allele median (min-max) di erence at node 0-16 alleles di erent U.S. patient isolate U.S. salad isolate Canadian patient isolate Canadian salad isolate FIGURE. Phylogenetic tree by whole-genome multilocus sequence typing (wgMLST) of Listeria monocytogenes isolates* from patients and salad products with indistinguishable pulsed-field gel electrophoresis patterns-United States and Canada, † July 5, 2015-January 31, 2016 * By wgMLST, clinical and food isolates from the United States and Canada were closely related because they differed by a median of three alleles, with a range of 0-16 alleles. † 19 patients from nine U.S. states and six patients from Canada.

Salmonella is a leading cause of bacterial foodborne illness. We report the collaborative investigative efforts of US and Canadian public health officials during the 2013-2014 international outbreak of multiple Salmonella serotype infections linked to sprouted chia seed powder. The investigation included open-ended interviews of ill persons, traceback, product testing, facility inspections, and trace forward. Ninety-four persons infected with outbreak strains from 16 states and four provinces were identified; 21% were hospitalized and none died. Fifty-four (96%) of 56 persons who consumed chia seed powder, reported 13 different brands that traced back to a single Canadian firm, distributed by four US and eight Canadian companies. Laboratory testing yielded outbreak strains from leftover and intact product. Contaminated product was recalled. Although chia seed powder is a novel outbreak vehicle, sprouted seeds are recognized as an important cause of foodborne illness; firms should follow available guidance to reduce the risk of bacterial contamination during sprouting.

The scoliosis-screening program utilizes a referral pathway based on the radiologist's Risser stage interpretation in conjunction with the Cobb angle. The radiologist and the orthopaedic surgeons demonstrated only moderate agreement in their interpretations of Risser stages, resulting in a possible 21% over-referral rate. This study questions the efficacy of using the Risser stage as part of a large metropolitan scoliosis screening program and warrants further investigation.

On April 27, 2015, the Whatcom County Health Department (WCHD) in Bellingham, Washington, was notified by a local laboratory regarding three children with presumptive Escherichia coli O157 infection. WCHD interviewed the parents, who indicated that all three children had attended a dairy education event held in a barn April 20–24, 2015, during a school field trip. WCHD, the Washington State Department of Health, and CDC investigated to determine the magnitude of the outbreak, identify risk factors and potential environmental sources of infection, and develop recommendations. A total of 60 cases (25 confirmed and 35 probable) were identified, and 11 patients were hospitalized.

No abstract