Eczema vaccinatum

Interferon lambda restricts herpes simplex virus skin disease by suppressing neutrophil-mediated pathology

Type III interferons (IFN-λ) are antiviral and immunomodulatory cytokines that have been best characterized in respiratory and gastrointestinal infections, but the effects of IFN-λ against skin infections have not been extensively investigated. We sought to define the skin-specific effects of IFN-λ against the highly prevalent human pathogen, herpes simplex virus (HSV). We infected mice lacking the IFN-λ receptor (Ifnlr1-/-), both the IFN-λ and the IFN-α/β receptors (Ifnar1-/-Ifnlr1-/-), or IFN-λ cytokines (Ifnl2/3-/-) and found that IFN-λ restricts the severity of HSV-1 and HSV-2 skin lesions without affecting viral loads. We used RNAseq to define IFN-λ- and IFN-β-induced transcriptional responses in primary mouse keratinocytes. Using conditional knockout mice, we found that IFN-λ signaling in both keratinocytes and neutrophils was necessary to control HSV-1 skin lesion severity and that IFN-λ signaling in keratinocytes suppressed CXCL9-mediated neutrophil recruitment to the skin. Furthermore, depleting neutrophils or blocking CXCL9 protected against severe HSV-1 skin lesions in Ifnlr1-/- mice. Altogether, our results suggest that IFN-λ plays an immunomodulatory role in the skin that restricts neutrophil-mediated pathology during HSV infection and suggests potential applications for IFN-λ in treating viral skin infections.IMPORTANCEType III interferons (IFN-λ) have been shown to have antiviral and immunomodulatory effects at epithelial barriers such as the respiratory and gastrointestinal tracts, but their effects on the skin have not been extensively investigated. We used mice lacking IFN-λ signaling to investigate the skin-specific effects of IFN-λ against the herpes simplex virus (HSV), which targets epithelial tissues to cause cold sores and genital herpes. We found that IFN-λ limited the severity of HSV skin lesions without affecting viral load and that this protective effect required IFN-λ signaling in both keratinocytes and neutrophils. We found that IFN-λ signaling in keratinocytes suppressed neutrophil recruitment to the skin and that depleting neutrophils protected against severe HSV skin lesions in the absence of IFN-λ. Altogether, our results suggest that IFN-λ plays an immunomodulatory role in the skin that restricts neutrophil-mediated pathology during HSV infection and suggests potential applications for IFN-λ in treating viral skin infections.

Interferon lambda restricts herpes simplex virus skin disease by suppressing neutrophil-mediated pathology

Type III interferons (IFN-λ) are antiviral and immunomodulatory cytokines that have been best characterized in respiratory and gastrointestinal infections, but the effects of IFN-λ against skin infections have not been extensively investigated. We sought to define the skin-specific effects of IFN-λ against the highly prevalent human pathogen herpes simplex virus (HSV). We infected mice lacking the IFN-λ receptor (Ifnlr1-/-), both the IFN-λ and the IFN-αβ receptor (Ifnar1-/- Ifnlr1-/-), or IFN-λ cytokines (Ifnl2/3-/-) and found that IFN-λ restricts the severity of HSV-1 and HSV-2 skin lesions, independent of a direct effect on viral load. Using conditional knockout mice, we found that IFN-λ signaling in both keratinocytes and neutrophils was necessary to control HSV-1 skin lesion severity, and that IFN-λ signaling in keratinocytes suppressed CXCL9-mediated neutrophil recruitment to the skin. Furthermore, depleting neutrophils or blocking CXCL9 protected against severe HSV-1 skin lesions in Ifnlr1-/- mice. Altogether, our results suggest that IFN-λ plays an immunomodulatory role in the skin that restricts neutrophil-mediated pathology during HSV infection, and suggest potential applications for IFN-λ in treating viral skin infections.

Recent Advances in Research and Management of Human Monkeypox Virus: An Emerging Global Health Threat

In 2003, the United States saw an epidemic of monkeypox that was later traced back to rodents of West Africa infected with the monkeypox virus (MPXV). Disease in the United States seemed less severe than the smallpox-like disease in the Democratic Republic of the Congo (DRC). In this study, researchers analyzed data from Central Africa: two distinct MPXV clades were confirmed by sequencing the genomes of MPXV isolates from Western Africa, the United States, and Central Africa. By comparing open reading frames across MPXV clades, scientists can infer which virus proteins might account for the observed variation in pathogenicity in humans. Monkeypox can be prevented and controlled with a better understanding of MPXV's molecular etiology and epidemiological and clinical features. In light of the current outbreaks worldwide, we provide updated information on monkeypox for medical professionals in this review.

A Rare Case of Delayed Hypersensitivity Following COVID-19 Booster Necessitating Treatment With Dupilumab

Following vaccination, patients can develop symptoms of eczema flare, which could range from mild skin irritation and urticaria to diffuse skin involvement. Delayed immunologic reactions have been described in association with the novel mRNA COVID-19 vaccines and boosters. We report the case of an 83-year-old female who presented with widespread pruritic urticarial indurated papules on the arms, legs, and palms, sparing the face six months following the booster vaccine. She denied constitutional symptoms, new medications, recent illnesses, or new personal care products. Punch biopsy demonstrated acanthosis, spongiosis, and superficial and mild dermal perivascular lymphocytic infiltration with occasional eosinophils compatible with a dermal hypersensitivity reaction. The patient was admitted to the hospital due to the need for systemic steroids as well as IV antibiotics secondary to a superimposed bacterial skin infection in the setting of severe itching and skin injury; she was discharged on oral steroids with follow-up to dermatology and rheumatology. Delayed hypersensitivity reactions typically peak within four days following vaccination and may be observed with COVID-19 vaccines or boosters. However, reports remain limited, and people's history of eczema should not preclude them from receiving a COVID-19 vaccine that is both safe and effective.

Mpox (monkeypox): Diagnosis, prevention, and management in adults

ABSTRACT

Mpox (formerly "monkeypox") is a viral zoonosis that presents similarly to smallpox but is less contagious and causes less severe disease. Mpox may be transmitted from infected animals to humans through direct contact or a scratch or bite. Human-to-human transmission occurs through direct contact, respiratory droplets, and fomites. Two vaccines, JYNNEOS® and ACAM2000®, are currently available for postexposure prophylaxis as well as for prevention in certain populations at high risk for mpox. Most cases of mpox are self-limited; however, tecovirimat, brincidofovir, and cidofovir are available as treatments for at-risk populations.

