Molecular epidemiology of molluscum contagiosum virus and analysis of the host-serum antibody response in Spanish HIV-negative patients

A novel digital PCR assay for detection and comprehensive characterization of Molluscum contagiosum virus genotypes MOCV1, MOCV2, and MOCV3 and recombinant lineages

Molluscum contagiosum virus (MOCV) is an important human pathogen causing a high disease burden worldwide. It is the last exclusively human-infecting poxvirus still circulating in its natural reservoir-a valuable model of poxviral evolution. Unfortunately, MOCV remains neglected, and little is known about its evolutionary history and circulating genomic variants, especially in non-privileged countries. The design weaknesses of available MOCV detection/genotyping assays surfaced with recent accumulation of abundant sequence information: all existing MOCV assays fail at accurate genotyping and capturing sub-genotype level diversity. Because complete MOCV genome characterization is an expensive and labor-intensive task, it makes sense to prioritize samples for whole-genome sequencing by diversity triage screening. To meet this demand, we developed a novel assay for accurate MOCV detection and genotyping, and comprehensive sub-genotype qualification to the level of phylogenetic groups (PGs). The assay included a novel set of oligonucleotide primers and probes, and it was implemented using digital polymerase chain reaction (dPCR). It offers sensitive, specific, and accurate detection, genotyping (MOCV1-MOCV3), and PG qualification (PG1-6) of MOCV DNA from clinical samples. The novel dPCR assay is suitable for MOCV diversity triage screening and prioritization of samples for complete MOCV genome characterization.

Comprehensive analysis of 66 complete molluscum contagiosum virus (MOCV) genomes: characterization and functional annotation of 47 novel complete MOCV genomes, including the first genome of MOCV genotype 3, and a proposal for harmonized MOCV genotyping indexing

IMPORTANCE

Four molluscum contagiosum virus (MOCV) genotypes (MOCV1-4) and four subtype variants were partially characterized using restriction enzyme profiling in the 1980s/1990s, but complete genome sequences of only MOCV1 and MOCV2 are available. The evolutionary pathways whereby genotypes/subtype variants with unavailable sequences emerged and whether all MOCVs can be detected using current diagnostic approaches remain unclear. We fully characterized 47 novel complete MOCV genomes, including the first complete MOCV3 genome, expanding the number of fully characterized genomes to 66. For reliably classifying the novel non-MOCV1/2 genomes, we developed and validated a framework for matching sequence-derived restriction maps with those defining MOCV subtypes in pioneering studies. Six phylogenetic subgroups (PG1-6) were identified, PG5 representing a novel MOCV2 subtype. The phylogenetic subgroups diverged from the prototype lineages following large-scale recombination events and hinted at partial sequence content of MOCV4 and direction of recombinant transfer in the events spawning PG5 and yet undetected MOCV1vb variant.

Contributing Factors and Outcome after Cryotherapy of Molluscum Contagiosum among Patients Attending Tertiary Hospital, Northern Tanzania: A Descriptive Prospective Cohort Study

Background

Molluscum contagiosum (MC) is a benign infection caused by a member of the Poxviridae family, molluscum contagiosum virus (MCV). The contributing factors for MCV infection are different in different populations and study areas. Few studies have been conducted to determine the effectiveness of cryotherapy in the treatment of MC. The study's objectives were to determine contributing factors and outcome after cryotherapy of MC among patients attending a tertiary hospital in Northern Tanzania.

Methods

A hospital-based cohort study was conducted at the Regional Dermatology Training Centre (RDTC) from September 2018 to August 2019, involving all patients clinically diagnosed with MC. We used a consecutive sampling method to recruit study participants. We treated all participants with cryotherapy and assessed them after two weeks. Data were collected using a structured questionnaire and analyzed using Statistical Package for the Social Sciences (SPSS) software version 21.

Results

There were 49 patients with MC who agreed to participate in this study with a median age of 8 (IQR 3–22). We found 18.4% of patients with active atopic dermatitis (AD) had MC while those with a history of atopic diseases (Ad) were 32%, and 22.4% had a history of using immunosuppressive drugs. The clearance rate of cryotherapy on MC lesions was found to be 94%. Hypopigmentation was the commonest adverse effect.

Conclusion

The findings of this study show that AD and immunosuppression may be contributing to MC development. Based on the clearance rate results, cryotherapy has shown to be effective and may be used in the treatment of MC.

