Dengue and climate changes: Increase of DENV-1 in São Paulo/Brazil - 2023.

Dengue is a vector borne disease caused by virus serotypes DENV-1, DENV-2, DENV-3, and DENV-4, representing a significant public health concern in the Region of the Americas (2,997,097 cases in 2023). This study explores the relationship between dengue incidence and climate changes in the city of São Paulo-Brazil. During the first semester of 2023, Brazil reported the highest number of dengue cases in Americas' Region. Our data reveals a correlation between the high temperature and rainfall season persistence and the extension of dengue incidence into the winter season. The findings highlight the importance of understanding the relationship between climate change and disease transmission patterns to develop effective strategies for prevention and control.

Isolated specific IgA against respiratory viruses, Influenza or SARS-CoV-2, present in the saliva of a fraction of healthy and asymptomatic volunteers.

OBJECTIVES: Defense against respiratory viruses depends on an immune response present in the mucosa, as saliva IgA secretes antibodies. During the pandemic, such as influenza or SARS-CoV-2, most infected patients are asymptomatic but retain specific antibodies post-infection. The authors evaluated IgG and IgA antibodies against SARS-CoV-2 and influenza in the saliva of asymptomatic volunteers, validated with controls or vaccinated individuals. METHODS: The authors detected specific antibodies by validated conventional ELISA using natural SARS-CoV-2 antigens from infected Vero cells or capture-ELISA for influenza using natural antigens of the influenza vaccine. RESULTS: Saliva from influenza-vaccinated individuals had more IgA than paired serum, contrary to the findings for specific IgG. In COVID-19-vaccinated samples, specific IgA in saliva increased after vaccination, but IgG levels were high after the first dose. In saliva from the asymptomatic population (226), anti-Influenza IgG was found in 57.5% (130) of samples, higher than IgA, found in 35% (79) of samples. IgA results were similar for SARS-CoV-2, with IgA present in 30% (68) of samples, while IgG was less present, in 44.2% (100) of samples. The proportion of influenza IgG responders was higher than that for SARS-CoV-2 IgG, but both populations presented similar proportions of IgA responders, possibly due to variable memory B cell survival. For both viruses, the authors found an important proportion (> 10%) of IgA+IgG- samples, suggesting the occurrence of humoral immunity directed to the mucosa. CONCLUSION: Specific antibodies for respiratory viruses in saliva are found in either infection or vaccination and are a convenient and sensitive diagnostic tool for host immune response.

Measles, rubella, mumps and Toxoplasma gondii antibodies in saliva of vaccinated students of schools and universities in São Paulo City, Brazil.

INTRODUCTION: Vaccines are well-established public health interventions with major impact on the prevalence of infectious diseases, but outbreaks are occurring frequently due to primary and secondary failures, despite high coverage. Surveillance of efficacy and duration of induced immunity is a difficult task as it requires invasive blood sampling in children and teenagers. Saliva can be an acceptable alternative source of IgG to assess vaccine efficacy and toxoplasmosis incidence. We investigated IgG response for measles, mumps, rubella, and T. gondii in saliva samples of vaccinated young people. METHODS: Saliva was collected from 249 public schools students from São Paulo, Brazil, aged 7 to 13 years old, during an interactive exhibition on hygiene. We used S. aureus protein A solid phase capture assay for IgG reactive to biotinylated purified proteins. Paired saliva and serum (47) were tested from young adults with serum evidence of T. gondii infection and from negative children less than 12 month old for standardization. Reproducibility was greater than 98% and sensitivity and specificity of the saliva assays were greater than 95%, as well as the concordance of paired saliva and serum samples. RESULTS: Saliva from high school students showed a prevalence of 8.5% (95% CI: 5.0-11.9%) for anti T. gondii IgG; 96.8% (94.6-99%) of anti-measles IgG; 59.1% (53-65%) of anti-rubella IgG, and 57.5% (51.3-63.6%) of anti-mumps IgG. DISCUSSION: The prevalence of antibodies against mumps and rubella after 6-8 years of vaccination was lower than against measles among students. The findings of this study demonstrate the feasibility of saliva sampling for follow-up of vaccine immune status in teenagers. This useful approach allows for IgG detection for vaccine control or epidemiological studies.