Interim Clinical Treatment Considerations for Severe Manifestations of Mpox - United States, February 2023

Monkeypox (mpox) is a disease caused by infection with Monkeypox virus (MPXV), an Orthopoxvirus (OPXV) in the same genus as Variola virus, which causes smallpox. During 2022, a global outbreak involving mpox clade IIb was recognized, primarily among gay, bisexual, and other men who have sex with men.* Most affected patients have been immunocompetent and experienced ≤10 rash lesions (1). CDC has recommended supportive care including pain control.^† However, some patients have experienced severe mpox manifestations, including ocular lesions, neurologic complications, myopericarditis, complications associated with mucosal (oral, rectal, genital, and urethral) lesions, and uncontrolled viral spread due to moderate or severe immunocompromise, particularly advanced HIV infection (2). Therapeutic medical countermeasures (MCMs) are Food and Drug Administration (FDA)-regulated drugs and biologics that are predominantly stockpiled by the U.S. government; MCMs developed for smallpox preparedness or shown to be effective against other OPXVs (i.e., tecovirimat, brincidofovir, cidofovir, trifluridine ophthalmic solution, and vaccinia immune globulin intravenous [VIGIV]) have been used to treat severe mpox. During May 2022-January 2023, CDC provided more than 250 U.S. mpox consultations. This report synthesizes data from animal models, MCM use for human cases of related OPXV, unpublished data, input from clinician experts, and experience during consultations (including follow-up) to provide interim clinical treatment considerations. Randomized controlled trials and other carefully controlled research studies are needed to evaluate the effectiveness of MCMs for treating human mpox. Until data gaps are filled, the information presented in this report represents the best available information concerning the effective use of MCMs and should be used to guide decisions about MCM use for mpox patients.

Monkeypox outbreak, vaccination, and treatment implications for the dermatologic patient: Review and interim guidance from the Medical Dermatology Society

Rapid human-to-human transmission of monkeypox has created a public health emergency requiring prompt, multidisciplinary attention. Dermatologists are at the forefront of diagnosis due to the disease-defining skin lesions. Moreover, patients with pre-existing skin disease and those who are on immunosuppressive medications for skin disease may be at increased risk of severe infection. In this review, a panel of authors with expertise in complex medical dermatology and managing patients on immunosuppression reviews the literature and provides initial guidance for diagnosis and management in dermatology practices. Though there are knowledge gaps due to a lack of controlled studies, we support use of replication-deficit vaccines in all dermatologic patients who meet qualifying risk or exposure criteria. We offer strategies to optimize vaccine efficacy in patients with immunosuppression. We discuss alternative post-exposure treatments and their safety profiles. Finally, we outline supportive care recommendations for cutaneous manifestations of monkeypox. Large scale epidemiologic investigations and clinical trials will ultimately revise and extend our guidance.

Effect of COVID-19 (SARS-CoV-2) Vaccination on Patients with Atopic Dermatitis Treated with Dupilumab: A Multicenter, Observational Study

BACKGROUND

Atopic dermatitis (AD) patients usually wonder if their condition will worsen after vaccination or if they should continue with the treatment they are receiving. Considering that many patients treated with dupilumab had previously experienced severe AD symptoms and flares, the concerns are more understandable.

OBJECTIVE

This study aimed to investigate the safety of the coronavirus disease 2019 (COVID-19) vaccination in patients with AD treated with dupilumab.

METHODS

We enrolled 133 patients (101 dupilumab-treated and 32 systemic oral agents-treated as control group) with AD from six hospitals. Patients were asked about worsening pruritus and AD (5-point Likert scale) after vaccination. AD variables (eczema area and severity index [EASI], investigator's global assessment [IGA], itch numerical rating scale [NRS], sleep NRS, and patient-oriented eczema measure [POEM]) were compared pre- and post-vaccination. Adverse reactions to the COVID-19 vaccination were observed.

RESULTS

The incidence of adverse reactions to COVID-19 vaccines and worsening AD symptoms in dupilumab-treated patients were not significantly different compared with that in the control group. The itch NRS score increased significantly after vaccination (p<0.001). However, there were no statistically significant differences between the pre-and post-EASI, IGA, and POEM scores. Eight patients (7.9%) had worse EASI scores and required rescue therapy; however, most were easily managed with low-dose steroids or topical agents. None of the patients discontinued dupilumab treatment.

CONCLUSION

No serious adverse reactions were observed in patients with AD after COVID-19 vaccination. Exacerbation of pruritus and AD symptoms was observed but was mostly mild and transient.

Primary Mpox and Secondary Syphilis in an HIV Patient: A Community Hospital Experience

Mpox was an emerging outbreak in California in 2022, primarily in major metropolitan areas, as part of the global mpox outbreak declared by World Health Organization in July 2022. Community hospitals outside of major metropolitan areas have seen fewer cases to date, so they may be less equipped to diagnose and treat patients with mpox. They may have limited public health resources commensurate with the area's population density. Mpox may also be superimposed on ongoing local outbreaks of other sexually transmitted infections. We present a case of a person with HIV who contracted mpox and also developed secondary syphilis. Early detection can be beneficial for prompt treatment, decreased burden of disease for the individual, and prevention of further spread of the infection.

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.

Genetic/Environmental Contributions and Immune Dysregulation in Children with Atopic Dermatitis

Atopic dermatitis (AD) is one of the most common skin conditions in humans. AD affects up to 20% of children worldwide and results in morbidity for both patients and their caregivers. The basis of AD is an interplay between genetics and the environment characterized by immune dysregulation. A myriad of mutations that compromise the skin barrier and/or immune function have been linked to AD. Of these, filaggrin gene (FLG) mutations are the most evidenced. Many other mutations have been implicated in isolated studies that are often unreplicated, creating an archive of genes with potential but unconfirmed relevance to AD. Harnessing big data, polygenic risk scores (PRSs) and genome-wide association studies (GWAS) may provide a more practical strategy for identifying the genetic signatures of AD. Epigenetics may also play a role. Staphylococcus aureus is the most evidenced microbial contributor to AD. Cutaneous dysbiosis may result in over-colonization by pathogenic strains and aberrant skin immunity and inflammation. Aeroallergens, air pollution, and climate are other key environmental contributors to AD. The right climate and/or commensals may improve AD for some patients.

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.

Knowledge and vaccination acceptance toward the human monkeypox among men who have sex with men in China

Background

MSM individuals are at high risk of monkeypox infection, and judicious use of vaccines can control the outbreak. Therefore, we conducted a national cross-sectional survey to assess the vaccination willingness, associated factors, and related knowledges of monkeypox among MSM individuals in China.