Molecular Screening and Single Nucleotide Polymorphism Typing of Molluscum Contagiosum Virus (MCV) from Genital Specimens, between 2012 and 2015

Background:

The present study is the first comprehensive report of the Molluscum contagiosum virus (MCV) in Iran based on the molecular technique for differentiation and typing of the MCV1 and MCV2.

Methods:

Patients were diagnosed as having tumor-like genital warts less than 5 mm in diameter, and HIV seronegative samples were chosen for this cross-sectional study. TaqMan real-time PCR was used to identify MCV following clinical examination. Typing of the MCV-positive specimens was performed in the SNP A27451G region of MC021L gene.

Results:

Of 1470 samples, 114 (7.75%) samples were positive for the MCV. From MCV-positive samples, 71.05% sequences were found to be related to the MCV1 and 28.95% to the MCV2.

Conclusion:

This assay constitutes a reliable method for identification and typing of the MCV genomic variants that could be valuable for reviewing the pathogenesis, molecular epidemiology, and the natural history of MCV-related situations.

Beetle juice: a guide for the use of cantharidin in the treatment of molluscum contagiosum

Molluscum contagiosum (MC) is an increasingly common cutaneous viral infection that primarily affects the pediatric population. MC lesions are benign, and most cases resolve within 6-9 months. Nonetheless, many patients and their parents seek active treatment of MC because of local pain, pruritus, embarrassment due to the lesions, or desire to reduce transmission to siblings. Individuals with atopic dermatitis are predisposed to severe and protracted MC, and immunocompromised patients may never clear the infection without treatment. Despite the availability of various therapies, no clear best treatment for MC has emerged. Cantharidin is a commonly used and effective therapy for MC that is generally well tolerated and has high rates of parental satisfaction. In this review, current literature regarding MC is summarized and particular focus is placed on the use of cantharidin for treating MC, including a review of the literature and detailed instructions for its use.

Recognizing and managing eczematous id reactions to molluscum contagiosum virus in children

Molluscum contagiosum (MC) is a self-limiting cutaneous viral eruption that is very common in children. MC infection can trigger an eczematous reaction around molluscum papules known as a hypersensitivity or an id reaction. In addition, a hypersensitivity reaction can occasionally occur at sites distant from the primary molluscum papules. These eczematous reactions are often asymptomatic or minimally pruritic. We believe that id reactions represent an immunologically mediated host response to MC virus and a harbinger of regression. Therefore, these reactions often do not require treatment other than emollients. Moreover, topical steroids or immunomodulators may suppress this process and potentiate the spread of the primary MC infection. However, in symptomatic patients, treatment should not be withheld and short-course treatments of topical corticosteroids may be used. In this case series, we describe 3 cases of hypersensitivity reactions in otherwise healthy children with MC. We hope that our report will make clinicians more aware of this common eczematous response to MC and will improve the management and counseling of these patients and their parents.

Estudo da correlação entre molusco contagioso e dermatite atópica em crianças

FUNDAMENTOS: É bastante divulgado, sem a fundamentação científica necessária, que a infecção por molusco contagioso tende a ser mais frequente e de maior intensidade nos pacientes acometidos por dermatite atópica. Tal fato motivou a realização deste trabalho. OBJETIVOS: Avaliar a prevalência de associação de dermatite atópica e molusco contagioso; avaliar se, nos pacientes com dermatite atópica, a infecção por molusco contagioso é mais recorrente e/ou disseminada e se a ocorrência de eczema perimolusco, prurido e/ou infecção é mais prevalente que nos pacientes sem dermatite atópica. MÉTODOS: Avaliaram-se 284 crianças de ambos os sexos, com diagnóstico de molusco contagioso e/ ou dermatite atópica. RESULTADOS: Apenas 13,4% dos pacientes apresentavam ambas as doenças. O número de áreas anatômicas afetadas por molusco contagioso, a ocorrência de eczema perimolusco e prurido foram maiores nos pacientes com dermatite atópica associada. Não houve diferença significativa de frequência de infecção secundária associada às lesões de molusco contagioso nos pacientes com e sem dermatite atópica. CONCLUSÃO: A prevalência da ocorrência de dermatite atópica e molusco contagioso associados foi baixa. Não houve diferença significativa na recorrência da infecção por molusco contagioso e na quantidade de lesões nos pacientes com e sem dermatite atópica. O número de áreas anatômicas afetadas por lesões de molusco contagioso, a presença de eczema perimolusco e de prurido foram maiores nos pacientes com dermatite atópica. Não houve diferença significativa na ocorrência de infecção bacteriana secundária nos grupos com e sem dermatite atópica

Clinical characteristics of molluscum contagiosum in children in a private dermatology practice in the greater Paris area, France: a prospective study in 661 patients

BACKGROUND

Series regarding the clinical characteristics of molluscum contagiosum (MC) are retrospective and concern small defined populations seen in a hospital setting.