Saliva collection and detection of anti- T. gondii antibodies of low-income school-age children as a learning strategy on hygiene, prevention and transmission of toxoplasmosis.

School-age children are a social group in which blood collection for laboratory testing can be perceived as an invasive procedure, with low acceptance and tolerance of stakeholders. This problem could be circumvented by replacing serum samples with saliva. For this purpose, and to make the collection of saliva samples playful and instructive for children, educational activities on hygiene and toxoplasmosis transmission and prevention were performed using toys and audiovisual tools. The target audience consisted of 7-10 year-old children from low-income families who attended public schools in the city of São Paulo. Saliva samples were used in a previously described in-house Enzyme-Linked Immunosorbent Assays (ELISA) to detect anti- Toxoplasma gondii IgG antibodies and establish the immunological status of each of the participants. One year later, children's memory and fixation of concepts regarding hygiene habits, as well as transmission and prevention of toxoplasmosis were tested in the same schools, by means of a questionnaire application, using students who did not participate in the first intervention as controls. The prevalence of positive anti- T. gondii IgG among students was 50% (82/164). One year later, 45 children had more knowledge on toxoplasmosis (28/45 vs 29/147) and they drew the cat's involvement in the transmission of toxoplasmosis more often than controls (28/45 vs 29/147). Sorted according to the presence of specific IgG in saliva, recovered positive students presented worse memory of the above cited knowledge as did saliva-negative IgG students, but both groups had isolated higher frequency of fixed knowledge than non-intervened students. Our data show that there is a high prevalence of T. gondii infection in school-children from low-income areas; saliva is an alternative to blood for anti- T. gondii IgG detection; and a one-day educational intervention in school-children was effective in promoting knowledge fixation on hygiene and toxoplasmosis transmission and prevention after one year.

Vimentin and Anti Vimentin Antibodies in Chagas' Disease.

BACKGROUND: Vimentin is a main structural protein of the cell, a component of intermediate cell filaments and immersed in cytoplasm. Vimentin is mimicked by some bacterial proteins and anti-vimentin antibodies occur in autoimmune cardiac disease, as rheumatic fever. In this work we studied vimentin distribution on LLC-MK2 cells infected with T. cruzi and anti-vimentin antibodies in sera from several clinical pictures of Chagas' disease or American Trypanosomiasis, in order to elucidate any vimentin involvement in the humoral response of this pathology. OBJECTIVE: We standardized an indirect immunofluorescence assay (IFI) to determine sub cellular expression in either parasites and host cells, and ELISA to evaluate anti-vimentin antibodies in sera fron chagasic patients. METHODS: We analyzed the distribution of vimentin in culture cells using indirect fluorescent assays, using as external controls anti-T. cruzi sera, derived from chronic infected patients for identification of the parasites in the same model. After infection and growth of T.cruzi amastigotes, those cells express larger amounts of vimentin, with heavy staining of cytoplasm outside the parasitophorous vacuole and some particle shadowing patterns, suggesting that vimentin are associated with cell cytoplasm. Anti-vimentin antibodies were present in most American trypanosomiasis samples, but notably, they are much more present in acute (76, 9%) or clinical defined syndromes, especially cardiac disease (87, 9%). Paradoxically, they were relatively infrequent in asymptomatic (25%) infected patients, which had a clearly positive serological reaction to parasite antigens, but had low frequency of anti-vimentin antibodies, similar to controls (2,5%). CONCLUSION: Our current data revealed that anti-vimentin antibodies induced during T. cruzi infection could be a marker of active disease in the host and its levels could also justify drug therapy in American Trypanosomiasis chronic infection, as a large group of asymptomatic patients would be submitted to treatment with frequent adverse reactions of the available drugs. Anti-vimentin antibodies could be a marker of cardiac muscle cell damage, appearing in American Trypanosomiasis patients during active muscle cell damage.

Effect of chaotropes in Chagas disease and leishmaniasis cross-reacting serology assays for epidemiological surveys.

