No seroconversion among healthcare workers exposed to SARS-CoV-2 during the early phase of the pandemic / Ausencia de seroconversión en trabajadores de la salud expuestos a SARS-CoV-2 durante la primera fase de la pandemia

BACKGROUND: The SARS-CoV-2 pandemic is associated with morbidity, hospitalizations, absenteeism, and mortality among healthcare workers (HCW). AIM: To evaluate the seroconversion rate in HCW exposed to SARS-CoV-2 in the early pandemic phase in 2020 at a regional reference hospital. MATERIAL AND METHODS: One hundred seventy-nine HCW working at a regional hospital were invited to a longitudinal study performed between April-July 2020. A serological analysis by ELISA IgG for viral nucleoprotein and protein S with a secondary analysis by ELISA IgG protein S1/S2 for samples with positive or doubtful result was carried out together with a complementary online survey to inquire about occupational or community exposures to SARS-CoV-2. RESULTS: Two cases with baseline infection were detected (1.1%, one symptomatic and one asymptomatic) and no cases of seroconversion were detected. During the study period, there were 136 patients hospitalized with COVID-19, and regional weekly COVID-19 incidence ranged from 2.7 to 24.4 per 100,000 inhabitants. No SARS-CoV-2 cases were detected by PCR among 27 HCW who consulted for respiratory symptoms in the period. Online surveys confirmed direct care of COVID-19 patients and also detected a high degree of unprotected social interaction at work. CONCLUSIONS: There was no evidence of seroconversion in this group of HCW exposed to the risk of infection by SARS-CoV-2 during the onset of the COVID-19 pandemic. Personal protective equipment and other measures used by the HCW were extremely useful for their protection in the initial phase of the pandemic.

ANTECEDENTES: La pandemia de SARS-CoV-2 está asociada a morbilidad, hospitalizaciones, ausentismo y mortalidad entre el personal de salud (PS). OBJETIVO: Evaluar la tasa de seroconversión en el PS expuesto al SARS-CoV-2 en la fase pandémica inicial el 2020 en un hospital regional de referencia. MATERIAL Y MÉTODOS: Ciento setenta y nueve trabajadores de la salud fueron invitados a un estudio longitudinal realizado entre abril-julio de 2020. Se efectuó un análisis serológico por ELISA IgG para nucleoproteína viral y proteína S con un análisis secundario por ELISA IgG proteína S1 / S2 para muestras con resultado positivo o dudoso junto a encuestas complementarias en línea para preguntar sobre exposiciones ocupacionales o comunitarias al SARS-CoV-2. RESULTADOS: Se detectaron dos casos con infección basal (1,1%, uno sintomático y uno asintomático) sin casos de seroconversión. Durante el período de estudio, hubo 136 pacientes hospitalizados con COVID-19, y la incidencia semanal regional de COVID-19 osciló entre 2,7 y 24,4 por 100.000 habitantes. No se detectaron casos de SARS-CoV-2 por PCR entre los 27 funcionarios que consultaron por síntomas respiratorios en este período. Las encuestas en línea confirmaron la atención directa de los pacientes con COVID-19 y también detectaron un alto grado de interacción social desprotegida en el trabajo. CONCLUSIONES: No hubo evidencia de seroconversión en un grupo de funcionarios expuestos al riesgo de infección por SARS-CoV-2 durante el inicio de la pandemia de COVID-19. Los equipos de protección personal y otras medidas utilizadas por el PS fueron de suma utilidad para su protección en la fase inicial de la pandemia.

Centenaria institucionalizada recuperada por COVID-19 con generación de inmunidad: Un caso de estudio / A centenarian institutionalized patient who recovered from COVID-19 and developed immunity: A case study

Resumen Introducción: El virus SARS-CoV-2 y su enfermedad COVID-19, afecta con mayor severidad a personas adultas mayores, sobre todo aquellas con multimorbilidad y fragilidad; esto debido a mecanismos fisiológicos como la inmunosenescencia o un pobre control de la actividad inflamatoria en esta población. Los estudios sobre el diagnóstico y tratamiento en estos pacientes son escasos y muchos de ellos tienen niveles de evidencia bajos. Objetivo: Describir las características clínicas y paraclínicas de una adulta mayor centenaria institucionalizada, frágil, con multimorbilidad quien sobrevive a la infección y desarrolla inmunidad en una unidad geriátrica de agudos. Presentación del caso: Centenaria institucionalizada con multimorbilidad y fragilidad con criterios de severidad de la enfermedad, quien fue manejada tempranamente y recuperada, llegando a desarrollar inmunidad. Conclusiones: El diagnóstico temprano, un manejo precoz y el abordaje geriátrico integral e interdisciplinar son indispensables para un desenlace favorable en pacientes adultos mayores con alto riesgo de progresión de enfermedad con COVID-19.

Abstract Introduction: SARS-CoV-2 virus, and the disease it causes (COVID-19), severely affects older adults (OA), especially those with multimorbidity and frailty. This is due to physiological mechanisms such as immunosenescence or poor control of inflammatory activity in this population. Studies of the diagnoses and treatments in these patients are scarce and many of them have low levels of evidence. Objective: To describe the clinical and paraclinical characteristics of a frail institutionalized centenarian female patient with multimorbidity who survived COVID-19 infection, developed immunity, and was treated in an acute geriatric unit. Case presentation: Institutionalized centenarian patient with multimorbidity and frailty who fulfilled the criteria for severe COVID-19 disease, was managed early, recovered, and eventually developed immunity. Conclusion: early diagnosis, early management and a comprehensive and interdisciplinary geriatric approach are essential for a favorable outcome in OA patients at high risk of COVID-19 disease progression.

