Isolation and Identification of Western Equine Encephalomyelitis Virus from Mosquitoes by Tissue Culture Methods *

1958 ◽  
Vol 7 (2) ◽  
pp. 187-196 ◽  
Author(s):  
Hartwell H. Welsh ◽  
Beverly Jean Neff ◽  
Edwin H. Lennette
2003 ◽  
Vol 69 (6) ◽  
pp. 3492-3499 ◽  
Author(s):  
Yang Hong ◽  
Mark E. Berrang ◽  
Tongrui Liu ◽  
Charles L. Hofacre ◽  
Susan Sanchez ◽  
...  

ABSTRACT Contamination of retail poultry by Campylobacter spp. and Salmonella enterica is a significant source of human diarrheal disease. Isolation and identification of these microorganisms require a series of biochemical and serological tests. In this study, Campylobacter ceuE and Salmonella invA genes were used to design probes in PCR-enzyme-linked immunosorbent assay (ELISA), as an alternative to conventional bacteriological methodology, for the rapid detection of Campylobacter jejuni, Campylobacter coli, and S. enterica from poultry samples. With PCR-ELISA (40 cycles), the detection limits for Salmonella and Campylobacter were 2 � 102 and 4 � 101 CFU/ml, respectively. ELISA increased the sensitivity of the conventional PCR method by 100- to 1,000-fold. DNA was extracted from carcass rinses and tetrathionate enrichments and used in PCR-ELISA for the detection of Campylobacter and S. enterica, respectively. With PCR-ELISA, Salmonella was detected in 20 of 120 (17%) chicken carcass rinses examined, without the inclusion of an enrichment step. Significant correlation was observed between PCR-ELISA and cultural methods (kappa = 0.83; chi-square test, P < 0.001) with only one false negative (1.67%) and four false positives (6.67%) when PCR-ELISA was used to screen 60 tetrathionate enrichment cultures for Salmonella. With PCR-ELISA, we observed a positive correlation between the ELISA absorbance (optical density at 405 nm) and the campylobacter cell number in carcass rinse, as determined by standard culture methods. Overall, PCR-ELISA is a rapid and cost-effective approach for the detection and enumeration of Salmonella and Campylobacter bacteria on poultry.


2021 ◽  
Vol 10 (Supplement_2) ◽  
pp. S19-S19
Author(s):  
Johanny Contreras ◽  
Karina Rivera ◽  
María Castillo ◽  
Genara Santana ◽  
María Dolores Gil ◽  
...  

Abstract Background In October 2018, the Hispaniola Project was initiated to build local expertise in infection care and prevention at three pediatric oncology units (POUs) in Haiti and the Dominican Republic. Surveillance of healthcare-associated infections (HAI) was a central aim. Severe and prolonged neutropenia is a frequent risk factor for infections in oncology patients. Among HAIs, bacteremia is one of the most serious; bacteremia requires timely isolation and identification of the offending microorganism and the antimicrobial susceptibility. These diagnostic interventions allow informed therapeutic and prophylactic measures. Here, we report our experience in bacteremia in these 3 POUs. Methods We conducted prospective infection surveillance of all patients admitted to three POUs in Hispaniola Island. Blood culture methods followed standard national procedures. We used the 2018 US Centers for Disease Control National Healthcare Safety Network case definitions for primary laboratory-confirmed bloodstream infections (LCBI), and we categorized infections as healthcare-associated or present on admission (POA). We reviewed data collected from January 2019 to December 2020 and used descriptive statistics to report our results. Results Our review identified 66 LCBIs with an overall rate of 3.52 infections per 1000 patient-days. Of these, 40 (61%) were healthcare-associated, and 26 were POA. The majority (41, 62%) of patients were undergoing chemotherapy at the time of the infection, with induction being the most common phase (23). The most common oncologic diagnosis was acute lymphoblastic leukemia (43, 65%), followed by solid tumor (12, 18%). Fifty-three (80%) of the infections met the LCBI-1 criteria, with the other 13 categorized as LBCI-2. Of the 53 LCBI-1, 7 (13%) were considered related to mucosal barrier injury (MBI-LCBI 1 definition). The most commonly identified organisms were Klebsiella spp. (13, 19%) and coagulase-negative Staphylococcus (13, 19%). Antibiotic resistance was observed in many of the identified pathogens, with nearly half (25, 44%) of the 57 bacterial isolates having any resistance and a quarter (14, 25%) with resistance to multiple classes, including cephalosporins, fluoroquinolones, and aminoglycosides. Eleven (17%) patients were admitted to the Intensive Care Unit as a result of the LCBI. Thirteen deaths were recorded among the patients with LCBIs, with 6 (46%) associated with the HAI and 7 (54%) related to disease progression. Conclusions Our findings demonstrate that resistant pathogens were frequent among the LCBI isolates. Our preliminary results are guiding clinical management to be vigilant in our care of patients at high risk for bacteremia and poor clinical response by initiating more effective antimicrobials sooner. Importantly, reviewing reasons for antimicrobial resistance and implementing best antimicrobial use practices will protect our fragile antibiotic arsenal. Infection surveillance programs, such as ours, and other initiatives which promote infection prevention and control in POU will increase the quality of care for these vulnerable patients.


1948 ◽  
Vol s3-89 (7) ◽  
pp. 239-252
Author(s):  
P. B. MEDAWAR

The transplantation of skin from one rabbit to another elicits a reaction that conforms in main outline with that of an actively acquired immunity. The experiments described in this paper were designed to test the hypothesis that the regression of such grafts is secured by the action of antibodies demonstrable in vitro. Skin from adult rabbits has therefore been cultivated in the presence of serum and growing mesenchymal tissues derived solely from rabbits heavily and specifically immunized against it. Immune sera and tissues are without effect on the survival, cell-division frequency and migratory activities of explanted skin, and agglutinins for epidermal cell suspensions are not demonstrable in immune sera. With certain stated qualifications, it has therefore been concluded that the occurrence of free antibodies is not a sufficient explanation of the regression of skin homografts in vivo.


1998 ◽  
pp. 469-472
Author(s):  
S. Budimir ◽  
D. Stojičić ◽  
LJ. Ćulafić ◽  
R. Vujičić

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