Increasing numbers of antibiotic-resistant Enterobacteriaceae are responsible of serious problems in infection control. This phenomenon also contributes to the global spread of carbapenemase- producing bacteria becoming therefore especially worrisome [23]. Indeed, it is a major public health concern, mainly within communities. Our study reported for the first time the occurrence of carbapenemase-producing E. coli in children with diarrhea in rural settings of Burkina Faso.
The isolated strains were mainly resistant to amoxicillin-clavulanic acid, amoxicillin, tetracycline, trimetoprim-sulfametoxazol, colistin-sulfate, piperacillin, cefotaxime, ceftriaxone, aztreonam, cefixime and cefepime (between 60% and 100%). Particularly, two E. coli harbored resistance patterns to imipenem. In contrast, no resistance to imipenem was observed in Salmonella strains. Similar results concerning E. coli resistance to imipenem were reported in India [12]. Susceptibility to netilmicin and ciprofloxacin appears to follow the general trend observed elsewhere in the world.
Our finding on overall prevalence of E. coli harboring carbapenemase genes in the 275 children was 1.81%. This result is similar to 2.5% reported in pets in Africa [3] suggesting that bacteria producing carbapenemase are currently spreading among these pets [3] and because of the proximity between humans and animals, these bacteria can contaminate humans. Indeed, animals could be reservoirs of gene transmission to humans. For example, it has been shown that poultry flocks contribute to the global dissemination of Salmonella Kentucky ST198-X1-SGI1CIP-R strain in developing countries [24]. Since subsistence, farming and animal husbandry are the primary economic activities for the local populations in Boromo and Gourcy, the spread of these bacteria poses serious health concerns.
Oatherwises, we detected no carbapenemase genes in Salmonella strains. This is expected because carbapenemase-producing Salmonella strains are rarely isolated. In contrast, resistance to carbapenems was observed in CIP-R Salmonella KentuckyX1-ST198-SGI1 isolates in which carbapenemases blaVIM − 2 and blaOXA − 48 have been detected [24].
Three main genes were detected in E. coli strains: Klebsiella pneumoniae carbapenemase (KPC), Verona integrin-encoded metallo-β-lactamase (VIM) and Imipenemase (IMP-2) with a rate of 40% each. To our best of knowledge, this is the first report of blaKPC gene in E. coli in Burkina Faso. However, KPC producers have been described, mostly from nosocomial K. pneumoniae isolates, and E. coli strains in Israel but also from other enterobacterial species [25]. As K. pneumoniae was identified extensively worldwide, a study suggested that it may have contributed to the spread of the blaKPC genes [26].
As far as the class B metallo-β-lactamases (MBLs) is concerned, our results corroborate the existing reports. Endemicity of VIM- and IMP-type enzymes has been reported in Greece, Taiwan and Japan [27, 8], although outbreaks and single reports of VIM and IMP producers have been shown in many other countries [27].
It has been shown that carbapenemases can hydrolyze almost all β-lactams, and are easily transferable among enterobacterial species [28]. These genes are found in multidrug-resistant isolates consistent with the result found in the present study [28]. Therefore, its spread in Enterobacteriaceae is a public health issue. For example, invasive infections by carbapenem-resistant strains have been found to be associated with high morbidity and mortality rates [29].
Otherwises, several risk factors of colonization and infection with carbapenemase-producing Enterobacteriaceae (CPE) including severe underlying illness, prolonged hospital stay, the presence of invasive medical devices, and antibiotic use have been shown. [30–33]. According to previous studies, CPE have been associated with adverse clinical and economic outcomes such as increased mortality, increased length of stay, setting up an effective therapy scheme, decreased functional status on discharge, and increased cost of health care [34–37]. Young children (those under one year old) were severely infected with carbapenem-resistant E. coli. This is a matter of public health issues because the emergence of MBL-producing bacteria greatly limits treatment options [38]. The most frequent MBLs reported to date belong to the VIM and IMP types and have been described extensively worldwide [39].
To conclude, infections by carbapenem-resistant bacteria are difficult to treat successfully. This study highlights the need for rapid identification of MBL-producing Gram-negative species both for appropriate treatment and for timely implementation of infection control measures. In developing countries like Burkina Faso, phenotypic methods may be useful for routine detection of carbapenemase production, particularly when PCR is not available.