Seroprevalence and seroconversion rates to SARS-CoV-2 in interns, residents, and medical doctors in a University Hospital in Bogotá, Colombia / Tasas de seroprevalencia y seroconversión al SARS-CoV-2 en internos, residentes y médicos en un Hospital Universitario de Bogotá, Colombia

Abstract Objectives: To determine the prevalence of antibodies to SARS-CoV-2 and the incidence of seroconversion in the first month of follow-up among interns, residents, and medical doctors attending patients at a University Hospital in Bogota (Colombia). Design or methods: A cross-sectional and a prospective study were performed during June, July, and August 2020 to assess seroprevalence and seroconversion rates using CLIA IgG for SARS-CoV-2. LFA IgG and IgM and ELFA IgM were also determined to explore concordance with CLIA IgG. Results: At baseline, 8 (2.28% 95%CI 1.16-4.43%) participants were IgG positive for SARS-CoV-2 by CLIA. At the end of the study, 21 (5.98% 95%CI 3.94-8.97%) individuals seroconverted by CLIA IgG. In all, 29 individuals had IgG by CLIA and of these 11 (3.13% 95%CI 1.76-5.52%) were asymptomatic. No associations with risk factors for infection were identified. CLIA IgG had moderate concordance (>962 samples) with LFA IgG and ELFA IgM, but minimal with LFA IgM. Conclusions: Our report is the first in Latina America on seroprevalence and seroconversion rates in medical healthcare workers. The relatively high rate (>3%) of asymptomatic health care workers with evidence of previous SARS-CoV-2 infection underscores the need to screen this population for infection to prevent infection/disease spread.

Resumen Objetivos: Determinar la prevalencia de anticuerpos frente al SARS-CoV-2 y la incidencia de seroconversión en el primer mes de seguimiento en internos, residentes y médicos que atienden pacientes en un Hospital Universitario de Bogotá (Colombia). Diseño y métodos: Se realizó un estudio transversal y prospectivo durante junio, julio y agosto de 2020 para evaluar las tasas de seroprevalencia y seroconversión utilizando CLIA IgG para SARS-CoV-2. También se determinaron LFA IgG e IgM y ELFA IgM para explorar la concordancia con CLIA IgG. Resultados: Al inicio del estudio, 8 (2,28% IC del 95% 1,16-4,43%) participantes fueron IgG positivos para SARS-CoV-2 por CLIA. Al final del estudio, 21 (5,98% IC 95% 3,94-8,97%) individuos seroconvirtieron por CLIA IgG. En total, 29 individuos tenían IgG por CLIA y de estos 11 (3,13% 95% IC 1,76-5,52%) eran asintomáticos. No se identificaron asociaciones con factores de riesgo de infección. El CLIA IgG tuvo una concordancia moderada (> 962 muestras) con LFA IgG y ELFA IgM, pero mínima con el LFA IgM. Conclusiones: Nuestro informe es el primero en América Latina sobre tasas de seroprevalencia y seroconversión en trabajadores médicos de la salud. La tasa relativamente alta (> 3%) de trabajadores de la salud asintomáticos con evidencia de infección previa por SARS-CoV-2 resalta la necesidad de realizar pruebas de detección de infección en esta población para prevenir la propagación de la infección.

Presentaciones inesperadas de enfermedades endémicas: síndrome de dificultad respiratoria aguda en un paciente con dengue / Unexpected presentations of endemic conditions: acute respiratory distress syndrome in a dengue patient

El dengue es la infección trasmitida por vectores con mayor impacto en carga de enfermedad, económica y social a nivel mundial, con más de 3,6 billones de personas en riesgo de infección. Sus manifestaciones son variables, caracterizadas en su mayoría por síndrome febril con riesgo de sangrado, choque y muerte. El compromiso pulmonar es infrecuente, siendo el síndrome de dificultad respiratoria aguda una complicación inesperada, aunque informada, asociada a un mal pronóstico. Se presenta un paciente sin antecedentes relevantes de importancia, con focalización pulmonar severa asociado a infección por el virus dengue. En el caso presentado se descartaron procesos infecciosos bacterianos u otros agentes causales de síndrome de dificultad respiratoria aguda, lo que sumado a las características clínicas de ingreso, zona de ocurrencia del caso considerada como endémica, curso clínico, paraclínico y la franca positividad de las pruebas para dengue así como la seroconversión de estas, a pesar de no haber sido realizadas pruebas moleculares, se consideró como el agente causal más probable el virus dengue. Todo esto lleva a recomendar siempre considerarlo como potencial agente causal, lo que permite así un diagnóstico y manejo óptimos(AU)

Dengue is the vector-borne infection with the greatest impact on disease, economic and social burden worldwide, with more than 3.6 billion people under risk of contagion. Its manifestations are varied, most of them characterized by febrile syndrome with a risk of bleeding, shock and death. Pulmonary involvement is infrequent, and acute respiratory distress syndrome is an unexpected complication, though it has been reported in association to a bad prognosis. A case is presented of a male patient without relevant antecedents of interest, with severe pulmonary focalization associated to dengue virus infection. Bacterial infectious processes and other causative agents of acute respiratory distress syndrome were ruled out. In view of the patient's clinical status at admission, the endemicity of the patient's area of residence, the clinical and paraclinical course, and the obvious positivity of the dengue tests performed and their seroconversion, despite not having conducted molecular tests, it was concluded that the most probable causative agent was dengue virus. Therefore, it is recommended that dengue infection always be considered as a potential causative agent of acute respiratory distress syndrome, thus contributing to optimal diagnosis and management(AU)

