Cattle be shedding STECs

Shiga toxin-producing Escherichia coli (STEC) is an important foodborne pathogen that can cause hemorrhagic colitis and hemolytic-uremic syndrome. Cattle are the primary reservoir for STEC, and food or water contaminated with cattle feces is the most common source of infections in humans.

beef.cattleConsequently, we conducted a cross-sectional study of 1,096 cattle in six dairy herds (n = 718 animals) and five beef herds (n = 378 animals) in the summers of 2011 and 2012 to identify epidemiological factors associated with shedding.

Fecal samples were obtained from each animal and cultured for STEC. Multivariate analyses were performed to identify risk factors associated with STEC positivity. The prevalence of STEC was higher in beef cattle (21%) than dairy cattle (13%) (odds ratio [OR], 1.76; 95% confidence interval [CI], 1.25, 2.47), with considerable variation occurring across herds (range, 6% to 54%). Dairy cattle were significantly more likely to shed STEC when the average temperature was >28.9°C 1 to 5 days prior to sampling (OR, 2.5; 95% CI, 1.25, 4.91), during their first lactation (OR, 1.8; 95% CI, 1.1, 2.8), and when they were <30 days in milk (OR, 3.9; 95% CI, 2.1, 7.2). These data suggest that the stress or the negative energy balance associated with lactation may result in increased STEC shedding frequencies in Michigan during the warm summer months.

Future prevention strategies aimed at reducing stress during lactation or isolating high-risk animals could be implemented to reduce herd-level shedding levels and avoid transmission of STEC to susceptible animals and people.

STEC shedding frequencies vary considerably across cattle herds in Michigan, and the shedding frequency of strains belonging to non-O157 serotypes far exceeds the shedding frequency of O157 strains, which is congruent with human infections in the state. Dairy cattle sampled at higher temperatures, in their first lactation, and early in the milk production stage were significantly more likely to shed STEC, which could be due to stress or a negative energy balance. Future studies should focus on the isolation of high-risk animals to decrease herd shedding levels and the potential for contamination of the food supply.

Factors associated with Shiga toxin-producing Escherichia coli shedding by dairy and beef cattle

Cristina Venegas-Vargasa*, Scott Hendersona,b, Akanksha Khareb*,Rebekah E. Moscib, Jonathan D. Lehnertb*, Pallavi Singhb,Lindsey M. Ouelletteb*, Bo Norbya, Julie A. Funka, Steven Rustc, Paul C. Bartletta,Daniel Groomsa and Shannon D. Manningb

aDepartment of Large Animal Clinical Sciences, College of Veterinary Medicine, Michigan State University, East Lansing, Michigan, USA

bDepartment of Microbiology and Molecular Genetics, Michigan State University, East Lansing, Michigan, USA

cDepartment of Animal Science, Michigan State University, East Lansing, Michigan, USA

Applied and Environmental Microbiology, August 2016, Volume 82, Number 16, Pages 5049-5056, doi:10.1128/AEM.00829-16

Check the water: E. coli O157 in UK cattle

A longitudinal study in England and Wales of two dairy, five beef-fattener and three beef-suckler herds was carried out to identify risk factors for young cattle excreting verocytotoxin-producing Escherichia coli O157 (VTEC O157).


A total of 1,383 cattle, selected into cohorts at 0–24 months were sampled between March 2000 and February 2001. Mixed-effects logistic regression was employed to identify significant associations between VTEC O157 isolation from rectal faecal samples and explanatory factors (P < 0·001 unless shown).

The results revealed a positive association with feeding root crops and a negative association with animals fed silage, milk (P = 0·001) or grain (P = 0·027). Cattle in suckler herds (P = 0·001) and those changing group between sampling visits were identified as negatively associated with VTEC O157 presence. The recovery of VTEC O157 varied throughout the year. However, the winter period from December to February was a risk factor in the multivariable analysis.

Cattle in pens were 4·7 times more likely to shed VTEC O157 than those group-housed or at pasture. VTEC O157 detected in pooled environmental faecal pats and biofilm of the water supply within a group’s enclosure were positively associated with an animal’s VTEC O157 status in the multivariable logistic regression, as was detection of VTEC O157 in the pooled faecal pats at the previous visit.

A longitudinal study of risk factors for shedding of VTEC O157 by young cattle in herds with known E. coli O157 carriage

Epidemiology and Infection / Volume 144 / Issue 09 / July 2016, pp 1818-1829Copyright © Cambridge University Press 2016  DOI: (About DOI), Published online: 01 February 2016

P. Smith, W. J. Pollitt And G. A. Paiba

Michigan Tough Mudder race organizers share info about avoiding illnesses

Over the past 6 months I’ve been running a few times a week as a way to get some decent exercise while I try to get to a more healthy weight.

