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Background The Sabin vaccine is used world-wide, and most children with food allergies receive it without incident. However, in the 2009 vaccination campaign conducted in Argentina, four children experienced immediate-type hypersensitivity reactions following vaccination. Objective We aimed to review the medical history of the affected children, study their allergic condition after the episodes and analyse the presence of allergenic vaccine components. Methods Patients were selected based on their immediate allergic reactions following vaccination. They were assessed for allergies to cow's milk and hen's egg. The presence of cow's milk proteins in the vaccine was tested by various immunoassays involving cow's milk- or α-lactalbumin-specific polyclonal rabbit antiserum and patient sera. Results All of the patients had a history of milk allergy, and no history or current evidence of egg hypersensitivity was found. Levels of cow's milk- and Sabin vaccine-specific IgE were increased, and the result of a skin prick test with cow's milk proteins or the Sabin vaccine was positive in each patient. In addition, an ELISA using specific rabbit antiserum detected α-lactalbumin in the Sabin vaccine. When α-lactalbumin was employed as a soluble inhibitor in a competitive ELISA, binding to vaccine-coated plates by cow's milk- or α-lactalbumin-specific rabbit antiserum or by patient serum containing IgE was inhibited. Conclusions We have demonstrated that these patients were allergic to cow's milk, and had circulating and mast cell-bound IgE antibodies specific to cow's milk proteins. We found that the Sabin vaccine contained α-lactalbumin, which may have been responsible for the reactions elicited following vaccination with the Sabin and dual viral vaccines in combination. [ABSTRACT FROM AUTHOR]

The aim of this study was to standardize a diagnosis procedure to detect Mycobacterium avium subsp. paratuberculosis (Map) DNA in raw cow milk samples under field conditions. A procedure that combines both immunomagnetic separation and IS900-PCR detection (IMS-IS1 PCR) was employed on milk samples from 265 lactating Holstein cows from Map infected and uninfected herds in Argentina. IMS-IS1 PCR results were analyzed and compared with those obtained from milk and fecal culture and serum ELISA. The extent of agreement between both tests was determined by the Kappa test. IMS-IS1 PCR showed a detection limit of 10(1) CFU of Map/mL of milk, when 50:50 mix of monoclonal and polyclonal antibodies were used to coat magnetic beads. All of the 118 samples from the Map uninfected herds were negative for the set of the tests. In Map infected herds, 80 out of 147 cows tested positive by milk IMS-IS1 PCR (55%), of which 2 (1.4%) were also positive by milk culture, 15 (10%) by fecal culture, and 20 (14%) by serum ELISA. Kappa statistics (95% CI) showed a slight agreement between the different tests (<0.20), and the proportions of agreement were ≤0.55. The IMS-IS1 PCR method detected Map in milk of the cows that were not positive in other techniques. This is the first report dealing with the application of IMS-IS1 PCR in the detection of Map in raw milk samples under field conditions in Argentina., (Copyright © 2016 Sociedade Brasileira de Microbiologia. Published by Elsevier Editora Ltda. All rights reserved.)