This is not about travelers hospitalized abroad, just travelers. Not surprisingly backpackers acquired twice as much infections than businessmen.

82% of the Swedish travelers who went to India returned home with ESBL; from Egypt 57%; from Thailand 37%; from Peru 36% ; from South Africa 27% ; from Tanzania 24% .

Foreign travel is a major risk factor for colonization with Escherichia coli producing CTX-M-type extended-spectrum beta-lactamases: a prospective study with Swedish volunteers.

Foreign travel has been suggested to be a risk factor for the acquisition of extended-spectrum beta-lactamase (ESBL)-producing Enterobacteriaceae. To our knowledge, this has not previously been demonstrated in a prospective study.

Healthy volunteers traveling outside Northern Europe were enrolled. Rectal swabs and data on potential travel-associated risk factors were collected before and after traveling. A total of 105 volunteers were enrolled. Four of them did not complete the study, and one participant carried ESBL-producing Escherichia coli before travel.

Twenty-four of 100 participants with negative pretravel samples were colonized with ESBL-producing Escherichia coli after the trip.

All strains produced CTX-M enzymes, mostly CTX-M-15, and some coproduced TEM or SHV enzymes. Coresistance to several antibiotic subclasses was common. Travel to India was associated with the highest risk for the acquisition of ESBLs (88%; n = 7). Gastroenteritis during the trip was an additional risk factor (P = 0.003). Five of 21 volunteers who completed the follow-up after 6 months had persistent colonization with ESBLs.

This is the first prospective study demonstrating that international travel is a major risk factor for colonization with ESBL-producing Enterobacteriaceae.

Considering the high acquisition rate of 24%, it is obvious that global efforts are needed to meet the emergence and spread of CTX-M enzymes and other antimicrobial resistances.

Antimicrob Agents Chemother. 2010 Sep;54(9):3564-8. Epub 2010 Jun 14.