Self-prescribed Ivermectin use is associated with a lower rate of seroconversion in health care workers diagnosed with COVID, in a dose-dependent response

ABSTRACT Background: Over-the-counter use of ivermectin amongst other drugs as SARS-CoV-2 treatment has been increasingly common, despite the lack of evidence on its clinical efficacy. Objective: To evaluate the effect of ivermectin use on production of antibodies against SARS-CoV-2 in health care workers (HCW) diagnosed with COVID-19 and of Th1/Th2 cytokines by stimulated peripheral blood mononuclear cells of the same cohort (PBMCs). Methods: This cross-sectional study evaluated seroconversion and neutralizing antibodies production in HCW at Complexo Hospitalar Universitário Professor Edgard Santos (Salvador, Brazil), diagnosed with COVID-19 from May to July, 2020, as well as in vitro production of antibody against SARS-CoV-2 and Th1/Th2 cytokines. Analyses were performed between December 2020 and February 2021. Participants were stratified according to the use of ivermectin (≤ 1 dose vs. multiple doses) for treatment of COVID-19. Results: 45 HCW were included (62% women). Mean age was 39 years, and disease severity was similar across groups. Neutralizing antibodies were detected less frequently in multiple doses (70%) vs. ≤ 1 dose (97%) groups, p = 0.02). PBMCs of patients in multiple doses group also were less likely to produce antibodies against SARS-CoV-2 following in vitro stimulation with purified spike protein in comparison with patients in ≤ 1 dose group (p < 0.001). PBMC's production of Th1/Th2 cytokines levels was similar across groups. Abdominal pain (15% vs 46%, p = 0.04), diarrhea (21% vs. 55%, p = 0.05) and taste perversion (0% vs. 18%, p = 0.05) were more frequently reported by participants that used multiple doses of ivermectin. Conclusions: Although there was no evidence for differential disease severity upon ivermectin use for treatment of COVID-19 it was associated with more gastro-intestinal side-effects and impairment of anti-SARS-CoV2 antibodies production, in a dose dependent manner. This potentially impacts the effectiveness of immune response and the risk of reinfection and warrants additional studies for clarifying the mechanisms and consequences of such immunomodulatory effects.

Análise da soroconversão após esquema habitual de vacinação contra hepatite B em pacientes com doenças inflamatórias intestinais / Seroconversion analysis after habitual hepatitis b vaccination scheme in patients with inflammatory bowel diseases

ABSTRACT BACKGROUND: Patients with inflammatory bowel disease (IBD) vaccinated for hepatitis B have a low success rate in achieving protective antibody levels. The main factors suggested for this are IBD itself and the use of immunosuppressive drugs. OBJECTIVE: To evaluate the concentration of anti-HBs antibodies and to verify factors associated with the effectiveness of hepatitis B vaccination in patients with IBD. METHODS: This is a prospective, consecutive, observational, descriptive and analytical, non-randomized, qualitative study that evaluated the levels of anti-HBs antibodies in IBD patients at the Interdisciplinary Inflammatory Bowel Disease Clinic of the Family and Community Health Unit of UNIVALI - Itajaí, Santa Catarina. RESULTS: Thirty-six patients were vaccinated against hepatitis B virus (HBV), of which 29 were female. The average age was 46.2 years. Regarding the type of IBD, twenty-four patients had Crohn's disease and the duration of inflammatory bowel disease was 74 months. Fifteen patients were on concomitant immunosuppressive therapy. The effective response rate to HBV vaccine was 72.2%, verified by anti-HBs titration ≥10 UI/L. Statistical analysis revealed a negative response to vaccination in patients with Crohn's disease and immunosuppressive drugs. CONCLUSION: The success rate of HBV immunization in IBD patients is low compared to the general population. Type of disease and use of immunosuppressive drugs appear to influence the vaccine response.

RESUMO CONTEXTO: Os pacientes com doenças inflamatórias intestinais (DII) vacinados para hepatite B possuem baixa taxa de sucesso em alcançar níveis protetores de anticorpos. Os principais fatores sugeridos para isso são a própria DII e o uso de medicamentos imunossupressores. OBJETIVO: Avaliar a titulação de anticorpos anti-HBs e verificar fatores associados a efetividade da vacinação contra hepatite B em pacientes com DII. MÉTODOS: Trata-se de um estudo prospectivo e consecutivo, de caráter observacional, descritivo e analítico, não-randomizado, qualiquantitativo, que avaliou a titulação de anticorpos anti-HBs em pacientes portadores de DII no Ambulatório Interdisciplinar de Doença Inflamatória Intestinal da Unidade de Saúde da Família e Comunitária da UNIVALI - Itajaí, Santa Catarina. RESULTADOS: Trinta e seis pacientes foram vacinados contra o vírus da hepatite B (VHB), destes, 29 eram do sexo feminino. A média de idade foi de 46,2 anos. Em relação ao tipo de DII, 24 pacientes eram portadores de doença de Crohn e o tempo médio de doença inflamatória intestinal encontrado foi de 74 meses. Quinze pacientes estavam em uso de terapia imunossupressora concomitante à vacinação. A taxa de resposta à vacina contra o VHB foi de 72,2%, verificada através de titulação de anti-HBs ≥10 UI/L. A análise estatística revelou uma resposta negativa à vacinação em pacientes em uso de medicamentos imunossupressores e portadores de doença de Crohn. CONCLUSÃO: A taxa de sucesso na imunização contra o VHB em pacientes com DII é baixo quando comparado à população em geral. Tipo de doença e uso de medicamentos imunossupressores parecem desempenhar influência na resposta vacinal.