METHODS

We prospectively studied patients under 15 years of age with MC seen in 25 private dermatology practices in the greater Paris area during 1 year.

RESULTS

Six hundred fifty patients were included. The mean age was 6 years. Of the patients, 30.5% had had MC in the past, 53% had 5-20 MC, 43% had a history of atopic dermatitis (AD), 5% were using topical steroids, 25.5% had coexistent AD, 13% had giant MC (>5 mm), 21% had inflammatory MC, and 19% had MC surrounded by eczema. Bathing with siblings was associated with a higher number of MC. A history of AD was associated with the presence of MC surrounded by eczema. The use of topical steroids was associated with a higher risk of relapse. There was no relation between environmental factors (MC in surrounding people, going to the swimming pool, sports practice) and the number of lesions or between environmental factors and the number of recurrences.

CONCLUSION

Atypical lesions are frequent. Bathing with siblings is associated with a higher number of MC. Topical steroid use increases the risk of relapses. AD prevalence is higher than in the general population.

Are lifetime prevalence of impetigo, molluscum and herpes infection really increased in children having atopic dermatitis?

BACKGROUND

Cutaneous infections such as impetigo contagiosum (IC), molluscum contagiosum (MC) and herpes virus infection (HI) appear to be associated with atopic dermatitis (AD), but there are no reports of concrete epidemiological evidence.

OBJECTIVE

We evaluated the association of childhood AD with these infections by conducting a population-based cross-sectional study.

METHODS

Enrolled in this study were 1117 children aged 0-6 years old attending nursery schools in Ishigaki City, Okinawa Prefecture, Japan. Physical examination was performed by dermatologists, and a questionnaire was completed on each child's history of allergic diseases including AD, asthma, allergic rhinitis and egg allergy, and that of skin infections including IC, MC and HI, as well as familial history of AD.

RESULTS

In 913 children (AD; 132), a history of IC, MC or HI was observed in 45.1%, 19.7%, and 2.5%, respectively. Multiple logistic regression analysis revealed that the odds of having a history of IC were 1.8 times higher in AD children than in non-AD children. Meanwhile, a history of MC was significantly correlated to the male gender, but not to a personal history of AD. As for HI, we found no correlated factors in this study.

CONCLUSIONS

The lifetime prevalence of IC was indeed higher in young children with a history of AD.

Curettage treatment for molluscum contagiosum: a follow-up survey study

BACKGROUND

Although curettage is commonly used to treat molluscum contagiosum, prospective studies on its effectiveness are lacking.

OBJECTIVES

To evaluate prospectively the efficacy of curettage in the treatment of molluscum contagiosum and to identify the risk factors associated with treatment failure.

METHODS

A systematic 2-month follow-up survey study was carried out on 73 patients treated by curettage for molluscum contagiosum.

RESULTS

Treatment of molluscum contagiosum by curettage was associated with a high risk of treatment failure at week 4 (42/64, 66%) and at week 8 (25/55, 45%). Risk factors for treatment failure at week 4 and 8 were the number of lesions at day 0 (P < 0.001), the number of involved anatomical sites (P < 0.001) and concomitant atopic dermatitis (P = 0.038 and P < 0.001, at weeks 4 and 8, respectively).

CONCLUSIONS

The main risk factor for treatment failure is lesion number, underlining the importance of the early detection of the lesions or, alternatively, emphasizing the need for therapeutic options other than curettage in patients with numerous lesions.

Detection of Molluscum contagiosum Virus (MCV) Subtype I as a Single Dominant Virus Subtype in Molluscum Lesions from a Turkish Population

BACKGROUND

Molluscum contagiosum has a worldwide occurrence and its primary mode of transmission is via direct human contact including sexual means. The aim of the study was to implement a polymerase chain reaction-based assay for detection and subtyping of Molluscum contagiosum virus (MCV) in skin lesions diagnosed with molluscum contagiosum in a large regional teaching hospital in Turkey.

