Species and biotype distribution of thermotolerant Campylobacters in animal reservoirs in Southern Chile

The prevalence of thermotolerant Campylobacters in mammals and birds from Southern Chile was determined. Campylobacters were isolated from 46.3% of the animals studied being C. jejuni biotipe 1 the most frequent (25.7%) followed by C. coli (17.4%) and C. jejuni biotipe 2 (3.2%).

Evaluation of enzyme-linked immunosorbent and alternative assays for detection of HIV antibodies using panels of Brasilian sera

Sera from 472 Brazilian subjects, confirmed to be either positive or negative for HIV antibodies and comprising the total clinical spectrum of HIV infection, were utilized in the evaluation of six commercially available enzyme-linked immunosorbent assays (ELISA), as well as of four alternative assays, namely indirect immunofluorescence (IIF), passive hemagglutination (PHA), dot blot and Karpas AIDS cell test. The sensitivities ranged from 100% (Abbott and Roche ELISA) to 84.2% (PHA) and the specificities ranged from 99.3% (IIF) to 80.2% (PHA). The sensitivity and specificity of the PHA and the sensitivity of the Karpas cell test were significantly lower than those of the other tests. Although the IFF and dot blot had good sensitivities and specificities, the six ELISA were more attractive than those tests when other parameters such as ease of reading and duration of assay were considered.

Reactividad a la histoplasmina en trabajadores de granjas avícolas en la provincia de Ciego de Avila, Cuba

Se realizo una encuesta epidemiológica mediante la prueba intradérmica de histoplasmina a 392 trabajadores de granjas avícolas y 265 de diferentes centros ocupacionales considerados sin riesgo profesional de exposición a Histoplasma capsulatum, agente etiológico de la histoplasinosis. Entre los trabajadores del primer grupo se detectó un 28,8% de positividad, mientras que en el segundo grupo se encontro un 13,2% de casos positivos; desde el punto de vista estadístico existió diferencia significativa entre ambos, lo que demuestra que los trabajadores de granjas avícolas son un grupo de riesgo de adquirir la infección por H capsulatum. Entre los trabajadores del grupo I se encontro un porcentaje de reactividad más alto en aquellos grupos ocupacionales que estaban más en contacto con las excretas de las aves. El tiempo de trabajo en la granja también parece influir en la reactividad a la prueba.

Fuentes de infeccion de histoplasmosis en la Isla de la Juventud, Cuba

El propósito del presente trabajo es reportar el aislamiento de Histoplasma capsulation, agente etiológico de la histoplasmosis, a partir del suelo de lugares habitados por murciélagos y gallinas en la Isla de la Juventud, Cuba. El hongo fue cultivado también a partir de los órganos de cuatro especies de murciélagos capturados en cuevas. La identificación de H. capsulatum se realizó mediante la conversión de la fase miceliana a levadura y por el test de exoantígenos. Se señala el valor epidemiológico de estos hallazgos en cuevas de gran importancia arqueológica, espeleológica y turística, así como el riesgo potencial que representan para la salud humana. Los autores concluyen con recomendaciones para evitar la infección por H. capsulatum en aquellas personas que por determinadas razones tengan que estar en contacto con estos ambientes contaminados.

Estudio clinico micologico de onimicosis en ancianos

Se realizó examen físico de las uñas a 210 ancianos y a aquellos que presentaron lesiones sugestivas de onicomicosis se les realizó toma de muestra con el objetivo de conocer los principales agentes causales, las características e incidencia de las lesiones. Se confirmó el diagnóstico mediante el aislamiento del agente causal en 74 de los casos procedentes principalmente de las uñas de los pies, para una incidencia de 35,2. La tinea pedis se presentó en el 25,7% de los casos, mientras que la enfermedad asociada más frecuente fue la Diabetes mellitus; entre las características clínicas de las uñas predominaron el engrosamiento, la pérdida del brillo y la aparición de estrías longitudinales. Existió una correspondencia significativa entre el examen microscópico directo y el cultivo. La especie de dermatofito predominate fue Trichophyton rubrum, mientras que Candida parapsilosis fue la más aislada entre las especies de Candida.