Serological profile of John Cunningham virus (JCV) in patients with multiple sclerosis / Perfil sorológico do vírus John Cunningham (JCV) em pacientes com esclerose múltipla

ABSTRACT Treatment options for multiple sclerosis (MS) have changed over the last few years, bringing about a new category of drugs with more efficient profiles. However, these drugs have come with a whole new profile of potential adverse events that neurologists have to learn well and quickly. One of the most feared complications of these MS treatments is progressive multifocal leukoencephalopathy caused by the reactivation of the John Cunningham virus (JCV). Objective: To identify the serologic profile of JCV in patients with MS. Methods: Data on serum antibodies for JCV were obtained using the enzyme-linked immunosorbent assay provided by the STRATIFY-JCV program. Results: A total of 1,501 blood tests were obtained from 1,102 patients with MS. There were 633 patients (57.1%) who were positive for antibodies for JCV and 469 patients who were negative (42.9%). Twenty-three patients became positive after initially having negative JCV antibody status. The rate of seroconversion was 18.5% over 22 months. Conclusion: The JCV serologic profile and seroconversion in Brazilian patients were similar to those described in other countries.

RESUMO As opções terapêuticas para esclerose múltipla (EM) modificaram-se ao longo dos últimos anos, trazendo uma nova categoria de drogas com melhor perfil de eficácia. No entanto, estas drogas vieram com um novo perfil de potenciais eventos adversos que exigem que o neurologista os reconheça bem e rapidamente. Uma das complicações mais temidas destes tratamentos para a EM é a leucoencefalopatia multifocal progressiva (LEMP), causada pela reativação do vírus John Cunningham (JCV). Objetivo: Identificar o perfil sorológico de JCV em pacientes com EM. Métodos: Dados sorológicos de JCV foram obtidos através do ensaio por enzimas imuno-adsorvidas (ELISA) fornecido pelo programa STRATIFY-JCV. Resultados: Um total de 1.501 testes sanguíneos foram obtidos de 1.102 pacientes com EM. O grupo teve 633 pacientes (57,1%) soropositivos para anticorpos anti-JCV e 469 pacientes negativos (42,9%). Vinte e três pacientes se tornaram posivitos após resultados iniciais negativos para anticorpos anti-JCV. A taxa de soroconversão foi 18,5% em 22 meses. Conclusão: O perfil sorológico do JCV e a soroconversão nos pacientes brasileiros foi semelhante àquela descrita em outros países.

Toxoplasmosis diseminada en un paciente con trasplante de corazón a pesar de la profilaxis con trimetoprim-sulfametoxazol / Disseminated toxoplasmosis in a heart transplant patient despite cotrimoxazole prophylaxis: A case report

Resumen Se reporta el caso de un paciente de sexo masculino, de 61 años de edad, quien ocho meses después de someterse a un trasplante de corazón presentó una enfermedad sistémica con compromiso del sistema nervioso central y del sistema inmunológico, así como de pulmón, riñón, colon y piel, y a quien finalmente se le diagnosticó toxoplasmosis diseminada, a pesar de haber recibido profilaxis con trimetoprim-sulfametoxazol, debido a que el órgano provenía de un donante positivo para toxoplasmosis siendo él un receptor negativo. Se discuten las opciones de profilaxis en nuestro medio.

Abstract We report the case of a 61 year-old male who underwent heart transplantation eight months before developing a systemic condition with central nervous system, lung, kidney, colonic, cutaneous, and hematologic involvement, found to be secondary to a systemic toxoplasmosis despite co-trimoxazole prophylaxis in a previous-to-transplant seronegative patient receiving a heart from a seropositive donor. A review of prophylactic options in our environment is discussed.

Predictors of HBeAg seroconversion after long-term nucleos(t)ide analogues treatment for chronic hepatitis B: a multicenter study in real clinical setting

ABSTRACT Aims: To evaluate the HBeAg seroconversion rate in real clinical setting and explore its predictors in long-term nucleos(t)ide analogues (NAs) treatment for chronic hepatitis B (CHB). Methods: 251 patients were recruited from January 2001 to September 2009 in four hospitals in Hebei province, China, for this retrospective study. Clinical and laboratory data before and after treatment with lamivudine (LAM, 100 mg daily), adefovir (ADV, 10 mg daily), telbivudine (LDT, 600 mg daily), entecavir (ETV, 0.5 mg daily), and LAM/ADV combination were compared among three groups according to treatment outcomes: synchronous HBeAg loss and HBeAg seroconversion, anti-HBe development after treatment, and no anti-HBe. Adherence was also evaluated. Results: In real clinical setting, cumulative HBeAg seroconversion rates were 14.3%, 32.7%, 43.0%, 46.9%, and 50.5% after 1, 2, 3, 5, and 8 years, respectively. 45 patients (17.9%) were non-adherent. Adherence (p < 0.001, Hazard Ratio (HR) = 2.203), elevated alanine aminotransferase (ALT) levels (p < 0.001, HR = 2.049), and non-vertical transmission (p = 0.006, HR = 1.656) were predictors of HBeAg seroconversion. Conclusion: Adherence, elevated ALT, and non-vertical transmission are predictors of HBeAg seroconversion in CHB patients treated with NAs.

