Intestinal colonisation with carbapenemase producing enterobacteriaceae after foreign travel

Bacteria from clinical and non-clinical settings are becoming increasingly
resistant to conventional antibiotics. Multidrug-resistant Gram-negative
bacteria pose the greatest risk to public health. Not only is the increase in
resistance of Gram- negative bacteria faster than in Gram-positive bacteria,
but also there are fewer new and developmental antibiotics active against
Gram-negative bacteria and drug development programmes seem insufficient to
provide therapeutic cover in 10-20 years [Lancet Infect Dis. 2010 September ;
10(9): 597-602].

The increase in resistance of Gram-negative bacteria is mainly due to mobile
genes on plasmids that can readily spread through bacterial populations.
Unprecedented human air travel and migration allow these bacterial plasmids and
clones to be transported rapidly between countries and continents. Much of this
dissemination is undetected, with resistant clones carried in the normal human
flora and only becoming evident when they are the source of endogenous
infections.

Foreign travel has been demonstrated to be a risk factor for colonization with
ESBL-producing Enterobacteriaceae [Antimicrobial Agents and Chemotherapy, Vol
54, Sept. 2010, p. 3564-3568]. Travel to areas with a higher prevalence of
strains producing ESBLs was a risk factor for the acquisition of ESBL-producing
bacteria. Recently a new type of carbapenem resistance gene, designated
blaNDM-1 was found in a patient, repatriated to Sweden after admission to
hospital in New Delhi, India.

Enterobacteriaceae with NDM-1 carbapenemases are highly resistant to many
antibiotic classes and potentially herald the end of treatment with ß-lactams,
fluoroquinolones, and aminoglycosides*the main antibiotic classes for the
treatment of Gram-negative infections. Only a few isolates remain sensitive to
individual aminoglycosides and aztreonam, perhaps owing to the loss of
resistance genes (eg, those encoding aminoglycoside modifying enzymes, 16S rRNA
methylases, or blaCMY-4). However, most isolates are only susceptible to
colistin and tigecycline.

Primary Objective:
The primary objective of our study was to prospectively study the fecal
acquisition of NDM-1 carbapenemases producing Enterobacteriaceae during foreign
travel and the persistence rate of acquired NDM-1 carbapenemases producing
isolates after 6 months. If we know the risk of acquisition
during travel we can decide to screen patients for ESBL and NDM carriage when
they have travelled and are admitted to the hospital.



Secondary Objective(s):
Our secondary objective was to assess potential travel- associated risk factors
for the acquisition of NDM-1 carbapenemases, such as destination,
gastroenteritis, and antibiotic use during travel

Prospective cohort study at the Travel clinic of the department of Infectious
Diseases, Leiden University Medical Centre during March and June 2011

Not applicable