Trypanosoma cruzi infection in a non-endemic country: epidemiological and clinical profile

Chagas disease has been increasingly diagnosed in non-endemic countries. This is a prospective observational study performed at the Tropical Medicine Units of the International Health Program of the Catalan Health Institute, Barcelona (PROgrama de Salud Internacional del Instituto Catalán de la Salud, PROSICS Barcelona, Spain), that includes all patients with Chagas disease who attended from June 2007 to May 2012. Clinical and epidemiological data were collected. Overall, 1274 patients were included, the mean age of the patients was 37.7 years, 67.5% were women and 97% came from Bolivia. Thirteen patients had immunosuppressive conditions. The prevalence of cardiac involvement was 16.9%, lower than in previous studies performed in endemic areas (20–60%). Cardiac alterations were found in 33.8% of symptomatic and 14.1% of asymptomatic patients. The prevalence of digestive involvement was 14.8%. The rate of digestive involvement is very different among previous studies because of different diagnostic tools and strategies used. Barium enema alterations were found in 21.4% of symptomatic and 10.3% of asymptomatic patients, and oesophageal alterations were found in 3.7% of symptomatic and in 2.3% of asymptomatic patients. As shown in previous studies, Chagas disease in non-endemic countries affects younger patients and has lower morbidity.     

Visceral leishmaniasis: a threat to immunocompromised patients in non-endemic areas?

Visceral leishmaniasis is rare in western Europe, but may be life-threatening in immunocompromised patients. It is therefore important to understand the incidence of the disease in a non-endemic area and its relationship with immunosuppressive conditions. Between 1990 and 2005, 12 patients were diagnosed with leishmaniasis at Basel University Hospital, Switzerland. Eleven presented with visceral symptoms and ten had an underlying immunosuppressive condition. Since increasing numbers of immunosuppressed patients have a history of travel to endemic countries, an association of visceral leishmaniasis with cellular immunosuppression (other than that associated with human immunodeficiency virus) might become more frequent in non-endemic areas.     

Detection of asymptomatic Leishmania donovani in healthy voluntary blood donors

ObjectiveTo check incidence of Asymptomatic Leishmania donovani reporting to Armed Forces Institute of Transfusion Rawalpindi.Material and MethodsTwo thousand (n = 2000) consecutive healthy voluntary blood donors were tested for 18 s rRNA by Real time Polymerase chain reaction. One thousand (n = 1000) subject’s permanent resident of Azad Kashmir along with a thousand (n = 1000) healthy voluntary blood donors from rest of Pakistan were included. The study was carried out over a period of three months Jun – Aug 2020.ResultsTotal of 2000 blood donors were enrolled in the study, all were males with age ranging from 16 to 60 years. Stratification based on residence, 1000 (50 %) resided in the Azad kashmir, 349 (17.45 %) were from Islamabad and Rawalpindi, 541 (27.05 %) from Punjab mainly residing in Lahore and Multan, 110 (5.5 %) were from other cities of Pakistan. Grouping on the basis of age, 55.25 % ( n = 1105) of the donors were 16–25 years old, 19.45 % ( n = 389) were in age range of 26–40 years old, 15.55 % ( n = 311) were 41–50 years old and 9.75 % ( n = 195) 51–60 years old. No donor was diagnosed as an asymptomatic carrier.ConclusionScreening of blood donors for Leishmania donovani is not recommended.     

European survey of glycopeptide susceptibility in Staphylococcus spp.

Objectives: To reassess the relative potencies of teicoplanin and vancomycin following several years of clinical usage.
Methods: The glycopeptide susceptibilities of clinical isolates of staphylococci collected from 70 hospitals in 1995 were determined using NCCLS (National Committee for Clinical Laboratory Standards) methods.
Results: In total, 2885 isolates of Staphylococcus aureus and 1480 isolates of coagulase-negative staphylococci were collected. S. aureus was significantly less susceptible to vancomycin (MIC₅₀ 1 mg/L) than teicoplanin (MIC₅₀ 0.5 mg/L), but the reverse was the case for S. haemolyticus and S. epidermidis . No S. aureus isolate was resistant (≥32 mg/L) to either glycopeptide, but nine isolates of coagulase-negative staphylococci had an MIC of teicoplanin of 32 mg/L. Respiratory isolates of S. aureus were less susceptible to glycopeptides than those from other sites. Staphylococci from Belgium and Italy were less susceptible to teicoplanin than isolates from other countries.
Conclusions: This European survey shows that in 10 years of clinical use there have been no major changes in the susceptibility of staphylococci to the glycopeptides.     