INTRODUCTION: Serological cross-reactivity between leishmaniasis and Chagas disease, especially at low titers, leads to difficulties of the seroepidemiological interpretation. METHODS: We have studied the ability of urea as a chaotrope to select high-avidity antibodies in IgG ELISA, thus reducing low-avidity IgG cross-reactivity in serologically positive samples in both assays. RESULTS: Using 0.5M urea for diluting the sample efficiently defined leishmaniasis or double infections in high-avidity IgG ELISA and eliminated false-positive results. CONCLUSIONS: The use of a chaotropic diluting agent is useful for improving the specificity of Chagas disease and leishmaniasis immunoassays.

Quality of life is severely compromised in adult patients with atopic dermatitis in Brazil, especially due to mental components.

PURPOSE: to measure the quality of life (QoL), either by a specific dermatology or generic self applied questionnaire, in Atopic dermatitis adult Brazilian patients, looking for selected affected groups. METHODS: We studied the quality of life of 75 Brazilian ambulatory adults with atopic dermatitis using two types of self-answered instruments: a quality of life generic questionnaire (SF-36) and a 10-item Dermatology Life Quality Index (DLQI) questionnaire. All patients had been treated for at least 6 months, and their disease status was determined by Eczema Area and Severity Index scores. RESULTS: Quality of life and disease control were found to be related but with low scores both in DLQI (r(2)=0.26) and in SF-36 (r(2)=0.20), but with greater correlation for SF-36 mental components. Using the 75% percentile distribution of SF36 mean score and the 75% value of disease severity score, we sorted patients into four groups: I, referring good QoL and mild atopic disease (14/75), II, referring bad QoL and with mild atopic disease (19/75), III referring good QoL despite severe atopic disease (5/75) and IV referring bad QoL and severe atopic disease (37/75); all groups presented similar age, education, family income and time of disease progression. There was a higher frequency of women in group II, but without sleep disturbance or increased pruritus, which was present in group IV, with intense itching and sleep disturbances. Analyzing the physical or mental components of the SF36 generic test, discrepant groups II and III presented higher differences related to the mental components of the test, which was also related to DLQI scores, with a similar distribution for the 2 groups and a higher relation to the mental component of the generic test. CONCLUSION: The quality of life is affected in adult atopic patients, both related to disease severity and also to mental components, but with diverse effects in patient subgroups. Our data show some components that may mask the exact relationship between QoL results and disease severity.

Isolated specific IgA against respiratory viruses, Influenza or SARS-CoV-2, present in the saliva of a fraction of healthy and asymptomatic volunteers

Abstract Objectives: Defense against respiratory viruses depends on an immune response present in the mucosa, as saliva IgA secretes antibodies. During the pandemic, such as influenza or SARS-CoV-2, most infected patients are asymptomatic but retain specific antibodies post-infection. The authors evaluated IgG and IgA antibodies against SARS-CoV-2 and influenza in the saliva of asymptomatic volunteers, validated with controls or vaccinated individuals. Methods: The authors detected specific antibodies by validated conventional ELISA using natural SARS-CoV-2 antigens from infected Vero cells or capture-ELISA for influenza using natural antigens of the influenza vaccine. Results: Saliva from influenza-vaccinated individuals had more IgA than paired serum, contrary to the findings for specific IgG. In COVID-19-vaccinated samples, specific IgA in saliva increased after vaccination, but IgG levels were high after the first dose. In saliva from the asymptomatic population (226), anti-Influenza IgG was found in 57.5% (130) of samples, higher than IgA, found in 35% (79) of samples. IgA results were similar for SARS-CoV-2, with IgA present in 30% (68) of samples, while IgG was less present, in 44.2% (100) of samples. The proportion of influenza IgG responders was higher than that for SARS-CoV-2 IgG, but both populations presented similar proportions of IgA responders, possibly due to variable memory B cell survival. For both viruses, the authors found an important proportion (> 10%) of IgA+IgG- samples, suggesting the occurrence of humoral immunity directed to the mucosa. Conclusion: Specific antibodies for respiratory viruses in saliva are found in either infection or vaccination and are a convenient and sensitive diagnostic tool for host immune response.

Antimonial drugs entrapped into phosphatidylserine liposomes: physicochemical evaluation and antileishmanial activity.

