Phages be sexing up E. coli O157 in England and Wales

We used whole-genome sequencing to investigate the evolutionary context of an emerging highly pathogenic strain of Shiga toxin–producing Escherichia coli (STEC) O157:H7 in England and Wales. A timed phylogeny of sublineage IIb revealed that the emerging clone evolved from a STEC O157:H7 stx-negative ancestor ≈10 years ago after acquisition of a bacteriophage encoding Shiga toxin (stx) 2a, which in turn had evolved from a stx2c progenitor ≈20 years ago. Infection with the stx2a clone was a significant risk factor for bloody diarrhea (OR 4.61, 95% CI 2.24–9.48; p<0.001), compared with infection with other strains within sublineage IIb. Clinical symptoms of cases infected with sublineage IIb stx2c and stx-negative clones were comparable, despite the loss of stx2c. Our analysis highlighted the highly dynamic nature of STEC O157:H7 Stx-encoding bacteriophages and revealed the evolutionary history of a highly pathogenic clone emerging within sublineage IIb, a sublineage not previously associated with severe clinical symptoms.

Highly pathogenic clone of shiga toxin-producing Escherichia coli O157:H7, England and Wales, December 2018

Emerging Infectious Diseases vol. 24 no. 12

Lisa Byrne, Timothy Dallman, Natalie Adams, Amy Mikhail, Noel McCarthy, and Claire Jenkins

Age of Aquarius: Trade, food safety, always intertwined

I don’t like year-end reviews.

It’s an artificial creation and food safety happens day-in-day-out.

Sure I’ll engage in some sacrifice on the winter solstice (if Chapman is dumb enough to be around) and dance naked under the setting sun of the summer solstice, but that’s it.

However The Packer’s most-viewed stories list of 2012 seemed particularly apt.

Food safety is about trade. That’s why the Mexico/Florida tomato war was the #1 most viewed story.

But #2-4 were actually about food safety:

• cantaloupe outbreak shakes up industry, leading to California’s new certification push;

• tainted mangoes cause widespread illness; and,

• sprout illnesses force national chains into menu changes and two new alliances.

Good food safety is good business. Apparently it’s a new revelation.