Asymptomatic carriage of Leishmania in family members of patients with visceral leishmaniasis in Central Tunisia

Introduction

In Tunisia, asymptomatic carriage of Leishmania is poorly documented.

Objective

The aim of the present study was to estimate the frequency of asymptomatic infection among the family members of patients with patent visceral leishmaniasis by using the Western blotting kit based on 14 and 16 kDa bands.

Material and methods

We tested 94 sera collected from 24 patients with patent visceral leishmaniasis and 70 from their families’ members.

Results

The rate of seropositivity was 100% in the group of patients and 54.3% in the group of families’ members. The analysis of the Western blotting patterns showed that the 33 kDa, 24 kDa and to a lesser extent the 22 kDa band were very indicative of patent visceral leishmaniasis in contrast to asymptomatic infection where these bands were very rarely detected.

Conclusion

The results reported herein showed the high frequency of asymptomatic carriers of Leishmania among the families’ members of visceral leishmaniasis cases and the usefulness of the Western blotting as a screening technique and in distinguishing between patent visceral leishmaniasis and the asymptomatic carriage of Leishmania.     

Emergence of sandflies (Phlebotominae) in Austria, a Central European country

The possible existence of autochthonous sandfly populations in Central Europe north of the Alps has long been excluded. However, in the past years, sandflies have been documented in Germany, Belgium, and recently, also in Austria, close to the Slovenian border. Moreover, autochthonous human Leishmania and Phlebovirus infections have been reported in Central Europe, particularly in Germany. From 2010 to 2012, sandfly trapping (740 trap nights) was performed at 53 different capture sites in Austria using battery-operated CDC miniature light traps. Sites were chosen on the basis of their climate profile in the federal states Styria, Burgenland, and Lower Austria. Sandfly specimens found were transferred to 70 % ethanol for conservation. Identification was based on morphological characters of the male genitalia and the female spermathecae, respectively. Altogether, 24 specimens, 22 females and 2 males, all identified as Phlebotomus (Transphlebotomus) mascittii Grassi, 1908, were found at six different sampling sites in all three federal states investigated. The highest number of catches was made on a farm in Lower Austria. Altogether, the period of sandfly activity in Austria was shown to be much longer than presumed, the earliest capture was made on July 3rd and the latest on August 28th. Sandflies have been autochthonous in Austria in small foci probably for long, but in the course of global warming, further spreading may be expected. Although P. mascittii is only an assumed vector of Leishmania spp.—data on its experimental transmission capacity are still lacking—the wide distribution of sandflies in Austria, a country thought to be free of sandflies, further supports a potential emergence of sandflies in Central Europe. This is of medical relevance, not only with respect to the transmission of Leishmania spp. for which a reservoir is given in dogs, but also with respect to the phleboviruses.     

Cutaneous leishmaniasis: an emerging infection in a non-endemic area and a brief update

We report here the emergence of a new focus of cutaneous leishmaniasis (CL) due to Leishmania tropica (L. tropica) in the Ajmer city of Rajasthan, India, a previously non-endemic area. Between January-February 2006, 13 new indigenously acquired cases of CL were diagnosed among the patients attending the Skin and STD department, JLN Hospital, Ajmer. The diagnosis was based on clinical presentation, demonstration of amastigotes (LT bodies) in Giemsa stained smear of the lesion and response to intralesional / local anti-leishmanial drug therapy. In addition, culture of the promastigote forms of L. tropica from the lesion was successfully attempted in four of the smear negatives cases. By retrospective analysis, 23 new indigenous cases of CL have been diagnosed in the same setting during the period January 2004 - December 2005, based on clinical and therapeutic response alone. There was no clear-cut history of sandfly bite and travel outside the district or state to endemic area in any of the cases. However, all of them came from a common residential area (famous dargah of Ajmer) and the peak incidence was seen in January, four months after the famous Urs fair of Ajmer, the location was urban and the lesions were characteristic of L. tropica. Therefore, the disease is suspected to be anthroponotic. These features are suggestive of a common mode of transmission, source and/or vector signalling introduction of this infection into a non-endemic area.     