Evolution of hepatitis B serological markers in HIV coinfected patients: a case study

ABSTRACT OBJECTIVE To describe the evolution of serological markers among HIV and hepatitis B coinfected patients, with emphasis on evaluating the reactivation or seroreversion of these markers. METHODS The study population consisted of patients met in an AIDS Outpatient Clinic in São Paulo State, Brazil. We included in the analysis all HIV-infected and who underwent at least two positive hepatitis B surface antigen serological testing during clinical follow up, with tests taken six months apart. Patients were tested with commercial kits available for hepatitis B serological markers by microparticle enzyme immunoassay. Clinical variables were collected: age, sex, CD4+ T-cell count, HIV viral load, alanine aminotransferase level, exposure to antiretroviral drugs including lamivudine and/or tenofovir. RESULTS Among 2,242 HIV positive patients, we identified 105 (4.7%) patients with chronic hepatitis B. Follow up time for these patients varied from six months to 20.5 years. All patients underwent antiretroviral therapy during follow-up. Among patients with chronic hepatitis B, 58% were hepatitis B “e” antigen positive at the first assessment. Clearance of hepatitis B surface antigen occurred in 15% (16/105) of patients with chronic hepatitis B, and 50% (8/16) of these patients presented subsequent reactivation or seroreversion of hepatitis B surface antigen. Among hepatitis B “e” antigen positive patients, 57% (35/61) presented clearance of this serologic marker. During clinical follow up, 28.5% (10/35) of those who initially cleared hepatitis B “e” antigen presented seroreversion or reactivation of this marker. CONCLUSIONS Among HIV coinfected patients under antiretroviral therapy, changes of HBV serological markers were frequently observed. These results suggest that frequent monitoring of these serum markers should be recommended.

High seroconversion rates in Trypanosoma cruzi chronic infection treated with benznidazole in people under 16 years in Guatemala

Abstract INTRODUCTION: Geographical, epidemiological, and environmental differences associated with therapeutic response to Chagas etiological treatment have been previously discussed. This study describes high seroconversion rates 72 months after benznidazole treatment in patients under 16 years from a project implemented by Doctors without Borders in Guatemala. METHODS: An enzyme-linked immunosorbent assay was used to detect Trypanosoma cruzi IgG antibodies in capillary blood samples from patients 72 months after treatment. Fisher's exact test was used to establish association between characteristics, such as sex, age, and origin of patients, and final seroconversion. Kappa index determined concordance between laboratory tests. The level of significance was set to 5%. RESULTS: Ninety-eight patients, aged 6 months to 16 years, were available for follow-up. Sex and origin were not associated with seroconversion. Individuals older than 13 were more prone to maintain a positive result 72 months after treatment, although results were not highly significant. Laboratory tests presented elevated Kappa concordance (95% CI) = 0.8290 (0.4955-1), as well as high (97%) seroconversion rates. CONCLUSIONS: The high seroconversion rate found in this study emphasizes the importance of access to diagnosis, treatment, and follow-up of individuals affected by Chagas disease. Moreover, it contradicts the idea that it is not possible to achieve a cure with the currently available drugs. This study strongly supports expanding programs for patients infected with T. cruzi in endemic and non-endemic countries.

Transmission of visceral leishmaniasis in dogs in a risk area of the metropolitan region of Belo Horizonte, Minas Gerais, Brazil / Transmissão da leishmaniose visceral em cães em área de risco da Região Metropolitana de Belo Horizonte, Minas Gerais, Brasil

Visceral leishmaniasis (VL) has spread rapidly across cities in the metropolitan region of Belo Horizonte. The aim of this study was to investigate VL dynamics in a prospective cohort study of dogs in Juatuba, between 2010 and 2011, to confirm the incidence of Leishmania infantum, and to assess possible risk factors associated with infection. An observational and prospective closed cohort study was performed using serology testing in dogs, randomly selected from the whole municipality. All seronegative dogs, or dogs with inconclusive results were monitored using indirect immunofluorescence (IIF) at 6-month intervals. The dog's owners completed a semi-structured questionnaire to assess possible causal factors of seroconversion, and the responses were assessed using logistic regression. The canine incidence coefficient was 206/1,000 dogs per year (CI: 178-238), and a cluster was identified in an area with a high concentration of seropositive dogs, but a low overall canine population. Large dogs were identified as a risk factor and the following variables were identified as protection factors: dogs aged over 4 years, daily peridomicile cleaning, and better socioeconomic conditions. VL is spreading over a large area in Juatuba in a short period of time.(AU)

A leishmaniose visceral (LV) expandiu-se de forma rápida e extensa pelos municípios da Região Metropolitana de Belo Horizonte. Objetivou-se estudar a dinâmica da LV em uma coorte prospectiva de cães em Juatuba, entre 2010 e 2011, para verificar a incidência e fatores de risco associados à infecção por Leishmania infantum. Foi feito um estudo observacional e prospectivo de coorte fechada por meio de análise sorológica em cães selecionados aleatoriamente em todo o município, com acompanhamento semestral dos resultados soronegativos e indeterminados na imunofluorescência indireta (IFI). Usou-se questionário semiestruturado junto aos proprietários de cães para avaliação da soroconversão e dos fatores determinantes a essa, por meio da regressão logística. O coeficiente de incidência canina foi de 206/1000 cães.ano (IC: 178 - 238), e foi identificado cluster em área com elevada concentração de cães soropositivos, mas com baixa densidade populacional canina. A variável cão de porte grande foi identificada como fator de risco, e as variáveis idade do cão superior a quatro anos, limpeza diária do peridomicílio e melhores condições socioeconômicas como fatores de proteção. A infecção por LV está ocorrendo em curto período de tempo e com ampla distribuição em Juatuba.(AU)