Methods

This anonymous cross-sectional study was conducted in China from July 1 to July 3, 2022, and electronic questionnaires were sent online to MSM individuals of specific institutions. Men, aged 18 or older, who had anal sex in the past year were recruited. Multivariable logistic regression models and univariable logistic regression models were performed in different groups of participants, including all eligible respondents, people with or without self-reported HIV infection, and people who had sex with at least one male sexual partner in last month.

Results

A total of 2,618 male respondents, including 2,134 homosexuals and 484 bisexuals, were enrolled in our final analysis. Most of the respondents had a certain understanding of the source of infection, transmission route, and preventive measures, but lacked knowledge of the susceptible population, clinical manifestations, vaccination, and treatment. In total, 90.2% of all respondents were willing to receive the vaccines against monkeypox. Among people with self-reported HIV infection, the vaccination acceptance rate was 91.7%, while it was 89.7% in the rest. The main influencing factors were knowledge about monkeypox (moderate: aOR = 1.47, 95% CI: 1.04-2.08; high: aOR = 2.03, 95% CI: 1.23-3.34), knowledge about prevention measures (moderate: aOR = 3.52, 95% CI: 2.51-4.94; high: aOR = 5.32, 95% CI: 2.98-9.47), concerns about their susceptibility to monkeypox infection (aOR = 4.37, 95% CI: 3.29-5.80), and possible contact with people and animals in epidemic areas (aOR = 0.42, 95% CI: 0.25-0.70). For self-reported HIV-infected individuals, education (bachelor degree: aOR = 0.40, 95% CI: 0.18-0.89) and poor condom use (sometimes: aOR = 2.18, 95% CI: 1.06-4.47) may also affect the vaccination.

Conclusions

There was still a lack of knowledge about the human monkeypox among MSM individuals in China. The vaccination acceptance rate of this high-risk population was high, and it was closely related to the knowledge factors, fear of infection, and possible contact with people or animals in affected areas. Targeted publicity and education of the high-risk groups, vaccination pre-arranged planning should be formulated to cope with the further development of this infectious disease.

Repositioning potentials of smallpox vaccines and antiviral agents in monkeypox outbreak: A rapid review on comparative benefits and risks

Background and aims

There is a sought for vaccines and antiviral agents as countermeasures for the recent monkeypox outbreak. Here, we aimed to review and discuss the repurposing potentials of smallpox vaccines and drugs in monkeypox outbreaks based on their comparative benefits and risks. Therefore, we conducted this rapid review and discussed the repurposing potentials of smallpox vaccines and drugs in monkeypox infection.

Methods

Here, we searched Google Scholar and PubMed for relevant information and data. We found many articles that have suggested the use of smallpox vaccines and antiviral drugs in monkeypox outbreaks according to the study findings. We read the relevant articles to extract information.

Results

According to the available documents, we found two replication‐competent and one replication‐deficient vaccinia vaccines were effective against Orthopoxvirus. However, the healthcare authorities have authorized second‐generation live vaccina virus vaccines against Orthopoxvirus in many countries. Smallpox vaccine is almost 85% effective in preventing monkeypox infection as monkeypox virus, variola virus, and vaccinia virus are similar. The United States and Canada have approved a replication‐deficient third‐generation smallpox vaccine for the prevention of monkeypox infection. However, the widely used second‐generation smallpox vaccines contain a live virus and replicate it into the human cell. Therefore, there is a chance to cause virus‐induced complications among the vaccinated subjects. In those circumstances, the available Orthopoxvirus inhibitors might be a good choice for treating monkeypox infections as they showed similar efficacy in monkeypox infection in different animal model clinical trials. Also, the combined use of antiviral drugs and vaccinia immune globulin can enhance significant effectiveness in immunocompromised subjects.

Conclusion

Repurposing of these smallpox vaccines and antiviral agents might be weapons to fight monkeypox infection. Also, we recommend further investigations of smallpox vaccines and Orthopoxvirus inhibitors in a human model study to explore their exact role in human monkeypox infections.

Monkeypox: A clinical update for paediatricians

The global spread of human monkeypox disease, a zoonotic infection related to smallpox and endemic to West and Central Africa, presents serious challenges for health systems. As of July 2022, 14 533 cases have been reported world-wide, leading to designation as a Public Health Emergency of International Concern. Monkeypox disease is spread from animals to humans through infected lesions or fluids; human-human transmission occurs through fomites, droplets or direct contact. Illness is usually self-limiting, but severe disease can occur in specific groups - particularly children, and people who are immunocompromised or pregnant. Clinical presentation may include fever, lymphadenopathy and skin rash, but the rash may occur without other symptoms. Complications can include secondary bacterial infection of skin lesions, vision loss from corneal involvement, pneumonia, sepsis and encephalitis. Diagnosis of monkeypox requires consideration of epidemiological, clinical and laboratory findings, with sensitive history-taking, to elicit close contacts, critical. Supportive management is usually sufficient, but treatment options (where required) include antivirals and vaccinia immune globulin. A paucity of safety data for relevant antivirals may limit their use. There are two types of monkeypox vaccines: a replication-competent vaccinia vaccine, the use of which is logistically and clinically complex, and a replication-deficient modified vaccinia Ankara virus vaccine. Preparedness of health systems for addressing the current outbreak is constrained by historic underfunding for research, and compounded by stigma and discrimination against cases and affected communities. Key challenges in halting transmission include improving vaccine equity and countering discrimination against men who have sex with men to aid diagnosis and treatment.

Signaling sphingolipids are biomarkers for atopic dermatitis prone to disseminated viral infections

BACKGROUND

Life-threatening viral diseases such as eczema herpeticum (EH) and eczema vaccinatum (EV) occur in <5% of individuals with atopic dermatitis (AD). The diagnosis of AD, however, excludes all individuals with AD from smallpox vaccination.

OBJECTIVES

We sought to identify circulatory and skin lipid biomarkers associated with EH and EV.

METHODS

Stratum corneum and plasma samples from 15 subjects with AD and a history of EH, 13 age- and gender-matched subjects with AD and without EH history, and 13 healthy nonatopic (NA) controls were analyzed by liquid chromatography tandem mass spectrometry for sphingolipid content. Sphingosine-1-phosphate (S1P) and ceramide levels were validated in plasma samples from the Atopic Dermatitis Vaccinia Network/Atopic Dermatitis Research Network repository (12 NA, 12 AD, 23 EH) and plasma from 7 subjects with EV and 7 matched subjects with AD. S1P lyase was downregulated in human primary keratinocytes to evaluate its effect on herpes simplex virus 1 (HSV-1) replication in vitro.

