Characterization and Prevalence of a New Porcine Calicivirus in Swine, United States

Real-time reverse transcription PCR revealed that new St-Valerien–like porcine caliciviruses are prevalent (2.6%–80%; 23.8% overall) in finisher pigs in North Carolina. One strain, NC-WGP93C, shares 89.3%–89.7% genomic nucleotide identity with Canadian strains. Whether these viruses cause disease in pigs or humans or are of food safety concern requires further investigation

Methicillin-resistant Staphylococcus aureus in pigs and farm workers on conventional and antibiotic-free swine farms in the USA.

Much uncertainty remains about the origin and public health implications of livestock-associated methicillin-resistant Staphylococcus aureus (LA-MRSA). This study aimed to investigate the occurrence and prevalence of MRSA in general and LA-MRSA in particular in pigs and farm workers in five states. We collected nasal swabs from pigs and farm workers at 45 swine herds (21 antibiotic-free herds; 24 conventional herds) in Illinois, Iowa, Minnesota, North Carolina and Ohio. MRSA was isolated from 50 of 1085 pigs (4.6%) and 31 of 148 (20.9%) of farm workers. MRSA-positive pigs and people were clustered in four conventional swine farms in Iowa and Illinois. Based on genotyping, spa type t034, a common livestock associated variant, was predominant among both human and swine isolates. These results confirm the presence of LA-MRSA in pigs and swine farm workers in the USA, but the prevalence found is relatively low compared with European studies

Distribution of <i>spa</i> types among human and swine isolates of MRSA.

*<p>Ridom <i>spa</i> type.</p>#<p><i>spa</i> types of ST398 lineage.</p

Demographic and occupational characteristics of participating workers from farms with MRSA-positive swine.

*<p>Not all categories sum to the column total because of missing data for some participants.</p>1<p>p-values are based on Fisher's exact test (for categorical data) or the Wilcoxon rank sum test (for continuous data).</p>2<p>Interquartile range (IQR), represented by the values of the 25^th and 75^th percentiles.</p