Transmission, serologic and tissue responses in chickens vaccinated with Mycoplasma gallisepticum F strain (MG-F) / Transmissão, resposta sorológica e tecidual de poedeiras vacinadas com Mycoplasma gallisepticum cepa F

MG-F protects chickens from MG Mycoplasmosis and monitoring is done by serology (SAR and ELISA) and PCR. Histopathology is used to evaluate bird response to MG. This study evaluated MG-F profile vaccination in SPF chicken. This trial used 100 chickens, being 40 unvaccinated (G1), 40 eye-drop vaccinated at 8 weeks of age with MG-F ( Ceva Animal Health , São Paulo , SP , Brazil ) (G2) and 20 immunized by contact (G3) . Samples were obtained on the 8th, 12th, 15th, 18th, 20th and 24th week for SAR, ELISA and PCR. Fragments of trachea and air sac, for microscopy, were got after necropsies on the 15th and 24th week. Up to 12 weeks there was no significant difference among groups by SAR. SAR reactions appeared from the 15th week with these averages: G1 (1.7, 1.76 , 0.1, 0.15) , G2 (7.81, 7.65, 8.25, 6.29) and G3 (8.1, 8.5, 9.5, 6.16), while by ELISA it occurred after the 18th week with optical densities averages: G1 (0.19, 0.14, 0.16) , G2 (0.47, 0.45, 0.41) and G3 (0.55, 0.51, 0.51) . Positivity in G3 by PCR occurred seven weeks after exposure. At the 15th week the air sac score means were 0.20, 0.55, and 0.32 and 24th week were 0.15, 0.80 and 0.66 (p>0.05). For trachea, G2 (0.48) yielded higher score average than G1 (0.10) and G3 (0.00) on the 15th week. Changes in G3 were seen only at 24th week, being this average (1.00) significantly different (p<0,05) from G1 (0.08) and G2 (0.46). SAR and PCR detected MG-F in G3 earlier than ELISA...

Mycoplasma gallisepticum cepa F (MG-F) é altamente utilizada em vacinação de poedeiras. MG-F confere bons níveis de proteção às galinhas, deslocando MG de campo ou diminuindo o número deles no trato respiratório. Soroaglutinação Rápida (SAR), ELISA e PCR são testes no monitoramento da micoplasmose, enquanto a histopatologia, mesmo não sendo rotineira, é usada para avaliar a resposta das aves à infecção por MG. O objetivo deste estudo foi avaliar a transmissibilidade, soroconversão e alterações teciduais de MG-F em galinhas. Um total de 100 galinhas SPF foi utilizado, sendo 40 delas não vacinadas (G1), 40 vacinadas na 8ª semana de idade com MG-F (Ceva Saúde Animal, São Paulo/SP, Brasil) (G2) e 20 imunizadas por contato com aves do G2 (G3). Soros e suabes traqueais foram obtidos na 8ª, 12ª, 15ª, 18ª, 20ª, 24ª semana para monitoramento por SAR, ELISA e PCR. Fragmentos de traqueia e saco aéreo, para microscopia, foram feitas após necropsias na 15ª e 24ª semana. Até a 12ª semana não houve diferença significativa entre os grupos pela SAR. Houve reação a SAR a partir da 15ª semana com as seguintes médias: G1 (1,7; 1,76; 0,1; 0,15), G2 (7,81; 7,65; 8,25; 6,29) e G3 (8,1; 8,5; 9,5; 6,16), enquanto por ELISA a soroconversão ocorreu a partir da 18ª semana com médias de densidades óticas de G1 (0,19; 0,14; 0,16), G2 (0,47; 0,45; 0,41) e G3 (0,55; 0,51; 0,51). Todas as aves do G3 apresentaram positividade pela PCR sete semanas após exposição. Não houve diferença significativa entre as medias dos escores de saco aéreo entre os grupos, na 15ª semana (0,20; 0,55; 0,32) e 24ª semana (0,15; 0,80 e 0,66). Em relação à traqueia, G2 apresentou média maior na 15ª semana (0,48) que G3 (0,00) e G1 (0,10). Alterações em G3 foram observadas somente na 24ª semana onde as médias foram de 0,08(G1); 0,46 (G2) e 1,00 (G3), havendo significância (p<0,05) entre G1 e G3. SAR e PCR foram capazes de detectar a transmissão de MG-F de forma precoce em relação ao ELISA...

Interspecific transmission of small ruminant lentiviruses from goats to sheep

This study was conducted in order to evaluate the transmission of caprine lentivirus to sheep using different experimental groups. The first one (colostrum group) was formed by nine lambs receiving colostrum from goats positive for small ruminant lentiviruses (SRLV). The second group (milk group) was established by nine lambs that received milk of these goats. Third was a control group, consisting of lambs that suckled colostrum and milk of negative mothers. Another experimental group (contact group) was formed by eight adult sheep, confined with two naturally infected goats. The groups were monitored by immunoblotting (IB), enzyme-linked immunosorbent assay (ELISA), agar gel immunodiffusion (AGID) and nested polymerase chain reaction (nPCR). All lambs that suckled colostrum and milk of infected goats and six sheep of the contact group had positive results in the nPCR, although seroconversion was detected only in three of the exposed animals, with no clinical lentiviruses manifestation, in 720 days of observation. There was a close relationship between viral sequences obtained from infected animals and the prototype CAEV-Cork. Thus, it was concluded that SRLV can be transmitted from goats to sheep, however, the degree of adaptation of the virus strain to the host species probably interferes with the infection persistence and seroconversion rate.