Clinical pleiomorphism in human leishmaniases, with special mention of asymptomatic infection

This review gives an update of current knowledge on the clinical pleiomorphism of Leishmania, with a special emphasis on the case of asymptomatic carriage. The first part describes the numerous unusual expressions of the disease that occur besides the classic (visceral, cutaneous, and mucocutaneous) forms of leishmaniases. The second part deals with progress in the understanding of disease outcome in humans, and the possible future approaches to improve our knowledge in the field. The third part highlights the role of the too often neglected asymptomatic carrier compartment. This group could be key to understanding infraspecific differences in virulence and pathogenicity of the parasite, as well as identifying the genetic determinants involved in the expression of the disease.     

Episomal and stable expression of the luciferase reporter gene for quantifying Leishmania spp. infections in macrophages and in animal models

We have expressed the reporter firefly luciferase gene (LUC) in Leishmania donovani and Leishmania major either as part of episomal vectors or integrated into the parasite genome under the control of their respective ribosomal promoter regions. An excellent linear correlation between parasite number and luciferase activity was observed with all the transfectants. LUC-expressing recombinant parasites were useful to monitor Leishmania spp. infections in macrophages or in animal models. For prolonged growth in absence of drug selection, such as within animal models, quantitation of parasites is more reliable when the reporter gene LUC is stably integrated in the parasite genome. These recombinant strains should be useful tools to monitor Leishmania growth under a number of conditions.     

Evidence of Rickettsia spp. infection in Sweden: a clinical, ultrastructural and serological study

Sweden is an area potentially endemic for spotted fever rickettsioses. Rickettsia helvetica has been isolated from its tick vector Ixodes ricinus, and in a handful of cases linked to human disease. This study demonstrates for the first time in Sweden the transmission of rickettsial infection after a tick bite and the attack rate in an endemic area. We present three cases of documented rickettsial infection and a prospective serological study of Swedish recruits who were trained in the area where the patients lived and showed seroconversion to spotted fever rickettsiae. All patients showed a four-fold increase in antibody titer to the spotted fever rickettsia, R. helvetica, and immunohistochemical examination revealed rickettsia-like organisms in the walls of skin capillaries and veins. Electron microscopy showed organisms resembling R. helvetica and immunogold labeling with two anti-rickettsial antibodies demonstrated specific labeling of the rickettsial organisms in the skin biopsy specimens. Eight of the thirty-five recruits showed a four-fold increase in IgG titer reflecting a high rate of exposure. The results of this study demonstrate that spotted fever rickettsioses should be taken into consideration in the diagnosis of tick-transmitted infections in Sweden.     

Clinical and laboratory profile of trichinellosis from a non-endemic country

Trichinellosis is a zoonotic parasitic infection caused by nematodes of the genus Trichinella. Humans mostly get infected by eating raw/under-cooked pork. In India, it has been reported mostly as sporadic cases especially from North Eastern and Eastern part of country.In this study, we retrospectively analyzed the socio-demographic pattern, clinical presentation, laboratory profile and treatment response in Trichinella-infected patients visiting our tertiary care center which mainly caters to patients from North India. For this retrospective laboratory-based analysis, patients diagnosed on the basis of positive anti-Trichinella IgG antibodies between 1^st June 2008, and 31^st May 2019 were included.A total of 11 positive trichinellosis cases were detected, of whom majority were children who presented with history of fever, gastrointestinal symptoms, myalgia, eosinophilia along with hepatomegaly and pulmonary manifestations. No CNS involvement was seen in any of the patients although it is commonly associated with Trichinella infection. All patients recovered uneventfully after antihelminthic treatment.     

