario, Canada.

Extraction-free LAMP assays for generic detection of Old World Orthopoxviruses and specific detection of Mpox virus

Mpox is a neglected zoonotic disease endemic in West and Central Africa. The Mpox outbreak with more than 90,000 cases worldwide since 2022 generated great concern about future outbreaks and highlighted the need for a simple and rapid diagnostic test. The Mpox virus, MPV, is a member of the Orthopoxvirus (OPV) genus that also contains other pathogenic viruses including variola virus, vaccinia virus, camelpox virus, and cowpox virus. Phylogenomic analysis of 200 OPV genomes identified 10 distinct phylogroups with the New World OPVs placed on a very long branch distant from the Old World OPVs. Isolates derived from infected humans were found to be distributed across multiple phylogroups interspersed with isolates from animal sources, indicating the zoonotic potential of these viruses. In this study, we developed a simple and sensitive colorimetric LAMP assay for generic detection of Old World OPVs. We also developed an MPV-specific probe that differentiates MPV from other OPVs in the N1R LAMP assay. In addition, we described an extraction-free protocol for use directly with swab eluates in LAMP assays, thereby eliminating the time and resources needed to extract DNA from the sample. Our direct LAMP assays are well-suited for low-resource settings and provide a valuable tool for rapid and scalable diagnosis and surveillance of OPVs and MPV.

Insights on monkeypox disease and its recent outbreak with evidence of nonsynonymous missense mutation

The 2022 monkeypox outbreak has created a new global health threat and pandemic. Monkeypox virus is a descendant of the genus Orthopoxvirus, producing a febrile skin rash disease in humans. Monkeypox is zoonotic transmitted and transmitted from human to human in several ways. Even though this disease is self-limited, it creates important community health worries due to its inconvenience and widespread complications. Herein, we discussed the up-to-date current situation of monkeypox regarding its epidemiology, clinical manifestations, current in-use therapeutics, necessary protective measures, and response to potential occurrences considering the recent pandemic. Also, in this review, a comparative genomic analysis of the recent circulating strains that have been recovered from various countries including, Egypt, USA, Spain, Japan and South Africa has been investigated.

Evidence of Mpox Virus Infection Among Persons Without Characteristic Lesions or Rash Presenting for First Dose of JYNNEOS Vaccine-District of Columbia, August 2022

We assessed mpox virus prevalence in blood, pharyngeal, and rectal specimens among persons without characteristic rash presenting for JYNNEOS vaccine. Our data indicate that the utility of risk-based screening for mpox in persons without skin lesions or rash via pharyngeal swabs, rectal swabs, and/or blood is likely limited.

Detecting, Quantifying, and Isolating Monkeypox Virus in Suspected Cases, Spain

When a monkeypox virus outbreak began in several parts of the world in May 2022, timely and accurate diagnosis became mandatory. In our laboratory, a real-time quantitative PCR was designed and evaluated in several patient samples and compared with isolation results. Genomic viral load was related to virus viability.

Prevalence of mpox viral DNA in cutaneous specimens of monkeypox-infected patients: a systematic review and meta-analysis

Background

Human monkeypox (mpox) disease is a multicountry outbreak driven by human-human transmission which has resulted in an international public health emergency. However, there is limited evidence on the positivity rate of skin lesions for mpox viral DNA. We aim to fill this gap by estimating the pooled positivity rate of skin samples with mpox viral DNA from mpox patients globally.

Methods

In this systematic review and meta-analysis, seven databases and several preprint servers have been extensively searched until 17 January 2023 according to a prospectively registered protocol (PROSPERO: CRD42023392505). Articles including the positivity rate of skin samples with mpox viral DNA in mpox-confirmed patients were considered eligible. After a quality assessment, a random-effect meta-analysis was used for pooled prevalence. To explore and resolve heterogeneity, we used statistical methods for outlier detection, influence analysis, and sensitivity analysis.

Findings

Among the 331 articles retrieved after deduplication, 14 studies were finally included. The pooled positivity rate of the skin samples was 98.77% (95% CI: 94.74%-99.72%). After the removal of an influential outlier, I ² for heterogeneity dropped from 92.5% to 10.8%. Meta-regression did not reveal any significant moderator.

