Development of a syphilis serum bank to support research, development, and evaluation of syphilis diagnostic tests in the United States.

The Centers for Disease Control and Prevention's (CDC) Division of STD Prevention, in collaboration with the Association of Public Health Laboratories (APHL), is developing a nationally available syphilis serum repository for research of Food and Drug Administration (FDA)-cleared or investigational syphilis diagnostic assays in the United States. State and local public health laboratories (PHL) submitted de-identified residual sera with information on collection date, volume, storage conditions, freeze-thaw cycles, PHL serology results, reported syphilis stage and demographic details if available. Previous test results were blinded and sera (N = 152 reported syphilis stage, N = 131 unknown status) were tested at CDC using five FDA-cleared and one investigational syphilis tests. Treponemal and nontreponemal test sensitivity ranged from 76.3-100% and 63.2-100%, respectively, among staged specimens. The conventional treponemal assays showed high concordance of 95.4%. By providing syphilis stage and comprehensive serological test data, developed repository may serve as a valuable resource for diagnostic test validation studies.

Optimal detection of extended-spectrum ß-lactamase producers, carbapenemase producers, polymyxin-resistant Enterobacterales, and vancomycin-resistant enterococci from stools.

This study compared the impact of different approaches, namely, nonenrichment, nonselective enrichment, and selective (antibiotic-containing) enrichment steps, for detecting extended-spectrum ß-lactamase producing Enterobacterales (ESBL-E), carbapenemase-producing Enterobacterales (CPE), polymyxin-resistant Enterobacterales (PMR-E), and vancomycin-resistant enterococci (VRE) from spiked stools. The use of a nonselective 18-h enrichment broth culture significantly improved the recovery rate of all types of resistant bacteria after their plating onto selective media. In addition, the detection of ESBL-E, CPE, PMR-E, and VRE was further improved when using an enrichment step using antibiotic-supplemented broths respectively supplemented with cefotaxime (0.1 µg/mL), ertapenem (0.1 µg/mL), colistin (0.5 µg/mL), and vancomycin (1 µg/mL). Therefore, we showed here that a screening strategy based on a selective broth enrichment step significantly contributes to an increased rate of detection of multidrug-resistant bacteria, which may be crucial in term of improvement of infection control.

Prevalence of canine heartworm infection in Mississippi animal shelters.

Understanding diagnosis of heartworm disease in the context of animal shelters' needs and expectations is crucial for developing guidelines that specifically address the unique shelter population. Accurate and economical heartworm testing strategies are essential. However, current comprehensive guidelines for the management of heartworm disease in dogs are directed toward client-owned animals and do not address needs of animal shelters and other resource-scarce facilities. Additionally, testing recommendations do not take into account regional and local differences in heartworm prevalence across the United States that occur due to abiotic and biotic factors. The objective of this study was to determine the apparent prevalence of Dirofilaria immitis microfilaremia and antigenemia in dogs from Mississippi animal shelters. Further, we compare agreement between microfilaria and antigen testing in this population. We performed a cross-sectional study using canine serum and blood bank samples representative of the Mississippi shelter population. Microfilaria testing of whole blood included a blood smear and modified Knott test. Antigen testing of serum was performed using the DiroCHEK® antigen ELISA test. Analyses included descriptive and analytic statistics as well as Cohen's kappa for test agreement. A total of 283 whole blood samples and 363 serum samples, representing 363 dogs from 18 shelters in 17 Mississippi counties, were utilized in this study. Sixty-four (22.6%) whole blood samples demonstrated D. immitis microfilariae on the modified Knott test and 125 (34.4%) serum samples had detectable D. immitis antigen. Increasing age and low body condition were associated with antigen-positive test results. Only age was associated with microfilaria-positive test results. There was moderate agreement between the antigen ELISA test and the modified Knott microfilaria test and poor agreement between the antigen ELISA and the blood smear. This study provides the first known report of the prevalence of D. immitis microfilaremia and antigenemia in Mississippi shelter dogs. We observed that prevalence of both microfilaremia and antigenemia was significantly higher in these sampled dogs compared to previous reports for the owned canine population in Mississippi. Heartworm infection presents unique management challenges for animal shelters. Knowledge of the expected prevalence in the area can be utilized for management decisions related to prevention, testing, and treatment of dogs in shelter populations.