METHODS

For this purpose, a total of 61 patients were included in the study. Randomly selected single lesion from each patient was used to extract DNA material and a specific PCR reaction amplifying 393-bp- and 575-bp-long regions from MCV genome was used in the detection. Subtyping was carried out by digestion of the amplified 575-bp product with restriction endonuclease enzyme BamHI. Both amplified and restriction enzyme digested products visualized on agarose gel electrophoresis.

RESULTS

All 61 molluscum cases (100%) included in the study contained MCV genetic material as demonstrated by the presence of 393- and 575-bp-long PCR amplified products. Restriction enzyme BamHI digestion of the 575-bp-long amplicon indicated that the infecting subtype in all the cases (100%) was MCV subtype I.

CONCLUSIONS

Results of this study demonstrate that subtype I is the only infecting strain dominant in our region. Because the only consecutive molluscum patients admitted to our hospital were included in the study, our data do not rule out the possibility that other genotypes might be present in the Turkish population. However, it is not unreasonable to conclude that similar trends exist in the rest of the country. Results also show that a molecular-based diagnostic assay would be feasible in cases where diagnosis was deemed necessary.

The epidemiology of molluscum contagiosum in children

Molluscum contagiosum (MC) is a viral disorder of the skin and mucous membranes characterized by discrete single or multiple, flesh-colored papules. Although MC as a clinical entity is well defined and commonly observed, few data regarding its epidemiology in the pediatric population exist. Our purpose was to collect epidemiologic data on children with MC with regard to age, gender, ethnicity, degree of involvement, relation to pre-existing atopic dermatitis (AD), and immune status. A retrospective chart review was conducted. All subjects were seen at 3 tertiary pediatric dermatology referral centers with two of the sites based at a Children's Hospital. A total of 302 patient charts with the Current Procedural Terminology code diagnosis of MC seen over a 6- to 8-month period were reviewed. Approximately 80% of the patients were younger than 8 years old. The majority of patients (63%) had more than 15 lesions. All but one patient were otherwise healthy, as determined by history and clinical examination. Approximately 24% of the patients presented with a history of previous or active coexistent AD. However, children with AD were at risk for an increased number of lesions. These data provide valuable updated information on the demographics and clinical presentation of MC in pediatric patients in the United States. Limitations include that this was a retrospective study with a population limited to tertiary pediatric dermatology referral centers.

Patient demographics and utilization of health care services for molluscum contagiosum

Our objective was to describe the demographics of molluscum contagiosum patients and physician utilization patterns in the United States. We obtained weighted data for office visits throughout the United States for molluscum contagiosum and common warts from the National Ambulatory Medical Care Survey (NAMCS) from 1990 to 1999. Outpatient visit data for patients diagnosed with molluscum contagiosum were analyzed using statistical software and compared to those for patients diagnosed with common warts. The main outcome measures studied were physician office visits by patients with molluscum contagiosum and patient demographic parameters including age, gender, and race. We found that health care utilization for molluscum contagiosum was the greatest for patients <or=9 years of age (51%). Ninety-three percent of patients diagnosed with molluscum contagiosum were white. The number of visits for molluscum contagiosum was evenly divided between males and females. Visits to dermatologists comprised the majority of health care utilization units for molluscum contagiosum (71%). In conclusion, visits for molluscum contagiosum are frequent and are most often handled by dermatologists. When compared to those for common warts, molluscum contagiosum visits are less common and have an age distribution more limited to children.

Smallpox: the basics

Variola major is the causative agent of smallpox, a severe disease that was arguably one of the most serious human pathogens in recorded history. Humans are the only known reservoir of variola major; no known animal or insect reservoirs have been identified. Thus, after eradication of smallpox through a global immunization effort, this incredibly lethal scourge was eliminated from all corners of the globe. Despite the total eradication of naturally occurring smallpox, there are still stockpiles of smallpox virus maintained in the United States and the former Soviet Union. Unfortunately, it is impossible to know if all smallpox stocks have been accounted for or whether unknown or unreported stocks of smallpox may still exist. In the age of genetic engineering, these viruses could theoretically be modified to increase their virulence to the levels associated with smallpox itself.