RESULTS

The stratum corneum of patients with EH demonstrated significantly higher levels of free sphingoid bases than those in patients who were NA, indicating enhanced sphingolipid turnover in keratinocytes (P < .05). Plasma from 2 independent cohorts of patients with EH had a significantly increased S1P/ceramide ratio in subjects with EH versus those with AD and or who were NA (P < .01). The S1P level in plasma from subjects with EV was twice the level in plasma from subjects with AD (mean = 1,533 vs 732 pmol/mL; P < .001). Downregulation of S1P lyase expression with silencing RNA led to an increased S1P level and doubled HSV-1 titer in keratinocytes.

CONCLUSIONS

Our data point to long-term abnormalities in the S1P signaling system as a biomarker for previous disseminated viral diseases and a potential treatment target in recurring infections.

Monkeypox - A Contemporary Review for Healthcare Professionals

The ongoing 2022 multicountry outbreak of monkeypox is the largest in history to occur outside of Africa. Monkeypox is an emerging zoonotic disease that for decades has been viewed as an infectious disease with significant epidemic potential because of the increasing occurrence of human outbreaks in recent years. As public health entities work to contain the current outbreak, healthcare professionals globally are aiming to become familiar with the various clinical presentations and management of this infection. We present in this review an updated overview of monkeypox for healthcare professionals in the context of the ongoing outbreaks around the world.

Atopic dermatitis: pathomechanisms and lessons learned from novel systemic therapeutic options

Atopic dermatitis (AD) is a chronic, heterogenous, inflammatory skin disorder associated with a high skin-related health burden, typically starting in childhood and often persisting into adulthood. AD is characterized by a wide range of clinical phenotypes, reflecting multiple underlying pathophysiological mechanisms and interactions between genetics, immune system dysregulation, and environmental factors. In this review, we describe the diverse cellular and molecular mechanisms involved in AD, including the critical role of T cell-driven inflammation, primarily via T helper (Th) 2- and Th17-derived cytokines, many of which are mediated by the Janus kinase (JAK) signaling pathway. These local inflammatory processes interact with sensory neuronal pathways, contributing to the clinical manifestations of AD, including itch, pain, and sleep disturbance. The recent elucidation of the molecular pathways involved in AD has allowed treatment strategies to evolve from broad-acting systemic immunosuppressive therapies to more targeted agents, including JAK inhibitors and cytokine-specific biologic agents. Evidence from the clinical development of these targeted therapies has reinforced and expanded our understanding of the pathophysiological mechanisms underlying AD and holds promise for individualized treatment strategies tailored to specific AD subtypes.

Conditions That Simulate the Environment of Atopic Dermatitis Enhance Susceptibility of Human Keratinocytes to Vaccinia Virus

Individuals with underlying chronic skin conditions, notably atopic dermatitis (AD), are disproportionately affected by infections from members of the herpesviridae, papovaviridae, and poxviridae families. Many patients with AD experience recurrent, widespread cutaneous viral infections that can lead to viremia, serious organ complications, and even death. Little is known about how the type 2 inflammatory environment observed in the skin of AD patients impacts the susceptibility of epidermal cells (keratinocytes) to viral pathogens. Herein, we studied the susceptibility of keratinocytes to the prototypical poxvirus, vaccinia virus (VV)-the causative agent of eczema vaccinatum-under conditions that simulate the epidermal environment observed in AD. Treatment of keratinocytes with type 2 cytokines (IL-4 and -13) to simulate the inflammatory environment or a tight junction disrupting peptide to mirror the barrier disruption observed in AD patients, resulted in a differentiation-dependent increase in susceptibility to VV. Furthermore, pan JAK inhibition was able to diminish the VV susceptibility occurring in keratinocytes exposed to type 2 cytokines. We propose that in AD, the increased viral susceptibility of keratinocytes leads to enhanced virus production in the skin, which contributes to the rampant dissemination and pathology seen within patients.

Severe monkeypox with superimposed bacterial infection in an immunocompetent patient: A case report

Monkeypox, a member of the Orthopoxvirus genu, has been the center of global attention since it has been declared a public health emergency by the World Health Organization. Typically, it is a self-limiting disease; however, it can occasionally have severe presentations in patients with underlying conditions, such as HIV, malignancy, and transplantation. In this article, we will present a case of an immunocompetent patient with a severe presentation of monkeypox. The patient presented with facial pustules with superimposed bacterial infection; furthermore, he had painful vesicles in oral and nasal mucosa and the penis. Dermatologic conditions such as atopic dermatitis has been associated with severe monkeypox. While our patient does not have a history of atopic dermatitis, he does report contact dermatitis as well as a history of skin infections. Researchers have hypothesized that disruption of the skin barrier allows for proliferation of the monkeypox virus; therefore, it is important to take a thorough history of the patient’s skin conditions. Lastly, we described the use of Tecovirimat in our patient. Although it is impossible to demonstrate the efficacy of this medication without a randomized clinical trial, our patient seemed to have a faster improvement of the lesions after initiating this antiviral.

Vaccinia Virus Expressing Interferon Regulatory Factor 3 Induces Higher Protective Immune Responses against Lethal Poxvirus Challenge in Atopic Organism

Vaccinia virus (VACV) is an enveloped DNA virus from the Orthopoxvirus family, various strains of which were used in the successful eradication campaign against smallpox. Both original and newer VACV-based replicating vaccines reveal a risk of serious complications in atopic individuals. VACV encodes various factors interfering with host immune responses at multiple levels. In atopic skin, the production of type I interferon is compromised, while VACV specifically inhibits the phosphorylation of the Interferon Regulatory Factor 3 (IRF-3) and expression of interferons. To overcome this block, we generated a recombinant VACV-expressing murine IRF-3 (WR-IRF3) and characterized its effects on virus growth, cytokine expression and apoptosis in tissue cultures and in spontaneously atopic Nc/Nga and control Balb/c mice. Further, we explored the induction of protective immune responses against a lethal dose of wild-type WR, the surrogate of smallpox. We demonstrate that the overexpression of IRF-3 by WR-IRF3 increases the expression of type I interferon, modulates the expression of several cytokines and induces superior protective immune responses against a lethal poxvirus challenge in both Nc/Nga and Balb/c mice. Additionally, the results may be informative for design of other virus-based vaccines or for therapy of different viral infections.