A randomised double-blind clinical trial of two yellow fever vaccines prepared with substrains 17DD and 17D-213/77 in children nine-23 months old

This randomised, double-blind, multicentre study with children nine-23 months old evaluated the immunogenicity of yellow fever (YF) vaccines prepared with substrains 17DD and 17D-213/77. YF antibodies were tittered before and 30 or more days after vaccination. Seropositivity and seroconversion were analysed according to the maternal serological status and the collaborating centre. A total of 1,966 children were randomised in the municipalities of the states of Mato Grosso do Sul, Minas Gerais and São Paulo and blood samples were collected from 1,714 mothers. Seropositivity was observed in 78.6% of mothers and 8.9% of children before vaccination. After vaccination, seropositivity rates of 81.9% and 83.2%, seroconversion rates of 84.8% and 85.8% and rates of a four-fold increase over the pre-vaccination titre of 77.6% and 81.8% were observed in the 17D-213/77 and 17DD subgroups, respectively. There was no association with maternal immunity. Among children aged 12 months or older, the seroconversion rates of 69% were associated with concomitant vaccination against measles, mumps and rubella. The data were not conclusive regarding the interference of maternal immunity in the immune response to the YF vaccine, but they suggest interference from other vaccines. The failures in seroconversion after vaccination support the recommendation of a booster dose in children within 10 years of the first dose.

Immune response to the mumps component of the MMR vaccine in the routine of immunisation services in the Brazilian National Immunisation Program

A non-controlled longitudinal study was conducted to evaluate the combined vaccine against measles, mumps and rubella (MMR) immunogenicity in 150 children vaccinated in the routine of three health units in the city of Rio de Janeiro, Brazil, 2008-2009, without other vaccines administered during the period from 30 days before to 30 days after vaccination. A previous study conducted in Brazil in 2007, in 1,769 children ranging from 12-15 months of age vaccinated against yellow fever and MMR simultaneously or at intervals of 30 days or more between doses, had shown low seroconversion for mumps regardless of the interval between administration of the two vaccines. The current study showed 89.5% (95% confidence interval: 83.3; 94.0) seroconversion rate for mumps. All children seroconverted for measles and rubella. After revaccination, high antibody titres and seroconversion rates were achieved against mumps. The results of this study and others suggest that two MMR doses confer optimal immunoresponses for all three antigens and the possible need for additional doses should be studied taking into account not only serological, but also epidemiological data, as there is no serological correlate of protection for mumps.

Hepatitis B virus surface antigen seroconversion in HIV-infected individual after pegylated interferon-alpha treatment: a case report

Hepatitis B virus (HBV) infects from 6 to 14% of HIV-infected individuals. Concurrent HIV/HBV infection occurs due to the overlapping routes of transmission, particularly sexual and parenteral. HIV-infected patients that have acute hepatitis B have six times greater risk of developing chronic hepatitis B, with higher viral replication, rapid progression to end-stage liver disease and shorter survival. The coinfection is also associated with poor response to hepatitis B treatment with interferon-alpha and increased liver toxicity to the antiretroviral therapy. Herein, we describe the case of a 35-year-old man who engages in sex with men and presented with newly diagnosed HIV-1, serological markers for acute hepatitis B and progression to chronic hepatitis B infection (HBsAg+ > 6 months, high alanine aminotransferase levels and moderate hepatitis as indicated by liver biopsy). Lacking indication of antiretroviral treatment (CD4 768 cells/mm 3 ), he was treated with pegylated-interferon alpha2b (1.5 mg/kg/week) by subcutaneous injection for 48 weeks. Twelve weeks after treatment, the patient presented HBeAg seroconversion to anti-HBe. At the end of 48 weeks, he presented HBsAg seroconversion to anti-HBs. One year after treatment, the patient maintained sustained virological response (undetectable HBV-DNA). The initiation of antiretroviral therapy with nucleosides and nucleotides is recommended earlier for coinfected individuals. However, this report emphasizes that pegylated interferon remains an important therapeutic strategy to be considered for selected patients, in whom the initiation of HAART may be delayed.(AU)

ELFA IgG anti-Toxoplasma y PCR anidada para el diagnóstico de toxoplasmosis en mujeres gestantes de Sincelejo, Colombia / ELFA anti-Toxoplasma IgG and nested PCR for the diagnosis of toxoplasmosis in pregnant women from Sincelejo, Colombia

Introducción. La vigilancia serológica de la toxoplasmosis no se incluye comúnmente en el control prenatal de las mujeres gestantes del departamento de Sucre; además, las técnicas usadas para el diagnóstico de la toxoplasmosis congénita no tienen suficiente sensibilidad para detectar los casos activos con el fin de instaurar un tratamiento oportuno y, así, reducir las secuelas en el recién nacido. El objetivo de este trabajo fue utilizar la amplificación de ADN de T. gondii mediante la técnica de reacción en cadena de la polimerasa (PCR) anidada en muestras de sangre de mujeres gestantes seronegativas de Sincelejo, para detectar la presencia del parásito. Materiales y métodos. La PCR anidada se realizó durante un período de 17 meses a partir del ADN extraído de las muestras de sangre de 100 mujeres gestantes de Sincelejo, seronegativas por la prueba ELFA (Enzyme-Linked Fluorescent Assay) IgG ant-Toxoplasma. Resultados. Se detectó ADN de T. gondii en 12 de las 100 mujeres gestantes incluidas en el estudio. Fue posible contactar para seguimiento a siete de ellas; en cuatro se detectaron títulos de anticuerpos IgG, que correspondían a la seroconversión de mujeres gestantes positivas por PCR. Conclusiones. La utilidad de la técnica de PCR en la detección de ADN de T. gondii en muestras de sangre periférica de mujeres gestantes con resultados negativos por la prueba ELFA IgG anti-Toxoplasma. Esta investigación demuestra la importancia de combinar las pruebas serológicas con técnicas moleculares para mejorar el diagnóstico de la infección por T. gondii.