Relación entre la prueba intradermica de histoplasmina y los niveles de anticuerpos detectables por ELISA e immunodifusion

Se realizó un estudio prospectivo en 40 trabajadores de una granja avícola (grupo 1) considerados con riesgo de exposición a Histoplasma capsulatum, agente etiológico de la histoplasmosis, y en 16 individuos sin riesgo profesional de exposición a dicho agente (grupo 2). En ambos grupos se aplicó la prueba intradérmica de histoplasmina y se obtuvo el suero antes de su aplicación y a los 30 y 180 días después de realizada dicha prueba. Se determinó el nivel de anticuerpos anti-H. capsulatum mediante las técnicas de ELISA e inmunodifusión doble. En los dos grupos de población estudiados la aplicación intradérmica de histoplasmina, aún en los casos en que la respuesta fue positiva, no constituyó un estímulo antigénico suficiente para provocar un aumento en los niveles de anticuerpos anti-H. capsulation detectables por las técnicas serológicas empleadas. Los resultados obtenidos contribuyen a la mejor interpretación de la prueba de ELISA en el diagnóstico de la histoplasmosis.

Chicken as potential contamination source of Campylocacter lari in Iquitos, Peru

In order to know the importance of chicken as natural reservoir of Campylobacter lari in Iquitos, Peru; samples were obtained by cloacal swabs from 200 chickens and immediately placed into a semisolid enrichment medium; these were streaked on modified Skirrow Agar. The organism was isolated from 21 (10.5%) samples, corresponding 58.8% to biovar I and 41.2% to biovar II (Lior scheme). The results provide evidence that chicken appear to be prominent reservoirs of Campylobacter lari in Iquitos.

Cardiac beta-receptors in experimental Chagas' disease

Experimental Chagas' disease (45 to 90 days post-infection) showed serious cardiac alterations in the contractility and in the pharmacological response to beta adrenergic receptors in normal and T. cruzi infected mice (post-acute phase). Chagasic infection did not change the beta receptors density (78.591 ± 3.125 fmol/mg protein and 73.647 ± 2.194 fmol/mg protein for controls) but their affinity was significantly diminished (Kd = 7.299 ± 0.426 nM and Kd = 3.759 ± 0.212 nM for the control) p < 0.001. This results demonstrate that the alterations in pharmacological response previously reported in chagasic myocardium are related to a significantly less beta cardiac receptor affinity. During this experimental period serious cardiac cell alterations take place and functional consequences will be detected in the chronic phase.

Seroprevalence of HIV, HTLV-I/II and other perinatally-transmitted pathogens in Salvador, Bahia

Generation of epidemiological data on perinatally-transmitted infections is a fundamental tool for the formulation of health policies. In Brazil, this information is scarce, particularly in Northeast, the poorest region of the country. In order to gain some insights of the problem we studied the seroprevalence of some perinatally-transmitted infections in 1,024 low income pregnant women in Salvador, Bahia. The prevalences were as follow: HIV-1 (0.10%), HTLV-I/II (0.88%), T.cruzi (2.34%). T.pallidum (3.91%), rubella virus (77.44%). T.gondii IgM (2.87%) and IgG (69.34%), HBs Ag (0.6%) and anti-HBs (7.62%). Rubella virus and T.gondii IgG antibodies were present in more than two thirds of pregnant women but antibodies against other pathogens were present at much lower rates. We found that the prevalence of HTLV-I/II was nine times higher than that found for HIV-1. In some cases such as T.cruzi and hepatitis B infection there was a decrease in the prevalence over the years. On the other hand, there was an increase in the seroprevalence of T.gondii infection. Our data strongly recommend mandatory screening tests for HTLV-I/II, T.gondii (IgM), T.pallidum and rubella virus in prenatal routine for pregnant women in Salvador. Screening test for T.cruzi, hepatitis and HIV-1 is recommended whenever risk factors associated with these infections are suspected. However in areas with high prevalence for these infections, the mandatory screening test in prenatal care should be considered.