Leishmania infantum-specific T cell lines derived from asymptomatic dogs that lyse infected macrophages in a major histocompatibility complex-restricted manner

Protective immunity to leishmaniasis has been demonstrated in murine models to be mediated by T cells and the cytokines they produce. We have previously shown that resistance to experimental Leishmania infantum infection in the dog, a natural host and reservoir of the parasite, is associated with the proliferation of peripheral blood mononuclear cells (PBMC) to parasite antigen and to the production of interleukin-2 and tumour necrosis factor. In this study we show that PBMC from asymptomatic experimentally infected dogs produce interferon-γ upon parasite antigen-specific stimulation, whereas lymphocytes from symptomatic dogs do not. In addition, we report for the first time the lysis of L. infantum-infected macrophages by PBMC from asymptomatic dogs and by parasite-specific T cell lines derived from these animals. These T cell lines were generated by restimulation in vitro with parasite soluble antigen and irradiated autologous PBMC as antigen-presenting cells. We show that lysis of infected macrophages by T cell lines is major histocompatibility complex restricted. Characterization of parasite-specific cytotoxic T cell lines revealed that the responding cells are CD8⁺. However, for some animals, CD4⁺ T cells that lyse infected macrophages were also found. In contrast to asymptomatic dogs, lymphocytes from symptomatic dogs failed to proliferate and produce interferon-γ after Leishmania antigen stimulation in vitro and were not capable of lysing infected macrophages. These results suggest that both the production of interferon-γ and the destruction of the parasitized host cells by Leishmania-specific T cells play an important role in resistance to visceral leishmaniasis.     

Natural and acquired resistance to Leishmania: cellular activation by Leishmania aethiopica of mononuclear cells from unexposed individuals is through the stimulation of natural killer (NK) cells.

Cells from normal non-Leishmania-exposed individuals could respond in vitro by proliferation and interferon-gamma (IFN-gamma) production to Leishmania aethiopica stimulation. The main cell type that appeared to be activated following such stimulation was CD3-, CD16+/56+, i.e. NK cells. Of the few CD3+ cells responding, an involvement of CD8+ cells was evident in the absence of activation of CD4+ cells in normal individuals, while a different feature was observed when patients' cells were investigated. Cells from patients with L. aethiopica infection did not show this NK response, but rather the CD4+ cells were the prominent responding cells. No evidence of the involvement of superantigens or cells utilizing the gamma delta T cell receptor (gamma delta cells) in the response of unexposed individuals was noted.     

Activity of telithromycin and seven other agents against 1034 pediatric Streptococcus pneumoniae isolates from ten central and eastern European centers

Objective  To test the activity of telithromycin against 1034 Streptococcus pneumoniae isolates from pediatric patients in ten centers from ten central and eastern European countries during 2000–2001, and to compare it with the activities of erythromycin A, azithromycin, clarithromycin, clindamycin, and quinupristin–dalfopristin.
Methods  The minimum inhibitory concentrations (MICs) of telithromycin, erythromycin A, azithromycin, clarithromycin, clindamycin, levofloxacin, quinupristin–dalfopristin and penicillin G were tested by the agar dilution method with incubation in air, and mechanisms of resistance to macrolides and quinolones were investigated.
Results  Strains were isolated from sputum, tracheal aspirates, ear, eye, blood, and cerebrospinal fluid. Among S. pneumoniae strains tested, 36% had raised penicillin G MICs (≥ 0.12 mg/L). Susceptibilities were as follows: telithromycin, quinupristin–dalfopristin and levofloxacin, ≥ 99%; clindamycin, 83%; and erythromycin A, azithromycin and clarithromycin, 78%. Of 230 (22.3%) erythromycin A-resistant S. pneumoniae strains, 176 (79.6%) had erm(B) , 38 (16.1%) had mef(A) , and 10 (4.3%) had mutations in 23S ribosomal RNA or in ribosomal protein L4. The rates of drug-resistant S. pneumoniae are high in all centers except Kaunas, Riga, and Prague.
Conclusion  Telithromycin had low MICs against all strains, irrespective of macrolide, azalide or clindamycin resistance. Ribosomal methylation was the most prevalent resistance mechanism among all resistant strains, except in Sofia, where the prevalence of the efflux mechanism was higher.     

Seroprevalence of HPV vaccine types 6, 11, 16 and 18 in HIV-infected women from South Africa, Brazil and Botswana

Background

Many resource limited settings (RLS) suffer from high rates of both cervical cancer and HIV. Limited HPV serology data are available from RLS; such data could help describe local patterns of HPV infection and predict vaccine efficacy.