INTRODUCTION: Leishmaniasis is a disease caused by the protozoan Leishmania that resides mainly in mononuclear phagocytic system tissues. Pentavalent antimonials are the main treatment option, although these drugs have toxic side effects and high resistance rates. A potentially alternative and more effective therapeutic strategy is to use liposomes as carriers of the antileishmanial agents. The aims of this study were to develop antimonial drugs entrapped into phosphatidylserine liposomes and to analyze their biological and physicochemical characteristics. METHODS: Liposomes containing meglumine antimoniate (MA) or pentavalent antimony salt (Sb) were obtained through filter extrusion (FEL) and characterized by transmission electron microscopy. Promastigotes of Leishmania infantum were incubated with the drugs and the viability was determined with a tetrazolium dye (MTT assay). The effects of these drugs against intracellular amastigotes were also evaluated by optical microscopy, and mammalian cytotoxicity was determined by an MTT assay. RESULTS: Liposomes had an average diameter of 162nm. MA-FEL showed inhibitory activity against intracellular L. infantum amastigotes, with a 50% inhibitory concentration (IC50) of 0.9µg/mL, whereas that of MA was 60µg/mL. Sb-FEL showed an IC50 value of 0.2µg/mL, whereas that of free Sb was 9µg/mL. MA-FEL and Sb-FEL had strong in vitro activity that was 63-fold and 39-fold more effective than their respective free drugs. MA-FEL tested at a ten-times higher concentration than Sb-FEL did not show cytotoxicity to mammalian cells, resulting in a higher selectivity index. CONCLUSIONS: Antimonial drug-containing liposomes are more effective against Leishmania-infected macrophages than the non-liposomal drugs.

CD19 LYMPHOCYTE PROLIFERATION INDUCED BY Bifidobacterium animalis subsp. lactis IN C57BL/6 MICE EXPERIMENTALLY INFECTED WITH Toxoplasma gondii.

Toxoplasmosis is frequently acquired through the oral route by the ingestion of cysts or oocysts of Toxoplasma gondii. Once ingested, the parasites penetrate the intestinal epithelial cells and rapidly disseminate to all organs in the host. During T. gondii infection, the intestinal microbiota plays an important role in stimulating a protective immune response against the parasite. In this sense the use of probiotics is worthy of note since they are live microorganisms that have beneficial effects on the host through stimulation of the immune response that can be important in the control of T. gondii proliferation and dissemination in the host. In the present study, the action of the probiotic Bifidobacterium animalis subsp. lactis was investigated in C57BL/6 mice infected with oocysts of ME49 strain of T. gondii. The probiotic had an immunomodulatory action, inducing CD19 lymphocyte proliferation and consequently increasing anti-T. gondii antibody level. Bifidobacterium animalis subsp. lactis provided protection in supplemented mice, compared to the control group. In addition, supplemented animals had milder inflammatory process in the small intestine, indicating that the probiotic protects the intestinal mucosa during infection with T. gondii. It was concluded that the probiotic B. animalis subsp. lactis induces humoral immune response capable of providing protection against T. gondii infection.

Measles, rubella, mumps and Toxoplasma gondii antibodies in saliva of vaccinated students of schools and universities in São Paulo City, Brazil

ABSTRACT Introduction: Vaccines are well-established public health interventions with major impacton the prevalence of infectious diseases, but outbreaks are occurring frequently due to pri-mary and secondary failures, despite high coverage. Surveillance of efficacy and duration ofinduced immunity is a difficult task as it requires invasive blood sampling in children andteenagers. Saliva can be an acceptable alternative source of IgG to assess vaccine efficacyand toxoplasmosis incidence. We investigated IgG response for measles, mumps, rubella,and T. gondii in saliva samples of vaccinated young people. Methods: Saliva was collected from 249 public schools students from São Paulo, Brazil, aged7 to 13 years old, during an interactive exhibition on hygiene. We used S. aureus proteinA solid phase capture assay for IgG reactive to biotinylated purified proteins. Paired salivaand serum (47) were tested from young adults with serum evidence of T. gondii infectionand from negative children less than 12 month old for standardization. Reproducibility wasgreater than 98% and sensitivity and specificity of the saliva assays were greater than 95%,as well as the concordance of paired saliva and serum samples. Results: Saliva from high school students showed a prevalence of 8.5% (95% CI: 5.0-11.9%)for anti T. gondii IgG; 96.8% (94.6-99%) of anti-measles IgG; 59.1% (53-65%) of anti-rubella IgG,and 57.5% (51.3-63.6%) of anti-mumps IgG. Discussion: The prevalence of antibodies against mumps and rubella after 6-8 years of vaccination was lower than against measles among students. The findings of this study demonstrate the feasibility of saliva sampling for follow-up of vaccine immune status in teenagers. This useful approach allows for IgG detection for vaccine control or epidemio- logical studies.