Recommendations for dermatologists treating patients with atopic dermatitis during the Covid-19 pandemic: a look into the past for a conscious vaccination management

Atopic dermatitis (AD) is a chronic inflammatory skin disease that affects approximately 20% of children and 10% of adults. The implication of vaccines as a trigger for the de novo onset of AD in children or as a cause of exacerbation in individuals with a history of AD has long been debated. We present a brief review of the literature on AD and traditional vaccinations, proposing in addition the main recommendations for the management of patients with AD undergoing the vaccine against the SARS-COV-2 virus. Live attenuated vaccines seem to be associated with a relapse of AD and/or complications, such as eczema vaccinatum. For non-live vaccines, no adverse events are noted in atopic subjects. Since the Covid-19 vaccine is mRNA or viral vectored vaccine and there are no other currently used vaccines of this type, the same recommendations are applied as for all other non-live vaccines.

Safety and Efficacy of Vaccines during COVID-19 Pandemic in Patients Treated with Biological Drugs in a Dermatological Setting

The BNT162b2 and mRNA-1273 vaccines, consisting of mRNA, have recently become available. The absolute novelty of these vaccines introduces questions about their safety and efficacy, especially in patients who are treated with biological drugs in dermatology. The aim of our review was to provide a broad overview of the current use of all available vaccinations in concomitance with biological therapy and to suggest indications for the new mRNA Covid-19 vaccines. We conducted a narrative review of the literature regarding the indications and safety of the various types of vaccines currently available in dermatological patients treated with biological therapy. The safety and efficacy of administering inactivated vaccines in patients undergoing biological therapy with inhibitors of TNF-α, IL-17, IL-12/23, and IL-4/13 was confirmed. Inactivated vaccines can be administered during therapy with inhibitors of IL-23 and IgE, taking into account that the level of evidence is lower due to the lack of specific studies. Live attenuated vaccines were contraindicated in concomitance with all biological therapies considered, except omalizumab. According to this evidence, we assume that there are currently no contraindications to the administration of the new Covid-19 BNT162b2 and mRNA-1273 vaccines during biological therapy with inhibitors of TNF-α, IL-17, IL-12/23, IL-23, and IL-4/13, since these vaccines are comparable to inactivated ones. For patients with chronic urticaria or allergic asthma treated with omalizumab, we currently recommend caution in using the mRNA Covid-19 vaccines (30 min observation). The only contraindications were a previous history of hypersensitivity to the Covid-19 vaccines themself or to their excipients. In conclusion, further randomized clinical trials are needed to evaluate the efficacy of the antibody response in these patients.

Exogenous factors in the pathogenesis of atopic dermatitis: Irritants and cutaneous infections

Atopic dermatitis (AD) is a chronic relapsing inflammatory cutaneous disease that is often associated with other atopic symptoms, such as food allergy, allergic rhinitis and asthma, leading to significant morbidity and healthcare costs. The pathogenesis of AD is complicated and multifactorial. Although the aetiology of AD remains incompletely understood, recent studies have provided further insight into AD pathophysiology, demonstrating that the interaction among genetic predisposition, immune dysfunction and environmental provocation factors contributes to its development. However, the increasing prevalence of AD suggests that environmental factors such as irritation and cutaneous infection play a crucial role in triggering and/or aggravating the disease. Of note, AD skin is susceptible to bacterial, fungal and viral infections, and microorganisms may colonize the skin and aggravate AD symptoms. Overall, understanding the mechanisms by which these risk factors affect the cutaneous immunity of patients with AD is of great importance for developing a precision medicine approach for treatment. This review summarizes recent developments in exogenous factors involved in the pathogenesis of AD, with special emphasis on irritants and microbial infections.

Contact Transmission of Vaccinia to an Infant Diagnosed by Viral Culture and Metagenomic Sequencing

Targeted molecular diagnostic tests and accurate immunoassays have transformed the landscape of clinical virology, calling into question the usefulness of traditional viral culture. Here we present a case where viral culture, followed by metagenomic sequencing, was central to the diagnosis of an unexpected viral infection, with significant clinical and public health implications.

Infections in Dupilumab Clinical Trials in Atopic Dermatitis: A Comprehensive Pooled Analysis

BACKGROUND

Patients with moderate-to-severe atopic dermatitis (AD) have increased infection risk, including skin infections and systemic infections. Immunomodulators (e.g., anti-tumor necrosis factors, anti-interleukin [anti-IL]-23, anti-IL-17, Janus kinase inhibitors) increase risk of infections. Dupilumab (a monoclonal antibody blocking the shared receptor component for IL-4 and IL-13) is approved for inadequately controlled moderate-to-severe AD and for moderate-to-severe eosinophilic or oral corticosteroid-dependent asthma.

OBJECTIVE

The aim was to determine the impact of dupilumab on infection rates in patients with moderate-to-severe AD.

METHODS

This analysis pooled data from seven randomized, placebo-controlled dupilumab trials in adults with moderate-to-severe AD. Exposure-adjusted analyses assessed infection rates.

RESULTS

Of 2932 patients, 1091 received placebo, 1095 dupilumab 300 mg weekly, and 746 dupilumab 300 mg every 2 weeks. Treatment groups had similar infection rates overall per 100 patient-years (placebo, 155; dupilumab weekly, 150; dupilumab every 2 weeks, 156; dupilumab combined, 152), and similar non-skin infection rates. Serious/severe infections were reduced with dupilumab (risk ratio 0.43; p < 0.05), as were bacterial and other non-herpetic skin infections (risk ratio 0.44; p < 0.001). Although herpesviral infection rates overall were slightly higher with dupilumab than placebo, clinically important herpesviral infections (eczema herpeticum, herpes zoster) were less common with dupilumab (risk ratio 0.31; p < 0.01). Systemic anti-infective medication use was lower with dupilumab.

CONCLUSIONS

Dupilumab is associated with reduced risk of serious/severe infections and non-herpetic skin infections and does not increase overall infection rates versus placebo in patients with moderate-to-severe AD. CLINICALTRIALS.

GOV IDENTIFIERS

NCT01548404, NCT02210780, NCT01859988, NCT02277743, NCT02277769, NCT02260986, and NCT02755649.

Vaccinating against monkeypox in the Democratic Republic of the Congo

Healthcare-associated transmission of monkeypox has been observed on multiple occasions in areas where the disease is endemic. Data collected by the US Centers for Disease Control and Prevention (CDC) from an ongoing CDC-supported program of enhanced surveillance in the Tshuapa Province of the Democratic Republic of the Congo, where the annual incidence of human monkeypox is estimated to be 3.5-5/10,000, suggests that there is approximately one healthcare worker infection for every 100 confirmed monkeypox cases. Herein, we describe a study that commenced in February 2017, the intent of which is to evaluate the effectiveness, immunogenicity, and safety of a third-generation smallpox vaccine, IMVAMUNE®, in healthcare personnel at risk of monkeypox virus (MPXV) infection. We describe procedures for documenting exposures to monkeypox virus infection in study participants, and outline lessons learned that may be of relevance for studies of other investigational medical countermeasures in hard to reach, under-resourced populations.