Objectives

To determine seropositivity to HPV types 6, 11, 16 and 18 in HIV-infected women from South Africa (SA), Botswana and Brazil.

Study design

HPV serotyping for high-risk types 6, 11, 16 and 18 was performed on samples collected from HIV-infected women from 2003–2010 using competitive Luminex Immuno Assay (HPV-4cLIA). We examined the association between seropositivity to these HPV types and country of enrollment, CD4, HIV-1 RNA level, and Pap smear.

Results

HPV serology results were available for 487 HIV-infected women (157, 170 and 160 from SA, Botswana and Brazil respectively). Approximately 65% of women had serum antibodies to one of the 4 HPV types and less than 3% of women had antibodies all 4 serotypes. Approximately 30% women demonstrated antibodies to type 16 HPV. Rates of seropositivity to HPV 11, and HPV 16+18 varied significantly between countries. Statistical difference was also shown in women in different age categories in the different countries. There was no difference in serology results compared by CD4 count, HIV viral load or Pap smear results.

Conclusions

These data suggest that the quadrivalent vaccine may be effective in preventing HPV infection in these countries.     

Seroprevalence of human herpesvirus-8 in blood donors from different geographical regions of Argentina, Brazil, and Chile

Human herpesvirus-8 (HHV-8) causes Kaposi's sarcoma (KS) and lymphoproliferative disorders in both HIV-infected and uninfected patients. HHV-8 has a worldwide occurrence but infection rates vary according to a combination of geographic and behavioral risks. The main transmission route seems to be sexual, nevertheless, nasal secretions, saliva, blood, and organ graft have been proposed. HHV-8 was postulated as a new infectious agent for screening in blood donors. The aim of this study was to evaluate the prevalence of antibodies against HHV-8 antigens in blood donors of South America. Serum samples from 2,470 blood donors from Argentina, Brazil, and Chile corresponding to five geographic regions were studied by indirect immunofluorescence assay (IFA). Seroprevalence rate was 3.7% (92/2,470; 95% CI 2.9-4.5) in the entire blood donor population distributed as follows: Argentina, 4.0% (Buenos Aires city, 4.3%; Bahia Blanca, 2.4%; and Córdoba, 4.0%), Campinas (Brazil), 2.8%; and Santiago de Chile, 3.0%. There was no difference (P>0.05) between men and women or age related, except in Brazil where positive cases were 30-49-year-old males. The present study, which includes different geographical areas of multiple countries from South America, has not been done before. The results show similar prevalence rates among the studied zones corresponding to low-prevalence regions. South America is a large sub-continent with a wide spectrum of population and geographical characteristics, thus, more HHV-8 prevalence studies should be necessary to establish possible regional differences.     

Multiple forms of chromosome I, II and V in a restricted population of Leishmania infantum contrasting with monomorphism in individual strains suggest haploidy or automixy.

We have resolved the molecular karyotypes of 22 Leishmania infantum strains isolated between 1980 and 1988 in a restricted geographic area and belonging to zymodemes MON-11, −29 and −33. Three strains were isolated from sandflies and all the others from human cutaneous lesions. A high degree of karyotypic homology is observed among these strains, contrasting with the highly polymorphic MON-1 strains isolated in the same area. We have analysed the time-dependent evolution of size variants of chromosomes I to V, each identified by chromosome-specific DNA probes. More evidence is given for the role of subtelomeric regions in chromosomal size variation in Leishmania for both chromosomes I and II. At the population level, the chromosomes I, II and V are present in respectively 8, 4 and 3 distinct sizes. Furthermore, and despite the small size of the sample, various combinations were observed among these different chromosomal forms. These results could be explained by the occurrence of a high rate of recurrent mutations or of genetic exchange. In contrast, only one chromosomal form was observed in individual karyotypes for the chromosomes I V. These results could tally with the hypothesis of a haploid organisation for these chromosomes and strains, or, in the frame of a diploid organisation, with the hypothesis of a predominantly automictic sexuality giving rise to 2 identical forms of the homologues in the same strain.