Carriage of the classical thermotolerant campylobacters in healthy domestic animals from Eastern Peru

Com o objetivo de conhecer a importância dos animais domésticos como reservatórios naturais dos clássicos campylobacters termotolerantes, amostras de fezes foram obtidas de mamíferos e aves do leste do Peru e imediatamente colocadas num meio de enriquecimento. Técnicas convencionais foram utilizadas para identificar C. jejuni ssp. jejuni, C. coli e C. lari. Campylobacter foi isolado em 26,5% dos animais estudados, sendo C. jejuni ssp. jejuni biovar I o mais freqüente (8,9%). O frango foi o reservatório mais importante destes microorganismos (54,0%).

Population dynamics and biting rhythm of the anthropophilic sandfly Lutzomyia cruciata (Diptera: Psychdidae) in Southeast, Mexico

Sandflies attracted by human bait were caught in an endemic focus of localized cutaneous leishmaniasis in the state of Campeche, Mexico. Catches were carried out monthly from February 1994 to January 1995 between 18:00 and 22:00 h. Lutzomyia cruciata was the only species caught. The highest population peak of Lu. cruciata was found in March with lesser peaks in February, December 1994, and January 1995. Maximum biting rate of Lu. cruciata was found between 18:00 and 19:00 h. The host-seeking females of Lu. cruciata were directly related to levels of humidity between 88 and 100%. Low and high temperature had a negative effect upon Lu. cruciata activity. The possible role of Lu. cruciata as vector of leishmaniasis in the state of Campeche, Mexico is discussed.

Norfloxacin monodose use in patients with cholera in Salta, Argentina

The use ofmonodose (800 mg) per os of Norfloxacin was evaluated in 32 patients with cholera at Salvador Mazza's Hospital, Salta, Argentina. It was considered the celerity in negativization of stool culture (100% of cases: 12 hours post administration), its efficiency along time (24/24 controlled patients were negative at 10th day) and MIC of isolated strains (100% of strains were sensitive: range 0.008 to 0.016 mug/ml). It was included oral administration of sorbitol 70% in peanut oil in order to study patients at 10th day's control. This method could be an alternative one in the study of asymptomatic carrier. Norfloxacin monodose shows good performance in early negativization of stool culture and it was also effective along the whole observation period, suggesting it could prevent carriage.

Use of doxycycline for leptospirosis after high-risk exposure in São Paulo, Brazil

A clinical trial pilot study, double-blinded, randomized, and controlled with a placebo to assess the effectiveness of oral doxycycline (200 mg, single dose) in preventing leptospirosis after high exposure to potentially contamined water was performed in São Paulo, SP, Brazil. Confirmed cases were defined as those with leptospira IgM antibody and symptoms; asymptomatic cases were those presenting with IgM antibodies but no symptoms; and suspected cases were individuals with symptoms but no IgM antibody. Forty subjects were given doxycycline and 42 were given placebo. In the drug-treated group there were 2 confirmed cases, 11 asymptomatic cases, and 6 suspected cases. In the placebo group there were 5 confirmed, 6 symptomatic, and 5 suspected cases. Even though we found a protective association of doxycycline for confirmed leptospirosis cases (RR = 2.3) and seroconversion only (RR = 2.0), the association was not statistically significant because of the small number of individuals enrolled in this pilot study. We observed that the 22% of the volunteers already had IgM antibodies to leptospirosis at the first sampling. Finally, the attack rate to confirmed, asymptomatic, and suspected cases of Leptospirosis was 8.5%, 22%, and 13%, respectively, in this population.

Genetic variation between susceptible and non-susceptible snails to Schistosoma infection using random amplified polymorphic DNA analysis (RAPDs)

Susceptibility of snails to infection by certain trematodes and their suitability as hosts for continued development has been a bewildering problem in host-parasite relationships. The present work emphasizes our interest in snail genetics to determine what genes or gene products are specifically responsible for susceptibility of snails to infection. High molecular weight DNA was extracted from both susceptible and non-susceptible snails within the same species Biomphalaria tenagophila. RAPD was undertaken to distinguish between the two types of snails. Random primers (10 mers) were used to amplify the extracted DNA by the polymerase chain reaction (PCR) followed by polyacrylamide gel electrophoresis (PAGE) and silver staining. The results suggest that RAPD represents an efficient means of genome comparison, since many molecular markers were detected as genetic variations between susceptible and non-susceptible snails.