16 research outputs found

    Robust T cell immunity in convalescent individuals with asymptomatic or mild COVID-19

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    SARS-CoV-2-specific memory T cells will likely prove critical for long-term immune protection against COVID-19. Here, we systematically mapped the functional and phenotypic landscape of SARS-CoV-2-specific T cell responses in unexposed individuals, exposed family members, and individuals with acute or convalescent COVID-19. Acute-phase SARS-CoV-2-specific T cells displayed a highly activated cytotoxic phenotype that correlated with various clinical markers of disease severity, whereas convalescent-phase SARS-CoV-2-specific T cells were polyfunctional and displayed a stem-like memory phenotype. Importantly, SARS-CoV-2-specific T cells were detectable in antibody-seronegative exposed family members and convalescent individuals with a history of asymptomatic and mild COVID-19. Our collective dataset shows that SARS-CoV-2 elicits broadly directed and functionally replete memory T cell responses, suggesting that natural exposure or infection may prevent recurrent episodes of severe COVID-19

    Cutaneous leishmaniasis : treatment and genetic mechanisms affecting outcome

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    Leishmaniasis is a neglected parasitic disease and a rare diagnosis in non-endemic countries in Europe. Migration, geopolitical conflicts and climate change have increased awareness of this infection in Europe, as more patients with leishmaniasis are admitted to health care. Pentavalent antimonial has been used for decades as the first-line treatment regardless of clinical manifestations and Leishmania species. Treatment failures and relapses, possibly due to drug resistance, in combination with drug toxicity, have created the need for new treatment regimens. Today, several alternatives are available and recommended depending on the clinical manifestation, Leishmania spp. and geographic region. The objectives of this thesis were to: - Investigate the genome of Leishmania tropica, focusing on genetic diversity and correlate it with previous antimonial exposure - Study treatment and outcome of leishmaniasis in non-endemic countries in Europe In the first two studies, Study I and Study II, we investigated the genome of 22 L. tropica isolates and described genetic diversity and genetic mechanisms for adaptation to environmental changes and drug pressure. Among the isolates, we observed extensive genetic variation with high heterozygosity and aneuploidy, and evidence of genetic exchange within and among isolates. The latter indicates hybridisation and a possible presence of sexual or parasexual mechanisms. It may be postulated that the high genetic diversity and recombination explain the challenges seen when treating cutaneous leishmaniasis caused by L. tropica. L. tropica has several genetic mechanisms to adapt to environmental changes. We observed a higher non-synonymous single nucleotide polymorphism rate in the isolates from Syria at the H locus, compared with in isolates from Afghanistan and Iran. This locus has several mechanisms connected to drug resistance in other Leishmania spp. No increased copy number variation was observed in genes correlated with drug resistance. Instead, among isolates previously exposed to antimonial multiple genes involved in essential cellular functions were amplified, indicating several genetic mechanisms involved in surviving drug pressure. In Studies III and IV, we evaluated the treatments and outcome in non-endemic countries in Europe. All patients with leishmaniasis in Sweden between 1996-2016 were included in Study III. The number of cases increased during 2013-2016 in Sweden, mainly due to increased migration from endemic areas. L. tropica was the most common species among patients with cutaneous leishmaniasis in the Swedish cohort. Treatment was started within the first month after suspicion of leishmaniasis in 66% of the patients and the overall cure rate was 70%, suggesting a high awareness within the health care system in Sweden. In the European study, cutaneous leishmaniasis patients with L. major or L. tropica were evaluated with regard to treatment and outcome. Patients infected with L. major were mainly infected in North Africa, when visiting family and friends and patients with L. tropica were mainly migrants from Syria. Treatment with pentavalent antimony had a cure rate in line with those of previous studies, as did treatment with liposomal amphotericin B and cryotherapy. All patients with L. major were cured within the year after diagnosis compared with L. tropica where 21 % patients relapsed within the first year. This thesis has aimed to enhance the knowledge and understanding of cutaneous leishmaniasis. By analysing the complex L. tropica genome, we tried to better understand intra- and inter-chromosomal changes in diversity driven by recombination and aneuploidy and correlate the single nucleotide polymorphism and copy number variation to previous antimony exposure. Evaluating treatments, new drugs and treatment regimens, and outcome in non-endemic countries provides important information for future guidelines. By combining the two perspectives in the leishmaniasis research field, we hoped to enhance the understanding of the complex genetic mechanisms used by Leishmania to survive antimonial treatment

