Women and UTI's: Give up meat or give up sex?

This report is from my favourite site, Science Daily. It seems the types of E.coli which cause more than 80% of all Urinary Tract Infections (UTI's) in women is found on chicken and other products which may be in your supermarket trolley. Worse still, they found that these are antibiotic resistant strains which appear thanks to the use of antibiotics in factory farming.

Retail Meat Linked to Urinary Tract Infections: Strong New Evidence

ScienceDaily (Jan. 20, 2010) — Chicken sold in supermarkets, restaurants and other outlets may place young women at risk of urinary tract infections (UTI), McGill researcher Amee Manges has discovered. Samples taken in the Montreal area between 2005 and 2007, in collaboration with the Public Health Agency of Canada and the University of Guelph, provide strong new evidence that Escherichia coli bacteria originating from these food sources can cause common urinary tract infections.

The research team is also investigating whether livestock may be passing antimicrobial-resistant bacteria on to humans. This is due to the use of antibiotics to treat or prevent disease in the animals and to enhance their growth, which may lead them to develop resistance to the medication. When animals are slaughtered and their meat is processed for sale, the meat can be contaminated with these bacteria.

Full article here.

The researchers took samples from Canadian women diagnosed with UTI's in two geographic regions, then collected samples from foods sold in supermarkets and restaurants in the same locales. They then analysed the DNA of bacteria found from all samples and compared the genotypes to see if there were food sources of E.coli linked to UTI infection.

They found 3 genotypes in two chicken samples and one honeydew melon dish which were identical to antibiotic resistant profiles causing UTI in the human population. The presence of a pathogen on fruit is attributed to cross contamination with meat or from an individual involved in producing the food, and is not regarded as coming from manure fertilisers (although it may perhaps be difficult to rule this out altogether). They also feel that pork and beef products may be promoting the spread of antibiotic resistant bacteria, but the principal focus of this study was on chicken products. They further believe that contamination from humans was unlikely, I imagine due to the hygiene standards imposed upon workers in the Canadian meat industry.

So why is this happening? For years now, it has been thought that the use of antibiotics to promote growth in factory farmed animals increases the incidence of resistant strains of pathogenic bacteria in humans. This is in line with a foundation of evolutionary theory: any organism with a genetic mutation which increases the likelihood that it will persist will contribute more offspring to the next generation as the other individuals die off before being able to do so. Hence, while antibiotics kill off E.coli in chickens, these antibiotic resistant strains arise by natural selection.

Incidentally, it is not eating the meat which causes the UTI. According to the McGill University press release, the bacteria spreads during sex. Anyway, eating the contaminated meat increases the likelihood of UTI infection as these antibiotic resistant strains will then be present in the lower GI tract, and may then "travel from the anus to the vagina and urethra during sex, which can lead to the infection."

They don't go into any specific details about whether the likelihood of infection is increased or decreased by particular sexual acts. Prudes.

Source: Vincent C, Boerlin P, Daignault D, Dozois CM, Dutil L, Galanakis C, et al. Food reservoir for Escherichia coli causing urinary tract infections. Emerg Infect Dis. 2010 Jan.

DOI: 10.3201/eid1601.091118

Available from http://www.cdc.gov/EID/content/16/1/88.htm