Modifications in a Reference Freeze-Dried Direct Agglutination Test to Improve Visceral Leishmaniasis Detection.

Currently, a significantly lower temperature (35°C) than initially established (56°C) is indicated as the maximum temperature storage for the commercial reference visceral leishmaniasis (VL) freeze-dried direct agglutination test (FD-DAT). Despite an approximately 50% loss in the number of promastigotes in an FD-DAT batch that expired 7 years earlier, the promastigotes maintained a similar morphology to the equivalent valid batch implying most likely that auto-agglutination, rather than aging, is the main reason for expiry. The substitution of normal saline which was initially recommended for reconstitution, by citrate-saline/formaldehyde (CSF) as an anti-clumping/preservative agent resulted in restoration of validity comparable with that of the freeze-dried original or the liquid direct agglutination test (LQ-DAT) version (Friedman ANOVA test = 1.0588; P = 0.5890). Following a similar reconstitution procedure as for the 7-year expired antigen, using significantly lower promastigote concentration (1.4 × 107/mL) than in the non-expired (9.0 × 107/mL), good reliability for VL detection and stability at 4°C (> 12 months) were achieved. In comparison with the original version using normal saline ($32.0/vial), the cost-effectiveness of the FD-DAT was appreciably improved by the CSF incorporation and lowering of promastigote concentration per unit suspension medium ($12.8/vial). With diagnostic reliability comparable with the full-out titration used, FD-DAT procedure based on single sample dilution at the VL cutoff (1:3,200) permitted the use of significantly smaller antigen volumes (0.1 mL vs. > 1.5 mL), therefore contributing to a further reduction in the application cost. The successful replacement of ß-mercaptoethanol (ß-ME) by urea (T = 21.00; P = 0.0868) provided the required safety for the test procedure similar to the widely applied LQ-DAT.

Detection of Oral Entamoeba Gingivalis and Trichomonas Tenax in Adult Quilombola Population with Periodontal Disease / Detección de Entamoeba Gingivalis oral y Trichomonas Tenax en población de quilombola adulta con enfermedad periodontal

Abstract: The objective was to analyze the periodontal condition severity and the occurrence of pathogenic microorganisms in the oral cavity of an adult population of an Afrodescent Community of northeastern Brazil. This is an observational and cross- sectional study performed through an oral clinical examination, using a standardized clinical record. For the subjects with periodontal disease, the bacterial biofilm was collected in a Petri dish containing 0.9% physiological solution to detect the presence of microorganisms Entamoeba gingivalis and Trichomonas tenax, and later observed under an optical microscope. Statistical analysis was performed by calculating the prevalence of periodontal disease and the frequency of the protozoa in the bacterial biofilm. Statistical significance of the relationships researched was verified by Fisher's exact test. It was evaluated 29 subjects pertaining to the Quilombola Patioba community, aged 35 to 44 years. The results showed that among the adults of the community, there was a high prevalence of periodontal disease (75.86%), being higher in the 1st and 6th sextants of the Community Periodontal Index (CPI). E. gingivalis positivity occurred in most sextants affected by gingivitis, while in the condition of periodontitis, this microorganism was not present in the 3rd, 4th and 6th sextants. In all sextants affected by periodontal disease, T. Tenax was observed when associated with gingivitis. It is worth mentioning the begging of the elaboration of health policies, social and professional commitment that foster a greater promotion of oral health and quality of life for the quilombolas of northeastern Brazil.

Resumen: El objetivo fue analizar la severidad de la condición periodontal y la aparición de microorganismos patógenos en la cavidad oral de una población adulta de una comunidad afrodescente del noreste de Brasil. Este es un estudio observacional y transversal realizado a través de un examen clínico oral, utilizando un registro clínico estandarizado. Para los sujetos con enfermedad periodontal, la biopelícula bacteriana se recogió en una placa de Petri que contenía una solución fisiológica al 0,9% para detectar la presencia de microorganismos Entamoeba gingivalis y Trichomonas tenax, y luego se observó bajo un microscopio óptico. El análisis estadístico se realizó calculando la prevalencia de la enfermedad periodontal y la frecuencia de los protozoos en la biopelícula bacteriana. La significación estadística de las relaciones investigadas se verificó mediante la prueba exacta de Fisher. Se evaluaron 29 sujetos pertenecientes a la comunidad Quilombola Patioba, de 35 a 44 años. Los resultados mostraron que entre los adultos de la comunidad, hubo una alta prevalencia de enfermedad periodontal (75.86%), siendo mayor en el sexto sexto y sexto del Índice periodontal comunitario (IPC). La positividad de E. gingivalis se produjo en la mayoría de los sextantes afectados por gingivitis, mientras que en la condición de periodontitis, este microorganismo no estaba presente en los sextantes tercero, cuarto y sexto. En todos los sextantes afectados por enfermedad periodontal, se observó T. Tenax cuando se asoció con gingivitis. Vale la pena mencionar el inicio de la elaboración de políticas de salud, compromiso social y profesional que promuevan una mayor promoción de la salud oral y la calidad de vida de las quilombolas del noreste de Brasil.

Type of light i sand fly captures (diptera: psychodidae) / Tipo de luz en la captura de flebotominos (Diptera: Psychodidae)

The number of visceral leishmaniasis cases has been gradually increasing in Brazil. One of the strategies to reduce the disease transmission is based on vector control. It is therefore of great epidemiological importance to develop more refined methods for monitoring and controlling its vectors, which are the phlebotomine sand flies. The present study evaluates the performance of traps using UV light or conventional incandescent, or white, light in sand flies captures. Traps baited with UV light caught higher numbers of sand flies than traps baited with white light, indicating the potential use of UV light, especially in locations of low sand flies densities.

El número de casos de leishmaniasis visceral en Brasil ha ido en aumento, y una de las estrategias para reducir la transmisión de esta enfermedad tiene como base el control de sus vectores. Por tanto, es de gran importancia epidemiológica desarrollar métodos más refinados para monitorear y controlar sus vectores, que son los flebotominos. El presente estudio compara la atracción ejercida por la luz UV en comparación con luz incandescente convencional, o luz blanca, en la captura de flebotominos. Las trampas adaptadas con luz UV capturaron un mayor número de mosquitos que las trampas adaptadas con luz blanca, lo que indica el uso potencial de la luz ultravioleta, especialmente en las localidades de baja densidad de flebotominos.