    Cutaneous, mucocutaneous and visceral leishmaniasis in Sweden from 1996-2016 : A retrospective study of clinical characteristics, treatments and outcomes 11 Medical and Health Sciences 1103 Clinical Sciences

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    Background: Leishmaniasis is a neglected and poorly reported parasitic infection transmitted by sand flies in tropical and subtropical regions. Knowledge about leishmaniasis has become important in non-endemic countries due to increased migration and travel. Few studies of the clinical management of cutaneous, mucocutaneous and visceral leishmaniasis in non-endemic regions have been published to date. In this study, we aimed to evaluate patient characteristics, clinical manifestations and treatments of leishmaniasis in Sweden, over a 20-year period. Methods: A retrospective observational nationwide study was performed using medical records of patients diagnosed with leishmaniasis in Sweden from 1996 to 2016. Cases with culture and polymerase chain reaction verified leishmaniasis were identified at the Public Health Agency of Sweden. Results: In total, 165 cases of leishmaniasis were diagnosed from 1996 to 2016. Medical records from 156 patients (95%) were available for review and included in the study. Cutaneous leishmaniasis was the dominant manifestation (n = 149, 96%), and in 66 patients (44%) cutaneous leishmaniasis was due to Leishmania tropica. Other manifestations were mucocutaneous (n = 4, 3%), visceral (n = 2, 1%) and post-kala-azar dermal leishmaniasis (n = 1, 1%). During this time period, the number of cases increased, especially after 2013. Most patients (n = 81, 52%) were migrants who were infected in their countries of origin (from 2013 to 2016, mainly Syria or Afghanistan). Other groups were Swedish tourists (25%) and returning workers (13%). The time from collection of the diagnostic sample to the start of treatment was less than one month in 81 (66%) patients and under three months in 124 patients (96%). Among the 149 patients with cutaneous leishmaniasis, 125 patients received antileishmanial treatment, and in 88 of these patients (70%) cure was achieved, regardless of treatment. Conclusions: The number of leishmaniasis cases diagnosed in Sweden increased between 1996 and 2016, mainly in migrants from endemic countries. Although leishmaniasis is a rare disease in Sweden, patients appear to be diagnosed early and treated according to current European guidelines, resulting in an overall high cure rate

    Recurrent Herpes Zoster Ophthalmicus in a Patient With a Novel Toll-Like Receptor 3 Variant Linked to Compromised Activation Capacity in Fibroblasts

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    BACKGROUND: Herpes zoster ophthalmicus occurs primarily in elderly or immunocompromised individuals after reactivation of varicella zoster virus (VZV). Recurrences of zoster ophthalmicus are uncommon because the reactivation efficiently boosts anti-VZV immunity. A 28-year-old female presented to our clinic with a history of multiple recurrences of zoster ophthalmicus. METHODS: Whole-exome sequencing (WES), analyses of VZV T-cell immunity, and pathogen recognition receptor function in primary antigen-presenting cells (APCs) and fibroblasts were performed. RESULTS: Normal VZV-specific T-cell immunity and antibody response were detected. Whole-exome sequencing identified a heterozygous nonsynonymous variant (c.2324C > T) in the Toll-like receptor 3 (TLR3) gene resulting in formation of a premature stop-codon. This alteration could potentially undermine TLR3 signaling in a dominant-negative fashion. Therefore, we investigated TLR3 signaling responses in APCs and fibroblasts from the patient. The APCs responded efficiently to stimulation with TLR3 ligands, whereas the responses from the fibroblasts were compromised. CONCLUSIONS: We report a novel TLR3 variant associated with recurrent zoster ophthalmicus. Toll-like receptor 3 responses that were unaffected in APCs but diminished in fibroblasts are in line with previous reports linking TLR3 deficiency with herpes simplex virus encephalitis. Mechanisms involving compromised viral sensing in infected cells may thus be central to the described immunodeficiency