Consensus-based European guidelines for treatment of atopic eczema (atopic dermatitis) in adults and children: part II

This guideline was developed as a joint interdisciplinary European project, including physicians from all relevant disciplines as well as patients. It is a consensus-based guideline, taking available evidence from other guidelines, systematic reviews and published studies into account. This second part of the guideline covers antimicrobial therapy, systemic treatment, allergen-specific immunotherapy, complementary medicine, psychosomatic counselling and educational interventions, whereas the first part covers methods, patient perspective, general measures and avoidance strategies, basic emollient treatment and bathing, dietary intervention, topical anti-inflammatory therapy, phototherapy and antipruritic therapy. Management of AE must consider the individual clinical variability of the disease. Systemic immunosuppressive treatment with cyclosporine, methotrexate, azathioprine and mycophenolic acid is established option for severe refractory cases, and widely available. Biologicals targeting the T helper 2 pathway such as dupilumab may be a safe and effective, disease-modifying alternative when available. Oral drugs such as JAK inhibitors and histamine 4 receptor antagonists are in development. Microbial colonization and superinfection may cause disease exacerbation and can require additional antimicrobial treatment. Allergen-specific immunotherapy with aeroallergens may be considered in selected cases. Psychosomatic counselling is recommended especially in stress-induced exacerbations. Therapeutic patient education ('Eczema school') is recommended for children and adult patients. General measures, basic emollient treatment, bathing, dietary intervention, topical anti-inflammatory therapy, phototherapy and antipruritic therapy have been addressed in the first part of the guideline.

Infectious Complications in Atopic Dermatitis

Atopic dermatitis is characterized by the interplay of skin barrier defects with the immune system and skin microbiome that causes patients to be at risk for infectious complications. This article reviews the pathogenesis of atopic dermatitis and the mechanisms through which patients are at risk for infection from bacterial, viral, and fungal pathogens. Although these complications may be managed acutely, prevention of secondary infections depends on a multipronged approach in the maintenance of skin integrity, control of flares, and microbial pathogens.

Effects of Allergic Sensitization on Antiviral Immunity: Allergen, Virus, and Host Cell Mechanisms

PURPOSE OF REVIEW

Multiple clinical and epidemiological studies demonstrate links between allergic sensitization and virus-induced atopic disease exacerbations. This review summarizes the recent findings regarding allergen, viral, and host cellular mechanisms relevant to these observations.

RECENT FINDINGS

Recent studies have focused on the molecular pathways and genetic influences involved in allergen-mediated inhibition of innate antiviral immune responses. Multiple tissue and cell types from atopic individuals across the atopy spectrum exhibit deficient interferon responses to a variety of virus infections. Impairment in barrier function, viral RNA and DNA recognition by intracellular sensing molecules, and dysregulation of signaling components are broadly affected by allergic sensitization. Finally, genetic predisposition by numerous nucleotide polymorphisms also impacts immune pathways and potentially contributes to virus-associated atopic disease pathogenesis. Allergen-virus interactions in the setting of atopy involve complex tissue and cellular mechanisms. Future studies defining the pathways underlying these interactions could uncover potential therapeutic targets. Available data suggest that therapies tailored to restore specific components of antiviral responses will likely lead to improved clinical outcomes in allergic disease.

Induction, treatment and prevention of eczema vaccinatum in atopic dermatitis mouse models

Eczema vaccinatum is a severe and occasionally lethal complication of smallpox vaccine, characterized by systemic viral dissemination, distant from the initial inoculation site of the vaccine. A major risk factor for eczema vaccinatum is a background of atopic dermatitis, a chronic, common allergic, relapsing disorder, manifested by dry and inflamed skin, itchy rash, Th2 biased immune response and hypersensitivity to various antigens. Unlike the severe manifestations of eczema vaccinatum in humans, current models present only mild symptoms that limits examination of potential therapeutics for eczema vaccinatum. The atopic dermatitis and eczema vaccinatum models we present here, are the first to simulate the severity of the diseases in humans. Indeed, dermatitic mice display persistent severe dermatitis, characterized by dry and inflamed skin with barrier dysfunction, epidermal hyperplasia and significant elevation of serum IgE. By exposing atopic dermatitis mice to ectromelia virus, we generated eczema vaccinatum that mimic the human disease better than known eczema vaccinatum models. Similarly to humans, eczematous mice displayed enlarged and disseminated skin lesions, which correlated with elevated viral load. Cidofovir and antiviral antibodies conferred protection even when treatment started at a late eczematous stage. Moreover, we are the first to demonstrate that despite a severe background of atopic dermatitis, modified vaccinia Ankara virus (MVA) vaccination protects against lethal ectromelia virus exposure. We finally show that protection by MVA vaccination is dependent on CD4⁺ T cells and is associated with significant activation of CD8⁺ cytotoxic T cells and induction of humoral immunity.

Cutaneous Deficiency of Filaggrin and STAT3 Exacerbates Vaccinia Disease In Vivo

Rationale

Defects in filaggrin and STAT3 are associated with atopic dermatitis (AD) and susceptibility to severe skin infection.

Methods

We evaluated skin infection with the current smallpox vaccine, ACAM-2000, in immunosuppressed mice with combined cutaneous deficiency in filaggrin and STAT3. In parallel, early events post-infection with ACAM-2000 were investigated in cultured keratinocytes in which filaggrin expression was knocked down via siRNA.

Results

Immunosuppressed, filaggrin-deficient mice, treated with the topical STAT3 inhibitor Stattic® prior to ACAM-2000 infection, demonstrated rapid weight loss, prolonged vaccinia burden in skin, and dermatitis. The TGF-β family ligand activin A was upregulated ten-fold in infected skin. Topically-applied ALK5/TGβR1 signaling inhibitor synergized with vaccinia immune globulin (VIG) to promote vaccinia clearance and limit weight loss. In cultured keratinocytes, filaggrin-directed siRNA inhibited programmed necrosis and inflammatory cytokine release induced by ACAM-2000, while viral growth was increased.

Conclusions

Our findings may point to a novel role for filaggrin in early antiviral responses in skin. In wounded skin with underlying barrier defects, chronically elevated activin A levels may contribute to skin remodeling and cutaneous pathogen persistence. Inhibition of ALK5/TGFβR1 signaling may provide a novel co-therapeutic approach, together with VIG, to limit cutaneous spread of vaccinia.