Conclusion/interpretation

The present findings reinforce that skin lesions act as a reservoir of mpox viral DNA and contribute to a high infectivity risk. This may be a prevailing basis of prompt transmission during the current multicountry outbreak and also needs further investigation. The present imperative outcome may benefit in producing valuable preventive and management procedures in an appropriate health strategy.

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.

The study of human monkeypox disease in 2022 using the epidemic models: herd immunity and the basic reproduction number case

As of May 2022, a new outbreak of the human monkeypox (MPOX) disease appeared in multiple countries, where the 2022 human MPOX disease spread to more than 109 cases, excluding the suspected cases up to the end of 2022. The deaths of the 2022 human MPOX exceeded 200 cases up to the same date. The human MPOX is not a new disease, this disease was once endemic in some countries on the African continent. Despite this, this disease began to spread in a number of countries around the world in 2022. The first case of the 2022 human MPOX was recorded in the United Kingdom in May. After that date, this disease began to become a pandemic in a number of other countries, such as the United States, Spain, and Brazil. The 2022 human MPOX is a type of viral disease caused by a viral virus, the MPOX virus, and this virus causes rashes and lesions over the skin of the patient, as well as in the mouth of the patient. Multiple effective indicators are employed for the study of the 2022 of the human MPOX, such as the herd immunity of the human MPOX (HIhMPOX), the basic reproduction number of the human MPOX (BRNhMPOX), and the infection period of the human MPOX. This study focuses on the study of the herd immunity of, and the basic reproduction number of the 2022 outbreak of human MPOX in multiple countries around the world. This study employed the semianalytical method of the Susceptible compartment S, Infectious compartment I, Recovered compartment R (SIR) pandemic model including the mortality for the study of the herd immunity, and the basic reproduction number of the 2022 human MPOX disease. It is found that the average value of the herd immunity for the human MPOX disease in 2022 equals to 0.2194, that is, 21.94% for multiple countries, and equals to 35.52% for the United States, and 30.99% for Spain. Also, it is found that the average value of the basic reproduction number of the 2022 human MPOX disease equals to 1.2810 for multiple countries. It is concluded from these values that 21.94% of the total susceptible population has to be immunized in an effective way to prevent the spreading of the disease. Also, based on the previous values, it is concluded that the status of the 2022 MPOX disease is spreading as a pandemic.

Detection of Monkeypox Virus according to The Collection Site of Samples from Confirmed Cases: A Systematic Review

Due to the rapid evolution of the monkeypox virus, the means by which the monkeypox virus is spread is subject to change. Therefore, the present study aims to analyze the detection of the monkeypox virus according to the collection site of samples from confirmed monkeypox cases. A systematic literature review was performed using PubMed, Scopus, Web of Science, and Embase databases until 5 October 2022. A total of 1022 articles were retrieved using the search strategy. After removing duplicates (n = 566) and examining by title, abstract, and full text, 65 studies reporting monkeypox case reports were included with a detailed description of risk factors, sexually transmitted infections (STIs), site of monkeypox virus-positive specimens, location of skin lesions, and diagnostic test. A total of 4537 confirmed monkeypox cases have been reported, of which 98.72% of the cases were male with a mean age of 36 years, 95.72% had a sexual behavior of being men who have sex with men, and 28.1% had human immunodeficiency virus (HIV). The most frequent locations of lesions in patients diagnosed with monkeypox were: 42.85% on the genitalia and 37.1% in the perianal region. All confirmed monkeypox cases were diagnosed by reverse transcriptase polymerase chain reaction (RT-PCR), and the most frequent locations of samples collected for diagnosis that tested positive for monkeypox virus were: 91.85% from skin lesions, 20.81% from the oropharynx, 3.19% from blood, and 2.43% from seminal fluid. The disease course of the cases with monkeypox was asynchronous, with no severe complications, and most patients did not report specific treatment but simply followed a symptomatic treatment.