    Comprehensive proteomics and meta-analysis of COVID-19 host response

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    Abstract COVID-19 is characterised by systemic immunological perturbations in the human body, which can lead to multi-organ damage. Many of these processes are considered to be mediated by the blood. Therefore, to better understand the systemic host response to SARS-CoV-2 infection, we performed systematic analyses of the circulating, soluble proteins in the blood through global proteomics by mass-spectrometry (MS) proteomics. Here, we show that a large part of the soluble blood proteome is altered in COVID-19, among them elevated levels of interferon-induced and proteasomal proteins. Some proteins that have alternating levels in human cells after a SARS-CoV-2 infection in vitro and in different organs of COVID-19 patients are deregulated in the blood, suggesting shared infection-related changes.The availability of different public proteomic resources on soluble blood proteome alterations leaves uncertainty about the change of a given protein during COVID-19. Hence, we performed a systematic review and meta-analysis of MS global proteomics studies of soluble blood proteomes, including up to 1706 individuals (1039 COVID-19 patients), to provide concluding estimates for the alteration of 1517 soluble blood proteins in COVID-19. Finally, based on the meta-analysis we developed CoViMAPP, an open-access resource for effect sizes of alterations and diagnostic potential of soluble blood proteins in COVID-19, which is publicly available for the research, clinical, and academic community

    Treatment outcome of imported cutaneous leishmaniasis among travelers and migrants infected with Leishmania major and Leishmania tropica: a retrospective study in European centers 2013 to 2019

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    International audienceOBJECTIVES: Cutaneous leishmaniasis (CL) in Asia, Northern, and Sub-Saharan Africa is mainly caused by Leishmania major and Leishmania tropica. We describe and evaluate the treatment outcome of CL among travelers and migrants in Europe.METHODS: We conducted a retrospective study of parasitological confirmed CL cases caused by L. major and L. tropica during 2013-2019 in Europe. Data were collected from medical records and databases within the LeishMan network.RESULTS: Of 206 included cases of CL, 75 were identified as L. major and 131 as L. tropica. Of patients with L. tropica infection, 80% were migrants, whereas 53% of patients with L. major infection had been visiting friends and relatives. Among patients with L. tropica, 48% were younger than 15 years. Pentavalent antimony cured 73% (L. major) and 78% (L. tropica) of patients. The cure rate for intralesional administration was 86% and 67% for systemic, on L. tropica. Liposomal amphotericin B had a cure rate of 44-63%. CONCLUSION: L. major infections were mostly found in individuals visiting friends and relatives, whereas L. tropica were mainly identified in migrants. No patients with L. major relapsed. Pentavalent antimony, liposomal amphotericin B, and cryotherapy had cure rates in accordance with previous studies

    Epidemiological and clinical characteristics of patients with monkeypox in the GeoSentinel Network: a cross-sectional study

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    © 2022 Elsevier Ltd. All rights reserved.Background: The early epidemiology of the 2022 monkeypox epidemic in non-endemic countries differs substantially from the epidemiology previously reported from endemic countries. We aimed to describe the epidemiological and clinical characteristics among individuals with confirmed cases of monkeypox infection. Methods: We descriptively analysed data for patients with confirmed monkeypox who were included in the GeoSentinel global clinical-care-based surveillance system between May 1 and July 1 2022, across 71 clinical sites in 29 countries. Data collected included demographics, travel history including mass gathering attendance, smallpox vaccination history, social history, sexual history, monkeypox exposure history, medical history, clinical presentation, physical examination, testing results, treatment, and outcomes. We did descriptive analyses of epidemiology and subanalyses of patients with and without HIV, patients with CD4 counts of less than 500 cells per mm3 or 500 cells per mm3 and higher, patients with one sexual partner or ten or more sexual partners, and patients with or without a previous smallpox vaccination. Findings: 226 cases were reported at 18 sites in 15 countries. Of 211 men for whom data were available, 208 (99%) were gay, bisexual, or men who have sex with men (MSM) with a median age of 37 years (range 18-68; IQR 32-43). Of 209 patients for whom HIV status was known, 92 (44%) men had HIV infection with a median CD4 count of 713 cells per mm3 (range 36-1659; IQR 500-885). Of 219 patients for whom data were available, 216 (99%) reported sexual or close intimate contact in the 21 days before symptom onset; MSM reported a median of three partners (IQR 1-8). Of 195 patients for whom data were available, 78 (40%) reported close contact with someone who had confirmed monkeypox. Overall, 30 (13%) of 226 patients were admitted to hospital; 16 (53%) of whom had severe illness, defined as hospital admission for clinical care rather than infection control. No deaths were reported. Compared with patients without HIV, patients with HIV were more likely to have diarrhoea (p=0·002), perianal rash or lesions (p=0·03), and a higher rash burden (median rash burden score 9 [IQR 6-21] for patients with HIV vs median rash burden score 6 [IQR 3-14] for patients without HIV; p<0·0001), but no differences were identified in the proportion of men who had severe illness by HIV status. Interpretation: Clinical manifestations of monkeypox infection differed by HIV status. Recommendations should be expanded to include pre-exposure monkeypox vaccination of groups at high risk of infection who plan to engage in sexual or close intimate contact.US Centers for Disease Control and Prevention, International Society of Travel Medicineinfo:eu-repo/semantics/publishedVersio