Avaliação das reações de Hemaglutinação Indireta (HI) e Aglutinação Modificada (MAT) na detecção de anticorpos IgG anti-T. gondii em exsudatos cárneos bovinos / Evaluation of indirect Hemagglutination (HI) and Modified Agglutination (MAT) reactions in the detection of anti-T. gondiiIgG antibodies in bovine meat exudates

Toxoplasmose é uma zoonose parasitária com ampla distribuição mundial provocada pelo Toxoplasma gondii, considerado um dos protozoários mais bem sucedidos do planeta, pois infecta cerca de um terço da população mundial. Dentre as formas de transmissão, o consumo de carne mal cozida, contendo cistos, tem sido considerado um fator de risco para aquisição desta zoonose. Uma abordagem alternativa para o controle da toxoplasmose pela ingestão de carne bovina seria a sorologia dos bovinos, já que animais soropositivos albergam cistos teciduais. Contudo, a obtenção de soro para esta avaliação, nem sempre é factível, dada a dificuldade de coleta de sangue durante a linha de abate e sua ausência em cortes comerciais. O exsudato cárneo é uma alternativa para detecção de anticorpos anti - T. gondii em cortes comerciais de carne, que foi a proposta deste estudo para avaliar o desempenho dos testes de Hemaglutinação Indireta (HI) e Aglutinação Modificada (MAT) quando comparados ao ELISA usando exsudato cárneo. Este estudo mostrou que a acurácia dos testes de aglutinação não foi viável devido aos baixos índices de sensibilidade e especificidade quando comparados ao ELISA. Estes dados demonstram a importância da escolha de testes eficientes como ELISA para aplicação no controle da qualidade e inocuidade de cortes comerciais de carne bovina. (AU)

Toxoplasmosis is a parasitic zoonosis with a wide worldwide distribution caused by Toxoplasmagondii, which is considered one of the most successful protozoa on the planet, since it can infect a third of the world population. Among the forms of transmission, consumption of undercooked meat has been considered as a risk factor for the acquisition of this zoonosis. An alternative approach to toxoplasmosis control by beef ingestion could be the serological diagnosis in cattle, since seropositives animals harbor tissue cysts. However, the use of serum for this evaluation is not always feasible due to the difficulty of blood collection during slaughter and its absence in commercial beef cuts. Meat exudate is an alternative for the detection of anti-T. gondii antibodies in commercial beef cuts, which was the propose of this study to evaluate the performance of Indirect Hemagglutination (HI) and Agglutination Modified (MAT) tests compared to ELISA using meat exudates. This study showed that the agglutination tests accuracy was not viable due to low sensitivity and specificity indexes when compared to ELISA. These data demonstrate the importance of choosing accurate tests such as ELISA for application in quality control and safety of commercial beef cuts. (AU)

Avaliação das reações de Hemaglutinação Indireta (HI) e Aglutinação Modificada (MAT) na detecção de anticorpos IgG anti-T. gondii em exsudatos cárneos bovinos / Evaluation of indirect Hemagglutination (HI) and Modified Agglutination (MAT) reactions in the detection of anti-T. gondii IgG antibodies in bovine meat exudates