Filaggrin genotype and skin diseases independent of atopic dermatitis in childhood

BACKGROUND

Filaggrin gene (FLG) mutations compromise skin barrier functions and increase risk of atopic dermatitis. We aimed to study effects on other skin diseases using unique data from the Danish registers.

METHODS

FLG genotyping of a population-based sample of 1547 children with extracted DNA and information on skin diseases from the Danish National Birth Cohort and Health Register, with 18 years follow-up during years 1996-2013. Odds ratios (OR) and hazard ratios (HR) were estimated using logistic regression and Cox regression, respectively, and adjusted for physician-diagnosed atopic dermatitis.

RESULTS

FLG mutations were associated with increased risk of dry skin (OR 1.9, CI 1.1-3.1), and a decreased risk of fungal skin infections at age <18 months (OR 0.2, CI 0.1-0.8). There was no association with wart treatments (HR 1.0, CI 0.6-1.7). FLG mutations were associated with an increased risk of atopic dermatitis (OR 3.3, CI 2.1-5.3), dermatology consultations for allergy or rash (HR 2.2, CI 1.4-3.5), basic dermatology consultations at age <5 years (HR 2.2, CI 1.7-2.9), urticaria at age <18 months (OR 2.9, CI 1.0-7.9), and other rash at age <18 months (OR 2.1, CI 1.2-3.8).

CONCLUSIONS

FLG mutations may predispose to skin disease in young children including urticaria, and rash not recognized as atopic dermatitis although equally frequent. In clinical practice, FLG genotyping may help indicate the use of moisturizers to reduce skin problems.

Vaccination against Viruses

Most vaccines in use today are the result of empirical development. The mechanism of action of many vaccines in common use remains incompletely understood. Understanding how such vaccines protect is an ongoing subject of study using increasingly sophisticated immunological tools, such as B cell and T cell repertoire and transcriptome analysis. Such tools are also being applied to the design of vaccines against those viral targets that have evaded vaccine-mediated protection thus far. As basic immunological science intersects with the practicalities of assuring vaccine safety, tolerability, efficacy, and consistency in the clinic, the practical utility of more sophisticated immunological measures for vaccine development may be determined by whether they can be reduced to simply executed, highly standardized, reproducible assays with outcomes that have clear interpretations for vaccine development and use. Basic immunology, empirical vaccine testing, and regulatory science are all necessary contributors to developing the next generation of vaccines, including vaccines effective against the pathogens for which vaccines are not currently available.

Cytokine production associated with smallpox vaccine responses

Smallpox was eradicated 34 years ago due to the success of the smallpox vaccine; yet, the vaccine continues to be studied because of its importance in responding to potential biological warfare and the adverse events associated with current smallpox vaccines. Interindividual variations in vaccine response are observed and are, in part, due to genetic variation. In some cases, these varying responses lead to adverse events, which occur at a relatively high rate for the smallpox vaccine compared with other vaccines. Here, we aim to summarize the cytokine responses associated with smallpox vaccine response to date. Along with a description of each of these cytokines, we describe the genetic and adverse event data associated with cytokine responses to smallpox vaccination.

Filaggrin deficiency promotes the dissemination of cutaneously inoculated vaccinia virus

BACKGROUND

Eczema vaccinatum is a life-threatening complication of smallpox vaccination in patients with atopic dermatitis (AD) characterized by dissemination of vaccinia virus (VV) in the skin and internal organs. Mutations in the filaggrin (FLG) gene, the most common genetic risk factor for AD, confer a greater risk for eczema herpeticum in patients with AD, suggesting that it impairs the response to cutaneous viral infections.

OBJECTIVE

We sought to determine the effects of FLG deficiency on the response of mice to cutaneous VV inoculation.

METHODS

VV was inoculated by means of scarification of unsensitized skin or skin topically sensitized with ovalbumin in FLG-deficient flaky tail (ft/ft) mice or wild-type (WT) control mice. The sizes of primary and satellite skin lesions were measured, and hematoxylin and eosin staining was performed. VV genome copy numbers and cytokine mRNA levels were measured by using quantitative PCR.

RESULTS

VV inoculation in unsensitized skin of ft/ft mice, independent of the matted hair mutation, resulted in larger primary lesions, more abundant satellite lesions, heavier viral loads in internal organs, greater epidermal thickness, dermal cellular infiltration, and higher local Il17a, Il4, Il13, and Ifng mRNA levels than in WT control mice. VV inoculation at sites of topical ovalbumin application amplified all of these features in ft/ft mice but had no detectable effect in WT control mice. The number of satellite lesions and the viral loads in internal organs after cutaneous VV inoculation were significantly reduced in both unsensitized and topically sensitized ft/ftxIl17a(-/-) mice.

CONCLUSION

FLG deficiency predisposes to eczema vaccinatum. This is mediated primarily through production of IL-17A.

Development of eczema vaccinatum in atopic mouse models and efficacy of MVA vaccination against lethal poxviral infection

Smallpox vaccine based on live, replicating vaccinia virus (VACV) is associated with several potentially serious and deadly complications. Consequently, a new generation of vaccine based on non-replicating Modified vaccinia virus Ankara (MVA) has been under clinical development. MVA seems to induce good immune responses in blood tests, but it is impossible to test its efficacy in vivo in human. One of the serious complications of the replicating vaccine is eczema vaccinatum (EV) occurring in individuals with atopic dermatitis (AD), thus excluding them from all preventive vaccination schemes. In this study, we first characterized and compared development of eczema vaccinatum in different mouse strains. Nc/Nga, Balb/c and C57Bl/6J mice were epicutaneously sensitized with ovalbumin (OVA) or saline control to induce signs of atopic dermatitis and subsequently trans-dermally (t.d.) immunized with VACV strain Western Reserve (WR). Large primary lesions occurred in both mock- and OVA-sensitized Nc/Nga mice, while they remained small in Balb/c and C57Bl/6J mice. Satellite lesions developed in both mock- and OVA-sensitized Nc/Nga and in OVA-sensitized Balb/c mice with the rate 40–50%. Presence of mastocytes and eosinophils was the highest in Nc/Nga mice. Consequently, we have chosen Nc/Nga mice as a model of AD/EV and tested efficacy of MVA and Dryvax vaccinations against a lethal intra-nasal (i.n.) challenge with WR, the surrogate of smallpox. Inoculation of MVA intra-muscularly (i.m.) or t.d. resulted in no lesions, while inoculation of Dryvax t.d. yielded large primary and many satellite lesions similar to WR. Eighty three and 92% of mice vaccinated with a single dose of MVA i.m. or t.d., respectively, survived a lethal i.n. challenge with WR without any serious illness, while all Dryvax-vaccinated animals survived. This is the first formal prove of protective immunity against a lethal poxvirus challenge induced by vaccination with MVA in an atopic organism.