Introduction: Toxoplasmosis is a worldwide disease caused by the protozoan parasite Toxoplasma gondii, which can produce serious damage in immune compromised patients and congenitally infected newborns. Serological screening for T. gondii infection is not currently included in the routine prenatal control for pregnant women in the department of Sucre; moreover, techniques used for diagnosis of congenital toxoplasmosis do not show enough sensitivity in the detection of active cases of toxoplasmosis in order to offer opportune treatment and to reduce the consequences of this infection in the newborn. Objective: To detect DNA of Toxoplasma gondii by nested PCR assay in peripheral blood samples of seronegative pregnant women from Sincelejo, Sucre. Materials and methods: Nested PCR assay was done using DNA extracted from peripheral blood samples of 100 seronegative pregnant women by Elfa anti-Toxoplasma IgG assay from the city of Sincelejo, throughout a 17 month period. Results: T. gondii DNA was detected in 12 of the 100 pregnant women included in this study. It was possible to follow 7 of them, and only 4 showed high titles of IgG antibodies obtaining an overall seroconversion of 57,1% in positive pregnant women by the PCR assay. Conclusions: These results demonstrate the utility of a PCR test to detect Toxoplasma gondii DNA in peripheral blood samples of seronegative pregnant women by ELFA anti-Toxoplasma IgG test. This research also confirms the importance of combining serological tests with molecular techniques to improve the diagnosis of Toxoplasma gondii infection.

Falla en la producción de anticuerpos con la vacuna del virus de la hepatitis B en pacientes dializados: incidencia y factores asociados / Failure in the antibodies production with hepatitis B vaccine in dialyzed patients: incidence and associated factors

Objetivo: conocer la incidencia de no seroconversión, después de la vacunación para Hepatitis B, en pacientes en diálisis y establecer los factores asociados con la falta de formación de anticuerpos. Metodología: estudio multicéntrico de cohorte retrospectiva en Medellín. Se incluyeron pacientes con falla renal crónica que iniciaron hemodiálisis o diálisis peritoneal entre enero 2006 y junio 2008. Esquema de vacunación: 4 dosis de 40 mcg Hepavax-Gene®, con medición de anticuerpos a las 4 semanas. Se consideró falta de respuesta: títulos < 10 U. Se analizó: género, edad, raza, diabetes, transfusiones, eritropoyetina, creatinina, ferritina, hemoglobina, albúmina y tipo de diálisis. Se hizo regresión logística binaria para factores asociados con respuesta a la vacunación y una regresión lineal múltiple “stepwise” para predecir los niveles de anticuerpos. Resultados: se incluyeron 237 pacientes. Alcanzaron títulos protectores de anticuerpos 153 pacientes (63.9%). La fórmula de predicción de respuesta es: Ln Y = (1.88) + (0.97 X Albúmina) – (0.00024 X Edad) – (0.097 X Creatinina) – (0.47 X mujer) – (0.49 X Hemodiálisis), Y= Título Anticuerpos. La albúmina con un nivel mayor de 3 g/dl se asoció con niveles de títulos > 10 U. OR = 4.92, (I.C. 95%, 2.09- 12.37). Conclusiones: la incidencia de seroconversión después de la vacunación contra hepatitis B en pacientes en diálisis es del 63%. La edad avanzada (> 65 años) y la hipoalbuminemia (<3 g/dl) se asociaron a una menor respuesta a la vacunación.

Objective: to get to know the incidence of non-seroconversion after vaccination for hepatitis B in dialysis patients, and to establish the associated factors with the lack of antibody production. Methods: multicenter retrospective cohort study in Medellin. Patients with chronic renal failure who started hemodialysis or peritoneal dialysis between January 2006 and June 2008 were included. Vaccination schedule: 4 doses of 40 mcg HepavaxGene ®, with measurement of antibodies 4 weeks later. A lack of response was considered if: titles < 10 U. We analyzed gender, age, race, diabetes, blood transfusions, erythropoietin, creatinine, ferritin, hemoglobin, albumin, and type of dialysis. Binary logistic regression was done to identify associated factors with the vaccination response and multiple linear regression "stepwise" to predict the levels of antibodies. Results: 237 patients were included. That reached protective antibody titers 153 patients (63.9%). The response prediction formula is: Ln Y = (1.88) + (0.97 X Albumin) ­ (0.00024 X Age) ­ (0.097 X Creatinine) ­ (0.47 X Women) ­ (0.49 X Hemodialysis), Y= antibody title. The albumin greater than 3 g/dl was associated with titers greater than 10 U. OR = 4.92, (95% CI 2.09 - 12.37). Conclusions: the incidence of the seroconversion after vaccination against the virus of hepatitis B in patients in dialysis is 63%. The elderly (> 65 years old) and hypoalbuminemia (<3 g/dl) were associated to a smaller response to the vaccination.>< 3 g/dl) were associated to a smaller response to the vaccination.