Toxoplasmose é uma zoonose parasitária com ampla distribuição mundial provocada pelo Toxoplasma gondii, considerado um dos protozoários mais bem sucedidos do planeta, pois infecta cerca de um terço da população mundial. Dentre as formas de transmissão, o consumo de carne mal cozida, contendo cistos, tem sido considerado um fator de risco para aquisição desta zoonose. Uma abordagem alternativa para o controle da toxoplasmose pela ingestão de carne bovina seria a sorologia dos bovinos, já que animais soropositivos albergam cistos teciduais. Contudo, a obtenção de soro para esta avaliação, nem sempre é factível, dada a dificuldade de coleta de sangue durante a linha de abate e sua ausência em cortes comerciais. O exsudato cárneo é uma alternativa para detecção de anticorpos anti - T. gondii em cortes comerciais de carne, que foi a proposta deste estudo para avaliar o desempenho dos testes de Hemaglutinação Indireta (HI) e Aglutinação Modificada (MAT) quando comparados ao ELISA usando exsudato cárneo. Este estudo mostrou que a acurácia dos testes de aglutinação não foi viável devido aos baixos índices de sensibilidade e especificidade quando comparados ao ELISA. Estes dados demonstram a importância da escolha de testes eficientes como ELISA para aplicação no controle da qualidade e inocuidade de cortes comerciais de carne bovina.

Toxoplasmosis is a parasitic zoonosis with a wide worldwide distribution caused by Toxoplasma gondii, which is considered one of the most successful protozoa on the planet, since it can infect a third of the world population. Among the forms of transmission, consumption of undercooked meat has been considered as a risk factor for the acquisition of this zoonosis. An alternative approach to toxoplasmosis control by beef ingestion could be the serological diagnosis in cattle, since seropositives animals harbor tissue cysts. However, the use of serum for this evaluation is not always feasible due to the difficulty of blood collection during slaughter and its absence in commercial beef cuts. Meat exudate is an alternative for the detection of anti-T. gondii antibodies in commercial beef cuts, which was the propose of this study to evaluate the performance of Indirect Hemagglutination (HI) and Agglutination Modified (MAT) tests compared to ELISA using meat exudates. This study showed that the agglutination tests accuracy was not viable due to low sensitivity and specificity indexes when compared to ELISA. These data demonstrate the importance of choosing accurate tests such as ELISA for application in quality control and safety of commercial beef cuts.

Pharmacokinetics of neutron-irradiated meglumine antimoniate in Leishmania amazonensis-infected BALB/c mice

Cutaneous leishmaniasis (CL) is a parasitic disease caused by the protozoan Leishmania spp. Pentavalent antimonial agents have been used as an effective therapy, despite their side effects and resistant cases. Their pharmacokinetics remain largely unexplored. This study aimed to investigate the pharmacokinetic profile of meglumine antimoniate in a murine model of cutaneous leishmaniasis using a radiotracer approach. Methods: Meglumine antimoniate was neutron-irradiated inside a nuclear reactor and was administered once intraperitoneally to uninfected and L. amazonensis-infected BALB/c mice. Different organs and tissues were collected and the total antimony was measured. Results: Higher antimony levels were found in infected than uninfected footpad (0.29% IA vs. 0.14% IA, p = 0.0057) and maintained the concentration. The animals accumulated and retained antimony in the liver, which cleared slowly. The kidney and intestinal uptake data support the hypothesis that antimony has two elimination pathways, first through renal excretion, followed by biliary excretion. Both processes demonstrated a biphasic elimination profile classified as fast and slow. In the blood, antimony followed a biexponential open model. Infected mice showed a lower maximum concentration (6.2% IA/mL vs. 11.8% IA/mL, p = 0.0001), a 2.5-fold smaller area under the curve, a 2.7-fold reduction in the mean residence time, and a 2.5-fold higher clearance rate when compared to the uninfected mice. Conclusions: neutron-irradiated meglumine antimoniate concentrates in infected footpad, while the infection affects antimony pharmacokinetics.(AU)

Uneventful benznidazole treatment of acute Chagas disease during pregnancy: a case report.

This report describes the case of a patient with acute Chagas disease in Tocantins, Brazil, who was unaware of her pregnancy during benznidazole treatment. She presented with impaired cardiac function during the acute phase (pericarditis and incomplete right bundle-branch block) that resolved favorably after benznidazole therapy. Serological results also became negative, as determined by hemagglutination assays, enzyme-linked immunosorbent assays, and immunofluorescence assays. The child was born without sequelae and showed no evidence of congenital Trypanosoma cruzi infection at birth or 24 days later.

Health problems awareness during travel among faculty members of a large university in Latin America: preliminary report.