Not an activity that I liked until I was about 30, I do most of my running on treadmills while I watch sports and listen to podcasts. There are a few guys on my hockey team who have taken up endurance mud running as a way to work off the chicken sandwiches and beer we consume every Monday night. A couple of them ran the Tough Mudder in South Carolina a couple of years ago and are trying to talk me into joining them in the spring. Not sure I’m into it.TMSplash

From the organizer’s website, “Tough Mudder events are hardcore 10-12 mile obstacle courses designed by British Special Forces to test your all around strength, stamina, mental grit, and camaraderie. Triathlons, marathons, and other lame-ass mud runs are more stressful than fun. Not Tough Mudder. As hardcore as our courses are, we meet you at the finish line with a beer, a laugh, and a rockin’ live band.”

The site lists a set of obstacles with names like Arctic Enema, Dirty Ballerina and Kiss of Mud.

The races have a history of testing more than physical and mental toughness – they have been linked to multiple pathogen outbreaks.

A 2012 Tough Mudder in Scotland was linked to at least three cases of E. coli O157.  Last year a Michigan event recent was linked to norovirus.

According to Mlive, the organizers of this weekend’s Michigan event are addressing pathogen concerns.

Tough Mudder officials want to remind anyone planning to compete or attend this year’s event to practice good hygiene before and after attending.

“Illnesses of this nature are extremely rare. More than 1.5 million Mudders have run a Tough Mudder course; this issue is highly isolated,” said Ben Johnson, a spokesperson for Tough Mudder, via email. “However, safety is our No. 1 priority, and we encourage all participants, spectators, and volunteers to take the following preventative measures:

– It is important to not attend the event if you are feeling ill. We can provide a transfer to a future event.

– Practice good hygiene before and after the event:

Stay home for at least 48 hours after symptoms disappear.

Use chlorine-bleach based household cleaners to disinfect contaminated surfaces.

Free transfers to a future event is a good step – maybe that will result in sick folks skipping it until they’re done shedding pathogens.

Fecal shedding of non-O157 serogroups of shiga toxin–producing Escherichia coli in feedlot cattle vaccinated with an Escherichia coli O157:H7 SRP vaccine or fed a lactobacillus-based direct-fed microbial

The objectives of this study were to determine whether fecal shedding of non-O157 Shiga toxin–producing Escherichia coli (STEC) in feedlot cattle was affected by the use of an E. coli O157:H7 vaccine or a direct-fed microbial (DFM) and whether the shedding of a particular non-O157 STEC serogroup within feces was associated with shedding of O157 or other non-O157 STEC serogroups. A total of 17,148 cattle in 40 pens were cow.poop.spinachrandomized to receive one, both, or neither (control) of the two interventions: a vaccine based on the siderophore receptor and porin proteins (E. coli SRP vaccine, two doses) and a DFM product (low-dose Bovamine). Fresh fecal samples (30 samples per pen) were collected weekly from pen floors for four consecutive weeks beginning approximately 56 days after study allocation. DNA extracted from enriched samples was tested for STEC O157 and non-O157 serogroups O26, O45, O103, O111, O121, and O145 and for four major virulence genes (stx 1, stx 2, eae, and ehxA) using an 11-gene multiplex PCR assay. Generalized linear mixed models were used to analyze the effects of treatments and make within-sample comparisons of the presence of O-serogroup–specific genes. Results of cumulative prevalence measures indicated that O157 (14.6%), O26 (10.5%), and O103 (10.3%) were the most prevalent STEC O serogroups. However, the vaccine, DFM, or both had no significant effect (P > 0.05) on fecal prevalence of the six non-O157 STEC serogroups in feedlot cattle. Within-sample comparisons of the presence of STEC serogroup–specific genes indicated that fecal shedding of E. coli O157 in cattle was associated with an increased probability (P < 0.05) of fecal shedding of STEC O26, O45, O103, and O121. Our study revealed that neither the E. coli O157:H7 vaccine, which reduced STEC O157 fecal shedding, nor the DFM significantly affected fecal shedding of non-O157 STEC serogroups, despite the fact that the most prevalent non-O157 STEC serogroups tended to occur concurrently with O157 STEC strains within fecal samples.

Journal of Food Protection®, Number 5, May 2014, pp. 696-863 , pp. 732-737(6)

Cernicchiaro, N.1; Renter, D. G.2; Cull, C. A.1; Paddock, Z. D.1; Shi, X.1; Nagaraja, T. G.1