    Cutaneous and mucocutaneous leishmaniasis in travellers and migrants: a 20-year GeoSentinel Surveillance Network analysis

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    BACKGROUND: Cutaneous leishmaniasis (CL) may be emerging among international travellers and migrants. Limited data exist on mucocutaneous leishmaniasis (MCL) in travellers. We describe the epidemiology of travel-associated CL and MCL among international travellers and immigrants over a 20-year period through descriptive analysis of GeoSentinel data. METHODS: Demographic and travel-related data on returned international travellers diagnosed with CL or MCL at a GeoSentinel Surveillance Network site between 1 September 1997 and 31 August 2017 were analysed. RESULTS: A total of 955 returned travellers or migrants were diagnosed with travel-acquired CL (n = 916) or MCL during the study period, of whom 10% (n = 97) were migrants. For the 858 non-migrant travellers, common source countries were Bolivia (n = 156, 18.2%) and Costa Rica (n = 97, 11.3%), while for migrants, they were Syria (n = 34, 35%) and Afghanistan (n = 22, 22.7%). A total of 99 travellers (10%) acquired their disease on trips of ≤ 2 weeks. Of 274 cases for which species identification was available, Leishmania Viannia braziliensis was the most well-represented strain (n = 117, 42.7%), followed by L. major (n = 40, 14.6%) and L. V. panamensis (n = 38, 13.9%). Forty cases of MCL occurred, most commonly in tourists (n = 29, 72.5%) and from Bolivia (n = 18, 45%). A total of 10% of MCL cases were acquired in the Old World. CONCLUSIONS: Among GeoSentinel reporting sites, CL is predominantly a disease of tourists travelling mostly to countries in Central and South America such as Bolivia where risk of acquiring L. V. braziliensis and subsequent MCL is high. The finding that some travellers acquired leishmaniasis on trips of short duration challenges the common notion that CL is a disease of prolonged travel. Migrants from areas of conflict and political instability, such as Afghanistan and Syria, were well represented, suggesting that as mass migration of refugees continues, CL will be increasingly encountered in intake countries

    Travel-related infections presenting in Europe: A 20-year analysis of EuroTravNet surveillance data.

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    Funder: Centers for Disease Control and PreventionBACKGROUND: Disease epidemiology of (re-)emerging infectious diseases is changing rapidly, rendering surveillance of travel-associated illness important. METHODS: We evaluated travel-related illness encountered at EuroTravNet clinics, the European surveillance sub-network of GeoSentinel, between March 1, 1998 and March 31, 2018. FINDINGS: 103,739 ill travellers were evaluated, including 11,239 (10.8%) migrants, 89,620 (86.4%) patients seen post-travel, and 2,880 (2.8%) during and after travel. Despite increasing numbers of patient encounters over 20 years, the regions of exposure by year of clinic visits have remained stable. In 5-year increments, greater proportions of patients were migrants or visiting friends and relatives (VFR); business travel-associated illness remained stable; tourism-related illness decreased. Falciparum malaria was amongst the most-frequently diagnosed illnesses with 5,254 cases (5.1% of all patients) and the most-frequent cause of death (risk ratio versus all other illnesses 2.5:1). Animal exposures requiring rabies post-exposure prophylaxis increased from 0.7% (1998-2002) to 3.6% (2013-2018). The proportion of patients with seasonal influenza increased from zero in 1998-2002 to 0.9% in 2013-2018. There were 44 cases of viral haemorrhagic fever, most during the past five years. Arboviral infection numbers increased significantly as did the range of presenting arboviral diseases, dengue and chikungunya diagnoses increased by 2.6% and 1%, respectively. INTERPRETATION: Travel medicine must adapt to serve the changing profile of travellers, with an increase in migrants and persons visiting relatives and friends and the strong emergence of vector-borne diseases, with potential for further local transmission in Europe. FUNDING: This project was supported by a cooperative agreement (U50CK00189) between the Centers for Disease Control and Prevention to the International Society of Travel Medicine (ISTM) and funding from the ISTM and the Public Health Agency of Canada
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