Health safety during trips is based on previous counseling, vaccination and prevention of infections, previous diseases or specific problems related to the destination. Our aim was to assess two aspects, incidence of health problems related to travel and the traveler's awareness of health safety. To this end we phone-interviewed faculty members of a large public University, randomly selected from humanities, engineering and health schools. Out of 520 attempts, we were able to contact 67 (12.9%) and 46 (68.6%) agreed to participate in the study. There was a large male proportion (37/44, 84.1%), mature adults mostly in their forties and fifties (32/44, 72.7%), all of them with higher education, as you would expect of faculty members. Most described themselves as being sedentary or as taking occasional exercise, with only 15.9% (7/44) taking regular exercise. Preexisting diseases were reported by 15 travelers. Most trips lasted usually one week or less. Duration of the travel was related to the destination, with (12h) or longer trips being taken by 68.2% (30/44) of travelers, and the others taking shorter (3h) domestic trips. Most travelling was made by air (41/44) and only 31.8% (14/44) of the trips were motivated by leisure. Field research trips were not reported. Specific health counseling previous to travel was reported only by two (4.5%). Twenty seven of them (61.4%) reported updated immunization, but 11/30 reported unchecked immunizations. 30% (9/30) reported travel without any health insurance coverage. As a whole group, 6 (13.6%) travelers reported at least one health problem attributed to the trip. All of them were males travelling abroad. Five presented respiratory infections, such as influenza and common cold, one neurological, one orthopedic, one social and one hypertension. There were no gender differences regarding age groups, destination, type of transport, previous health counseling, leisure travel motivation or pre-existing diseases. Interestingly, the two cases of previous health counseling were made by domestic travelers. Our data clearly shows that despite a significant number of travel related health problems, these highly educated faculty members, had a low awareness of those risks, and a significant number of travels are made without prior counseling or health insurance. A counseling program conducted by a tourism and health professional must be implemented for faculty members in order to increase the awareness of travel related health problems.

Vimentin and Anti Vimentin Antibodies in Chagas' Disease / Vimentina e Anticorpos Anti-Vimentina na Doença de Chagas

Abstract Background: Vimentin is a main structural protein of the cell, a component of intermediate cell filaments and immersed in cytoplasm. Vimentin is mimicked by some bacterial proteins and anti-vimentin antibodies occur in autoimmune cardiac disease, as rheumatic fever. In this work we studied vimentin distribution on LLC-MK2 cells infected with T. cruzi and anti-vimentin antibodies in sera from several clinical pictures of Chagas' disease or American Trypanosomiasis, in order to elucidate any vimentin involvement in the humoral response of this pathology. Objective: We standardized an indirect immunofluorescence assay (IFI) to determine sub cellular expression in either parasites and host cells, and ELISA to evaluate anti-vimentin antibodies in sera fron chagasic patients. Methods: We analyzed the distribution of vimentin in culture cells using indirect fluorescent assays, using as external controls anti-T. cruzi sera, derived from chronic infected patients for identification of the parasites in the same model. After infection and growth of T.cruzi amastigotes, those cells express larger amounts of vimentin, with heavy staining of cytoplasm outside the parasitophorous vacuole and some particle shadowing patterns, suggesting that vimentin are associated with cell cytoplasm. Anti-vimentin antibodies were present in most American trypanosomiasis samples, but notably, they are much more present in acute (76, 9%) or clinical defined syndromes, especially cardiac disease (87, 9%). Paradoxically, they were relatively infrequent in asymptomatic (25%) infected patients, which had a clearly positive serological reaction to parasite antigens, but had low frequency of anti-vimentin antibodies, similar to controls (2,5%). Conclusion: Our current data revealed that anti-vimentin antibodies induced during T. cruzi infection could be a marker of active disease in the host and its levels could also justify drug therapy in American Trypanosomiasis chronic infection, as a large group of asymptomatic patients would be submitted to treatment with frequent adverse reactions of the available drugs. Anti-vimentin antibodies could be a marker of cardiac muscle cell damage, appearing in American Trypanosomiasis patients during active muscle cell damage.