Atopic dermatitis: skin-directed management

Atopic dermatitis is a common inflammatory skin condition characterized by relapsing eczematous lesions in a typical distribution. It can be frustrating for pediatric patients, parents, and health care providers alike. The pediatrician will treat the majority of children with atopic dermatitis as many patients will not have access to a pediatric medical subspecialist, such as a pediatric dermatologist or pediatric allergist. This report provides up-to-date information regarding the disease and its impact, pathogenesis, treatment options, and potential complications. The goal of this report is to assist pediatricians with accurate and useful information that will improve the care of patients with atopic dermatitis.

Vaccinia virus induces rapid necrosis in keratinocytes by a STAT3-dependent mechanism

RATIONALE

Humans with a dominant negative mutation in STAT3 are susceptible to severe skin infections, suggesting an essential role for STAT3 signaling in defense against cutaneous pathogens.

METHODS

To focus on innate antiviral defenses in keratinocytes, we used a standard model of cutaneous infection of severe combined immunodeficient mice with the current smallpox vaccine, ACAM-2000. In parallel, early events post-infection with the smallpox vaccine ACAM-2000 were investigated in cultured keratinocytes of human and mouse origin.

RESULTS

Mice treated topically with a STAT3 inhibitor (Stattic) developed larger vaccinia lesions with higher virus titers and died more rapidly than untreated controls. Cultured human and murine keratinocytes infected with ACAM-2000 underwent rapid necrosis, but when treated with Stattic or with inhibitors of RIP1 kinase or caspase-1, they survived longer, produced higher titers of virus, and showed reduced activation of type I interferon responses and inflammatory cytokines release. Treatment with inhibitors of RIP1 kinase and STAT3, but not caspase-1, also reduced the inflammatory response of keratinocytes to TLR ligands. Vaccinia growth properties in Vero cells, which are known to be defective in some antiviral responses, were unaffected by inhibition of RIP1K, caspase-1, or STAT3.

CONCLUSIONS

Our findings indicate that keratinocytes suppress the replication and spread of vaccinia virus by undergoing rapid programmed cell death, in a process requiring STAT3. These data offer a new framework for understanding susceptibility to skin infection in patients with STAT3 mutations. Interventions which promote prompt necroptosis/pyroptosis of infected keratinocytes may reduce risks associated with vaccination with live vaccinia virus.

Blocking pathogen transmission at the source: reservoir targeted OspA-based vaccines against Borrelia burgdorferi

Control strategies are especially challenging for microbial diseases caused by pathogens that persist in wildlife reservoirs and use arthropod vectors to cycle amongst those species. One of the most relevant illnesses that pose a direct human health risk is Lyme disease; in the US, the Centers for Disease Control and Prevention recently revised the probable number of cases by 10-fold, to 300,000 cases per year. Caused by Borrelia burgdorferi, Lyme disease can affect the nervous system, joints and heart. No human vaccine is approved by the Food and Drug Administration. In addition to novel human vaccines, new strategies for prevention of Lyme disease consist of pest management interventions, vector-targeted vaccines and reservoir-targeted vaccines. However, even human vaccines can not prevent Lyme disease expansion into other geographical areas. The other strategies aim at reducing tick density and at disrupting the transmission of B. burgdorferi by targeting one or more key elements that maintain the enzootic cycle: the reservoir host and/or the tick vector. Here, I provide a brief overview of the application of an OspA-based wildlife reservoir targeted vaccine aimed at reducing transmission of B. burgdorferi and present it as a strategy for reducing Lyme disease risk to humans.

Transcutaneous yellow fever vaccination of subjects with or without atopic dermatitis

BACKGROUND

Atopic dermatitis (AD) is a common inflammatory skin disease with a global prevalence ranging from 3% to 20%. Patients with AD have an increased risk for complications after viral infection (eg, herpes simplex virus), and vaccination of patients with AD with live vaccinia virus is contraindicated because of a heightened risk of eczema vaccinatum, a rare but potentially lethal complication associated with smallpox vaccination.

OBJECTIVE

We sought to develop a better understanding of immunity to cutaneous viral infection in patients with AD.

METHODS

In a double-blind randomized study we investigated the safety and immunogenicity of live attenuated yellow fever virus (YFV) vaccination of nonatopic subjects and patients with AD after standard subcutaneous inoculation or transcutaneous vaccination administered with a bifurcated needle. Viremia, neutralizing antibody, and antiviral T-cell responses were analyzed for up to 30 days after vaccination.

RESULTS

YFV vaccination administered through either route was well tolerated. Subcutaneous vaccination resulted in higher seroconversion rates than transcutaneous vaccination but elicited similar antiviral antibody levels and T-cell responses in both the nonatopic and AD groups. After transcutaneous vaccination, both groups mounted similar neutralizing antibody responses, but patients with AD demonstrated lower antiviral T-cell responses by 30 days after vaccination. Among transcutaneously vaccinated subjects, a significant inverse correlation between baseline IgE levels and the magnitude of antiviral antibody and CD4(+) T-cell responses was observed.

CONCLUSIONS

YFV vaccination of patients with AD through the transcutaneous route revealed that high baseline IgE levels provide a potential biomarker for predicting reduced virus-specific immune memory after transcutaneous infection with a live virus.

Orthopoxvirus inhibitors that are active in animal models: an update from 2008 to 2012

Antiviral agents are being sought as countermeasures for the potential deliberate release of smallpox (variola) and monkeypox viruses, for the treatment of naturally acquired monkeypox virus infections, and as therapy for complications due to smallpox (live-attenuated vaccinia virus) vaccination or accidental infection after exposure to vaccinated persons. Reviews of the scientific literature spanning 1950-2008 have documented the progress made in developing small-animal models of poxvirus infection and identifying novel antiviral agents. Compounds of considerable interest include cidofovir, CMX001 and ST-246® (tecovirimat; SIGA Technologies, NY, USA). New inhibitors have been identified since 2008, most of which do not exhibit the kind of potency and selectivity required for drug development. Two promising agents include 4'-thioidoxuridine (a nucleoside analog) and mDEF201 (an adenovirus-vectored interferon). Compounds that have been effectively used in combination studies include vaccinia immune globulin, cidofovir, ST-246 and CMX001. In the future there may be an increase in experimental work using active compounds in combination.