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The article discusses a study on the effect of para-JEM BLUE diagnostic reagent on Mycobacterium avium subspecies paratuberculosis (MAP), a major pathogen of cattle. MAP was inoculated into broth-based culture media and was evaluated through fecal samples with known MAP status. The study showed that when para-JEM BLUE was eliminated from the broth, false-positive instrument signals increased. It found that para-JEM BLUE led to growth retardation in certain MAP.

The article discusses a study on the differences among the methods for extracting Mycobacterium avium subspecies paratuberculosis DNA for polymerase chain reaction from broth-based culture systems. The methods used for extraction included MagMAX, DNeasy, and phenol-chloroform. Results showed the existence of bacterial DNA in 197 out of 304 samples tested using the MagMAX method.

Human-to-swine transmission of seasonal influenza viruses has led to sustained human-like influenza viruses circulating in the U.S. swine population. While some reverse zoonotic-origin viruses adapt and become enzootic in swine, nascent reverse zoonoses may result in virus detections that are difficult to classify as "swine-origin" or "human-origin" due to the genetic similarity of circulating viruses. This is the case for human-origin influenza A(H1N1) pandemic 2009 (pdm09) viruses detected in pigs following numerous reverse zoonosis events since the 2009 pandemic. We report the identification of two human infections with A(H1N1)pdm09 viruses originating from swine hosts and classify them as "swine-origin" variant influenza viruses based on phylogenetic analysis and sequence comparison methods. Phylogenetic analyses of viral genomes from two cases revealed these viruses were reassortants containing A(H1N1)pdm09 hemagglutinin (HA) and neuraminidase (NA) genes with genetic combinations derived from the triple reassortant internal gene cassette. Follow-up investigations determined that one individual had direct exposure to swine in the week preceding illness onset, while another did not report swine exposure. The swine-origin A(H1N1) variant cases were resolved by full genome sequence comparison of the variant viruses to swine influenza genomes. However, if reassortment does not result in the acquisition of swine-associated genes and swine virus genomic sequences are not available from the exposure source, future cases may not be discernible. We have developed a pipeline that performs maximum likelihood analyses, a k-mer-based set difference algorithm, and random forest algorithms to identify swine-associated sequences in the hemagglutinin gene to differentiate between human-origin and swine-origin A(H1N1)pdm09 viruses. [ABSTRACT FROM AUTHOR]