Resumo Fundamento: A Vimentina é uma proteína estrutural importante da célula, um componente dos filamentos celulares intermediários e imersa no citoplasma. Algumas proteínas bacterianas imitam a Vimentina e anticorpos anti-vimentina ocorrem em doenças cardíacas auto-imunes, como a febre reumática. Neste trabalho, estudamos a distribuição de vimentina em células LLC-MK2 infectadas com T. Cruzi e anticorpos anti-vimentina em soros de várias imagens clínicas da doença de Chagas ou tripanossomíases americanas, a fim de elucidar qualquer implicação da vimentina na resposta humoral desta patologia. Objetivo: padronizamos um teste de imunofluorescência indireta (IFI) para determinar a expressão subcelular em parasitas e células hospedeiras, e ELISA para testar anticorpos anti-vimentina em soros de pacientes chagásicos. Métodos: analisamos a distribuição de vimentina em células de cultura usando ensaios fluorescentes indiretos, utilizando como controles externos soros anti-T. Cruzi, derivados de pacientes com infecção crônica para a identificação de parasitas no mesmo modelo. Após a infecção e o crescimento de amastigotas de T. Cruzi, essas células expressam grandes quantidades de vimentina, com forte coloração do citoplasma fora da vacuola parasitófora e alguns padrões de sombreamento das partículas, sugerindo que a vimentina está associada ao citoplasma da célula. Os anticorpos anti-vimentina estavam presentes na maioria das amostras americanas de tripanossomíases, mas estão notavelmente mais presentes em síndromes agudas ou clinicamente definidas (76,9%), especialmente em doenças cardíacas (87,9%). Paradoxalmente, eram relativamente infrequentes em pacientes infectados assintomáticos (25%), que apresentavam uma reação sorológica claramente positiva aos antígenos parasitas, mas apresentavam baixa frequência de anticorpos anti-vimentina, semelhante aos controles (2,5%). Conclusão: Nossos dados atuais revelaram que os anticorpos anti-vimentina induzidos durante a infecção por T. Cruzi poderiam ser um marcador de doença ativa no hospedeiro e seus níveis também poderiam justificar o tratamento farmacológico em infecção crônica com tripanossomíase americana, uma vez que um grande grupo de pacientes assintomáticos seria submetido a tratamento com reações adversas frequentes aos medicamentos disponíveis. Os anticorpos anti-vimentina poderiam ser um marcador de danos nas células do músculo cardíaco, que aparece em pacientes com tripanossomíase americana durante o dano das células musculares ativas.

Effect of chaotropes in Chagas disease and leishmaniasis cross-reacting serology assays for epidemiological surveys

Abstract INTRODUCTION: Serological cross-reactivity between leishmaniasis and Chagas disease, especially at low titers, leads to difficulties of the seroepidemiological interpretation. METHODS: We have studied the ability of urea as a chaotrope to select high-avidity antibodies in IgG ELISA, thus reducing low-avidity IgG cross-reactivity in serologically positive samples in both assays. RESULTS: Using 0.5M urea for diluting the sample efficiently defined leishmaniasis or double infections in high-avidity IgG ELISA and eliminated false-positive results. CONCLUSIONS: The use of a chaotropic diluting agent is useful for improving the specificity of Chagas disease and leishmaniasis immunoassays.

Case-control study of an outbreak of acute toxoplasmosis in an industrial plant in the state of São Paulo, Brazil.

Foodborne diseases represent operational risks in industrial restaurants. We described an outbreak of nine clustered cases of acute illness resembling acute toxoplasmosis in an industrial plant with 2300 employees. These patients and another 36 similar asymptomatic employees were diagnosed with anti-T. gondii IgG titer and avidity by ELISA. We excluded 14 patients based on high IgG avidity and chronic toxoplasmosis: 13 from controls and one from acute disease other than T. gondii infection. We also identified another three asymptomatic employees with T.gondii acute infection and also anti-T. gondii IgM positive as remaining acute cases. Case control study was conducted by interview in 11 acute infections and 20 negative controls. The ingestion of green vegetables, but not meat or water, was observed to be associated with the incidence of acute disease. These data reinforce the importance of sanitation control in industrial restaurants and also demonstrate the need for improvement in quality control regarding vegetables at risk for T. gondii oocyst contamination. We emphasized the accurate diagnosis of indexed cases and the detection of asymptomatic infections to determine the extent of the toxoplasmosis outbreak.