Aplicación de la Telemática en el monitoreo remoto de Bancos de Muestras Biológicas. Estudio Preliminar

Las serotecas son espacios destinados para el resguardo de Muestras Biológicas (MB) de procesos diagnósticos y científicos. El Instituto de Investigaciones en Ciencias de la Salud (IICS) cuenta con ocho congeladores de Ultra Baja Temperatura (UBT) distribuidos en dos serotecas. El sistema de monitoreo diseñado se evaluó durante cuatro meses, mientras registraba y enviaba alertas de tres UBT instalados en una de las serotecas y de su temperatura ambiente. Se recabó información de los usuarios respecto al rango de las temperaturas de cada UBT, tipo de MB almacenadas y su criterio de conservación. Se emplearon controladores de temperatura con sensores PT 100 conectados a un convertidor RS485/Ethernet en cada congelador. El sistema monitoreó, registró y alertó vía correo electrónico a los usuarios y técnicos biomédicos sobre los incidentes por temperaturas fuera del rango y falla de comunicación. En total se registraron 25 incidentes, 17 referentes al tiempo de apertura de puerta, 5 por temperatura elevada del ambiente y 3 por problemas en la conexión de red. La aplicación de la telemática fue determinante para monitorear en tiempo real las temperaturas de los congeladores UBT y del ambiente para garantizar que la cadena de frío no se vea afectada. De esta forma se cuenta con una herramienta que notifica a los usuarios de serotecas y biobancos los incidentes eléctricos o eventos que afecten el rango de temperatura necesario para la preservación de los materiales biológicos, permitiéndoles realizar una intervención oportuna y así garantizar la correcta preservación de las MB.

The serum banks are spaces used for the protection of Biological Samples (BS) of diagnostic and scientific processes. The Instituto de Investigaciones en Ciencias de la Salud (IICS) has eight Ultra Low Temperature (ULT) freezers distributed in two serum banks. The designed monitoring system was evaluated for four months, while recording and sending alerts of three ULTs installed in one of the serum banks and their ambient temperature. Information was collected from users regarding the temperature range of each ULT, type of stored BS and their conservation criteria. Temperature controllers with PT 100 sensors connected to an RS485/Ethernet converter were used in each freezer. The system monitored, recorded and alerted users and biomedical technicians via email about incidents due to temperatures outside the range and communication failure. In total, 25 incidents were recorded, 17 related to door opening time, 5 due to high ambient temperature and 3 due to network connection problems. The application of telematics was decisive in monitoring the temperatures of the ULT freezers and the environment in real time to ensure that the cold chain was not affected. In this way, there is a tool that notifies users of serum banks and biobanks of electrical incidents or events that affect the temperature range necessary for the preservation of biological materials, allowing them to perform a timely intervention and thus guaranteeing the correct preservation of the BS.

Estabilidade dos anticorpos anti-HIV em amostras de soro armazenadas por períodos de dois a dezoito anos / Stability of anti-HIV antibodies in serum samples stored for two to eighteen years periods

Introduction: The antibodies have an important role in the serodiagnosis, constituting the most widely used biomarkers to detect and confirm various diseases. Objective: To investigate the reproducibility of anti-human immunodeficiency virus (HIV) antibodies reactivity, to assess the stability of the sera samples stored at -20ºC for two to eighteen years. Method: Sera were collected in the period 1988-2004 for routine anti-HIV antibodies diagnostic testing. The remaining samples stored at -20ºC, were analyzed in this study. Serum sample stability was assessed by enzyme-linked immunosorbent assay/enzyme immunoassay (ELISA/EIA), indirect immunofluorescence assay (IFA), and Western blot (WB) for detecting anti-HIV antibodies. The previously found results (1988-2004) and those obtained in 2006 were subjected to Kappa index analysis. Result: In the period 1988-to 2004, the degree of concordance of the ELISA/EIA, IFA and WB results were considered, good (k = 0.80), regular (k = 0.35), and good (k = 0.63), respectively. Conclusion: Regarding HIV serologic test, the serum samples were stable for 18 years in ELISA/EIA and for 4 years in IFA technique, however, for the WB methodology it was not possible to determine the time of stability of the anti-HIV antibodies...

Introdução: Os anticorpos possuem papel fundamental no sorodiagnóstico e constituem os mais difundidos biomarcadores empregados na detecção e na confirmação de diversas doenças. Objetivo: Verificar a reprodutibilidade dos resultados de anticorpos contra o vírus da imunodeficiência humana (HIV) para avaliar a estabilidade dos soros armazenados a -20ºC durante período de dois a dezoito anos. Método: Os soros utilizados foram provenientes de amostras remanescentes da rotina diagnóstica para detecção de anticorpos anti-HIV, no período de 1988 a 2004, os quais estavam armazenados em freezer a -20ºC. A estabilidade das amostras de soro foi avaliada por meio de enzyme-linked immunosorbent assay/enzyme immunoassay (ELISA/EIA), imunofluorescência indireta (IFI) e Western blot (WB) para detecção de anticorpos anti-HIV, e os resultados dos testes realizados anteriormente (1988-2004) e os obtidos em 2006 foram submetidos à análise do índice Kappa. Resultado: No período de 1988-2004, os graus de concordância dos resultados do ELISA/EIA, IFI e WB foram considerados, respectivamente, bom (k = 0,80), regular (k = 0,35) e bom (k = 0,63). Conclusão: No que diz respeito à sorologia para HIV, as amostras de soro foram estáveis por 18 anos no ELISA/EIA e por quatro anos na técnica de IFI, no entanto, para a metodologia de WB, não foi possível determinar o tempo de estabilidade dos anticorpos anti-HIV...