CTX-M-9 group extended-spectrum β-lactamases in neonatal stool isolates: emergence in India

Area of Science:

• Microbiology
• Genetics
• Public Health

Background:

• Extended-spectrum beta-lactamases (ESBLs) are enzymes that confer resistance to beta-lactam antibiotics.
• The CTX-M family of ESBLs is a significant global health concern, with various groups identified.
• Previous reports from India primarily focused on the CTX-M-1 group of ESBLs.

Observation:

• This study investigated ESBLs in Klebsiella pneumoniae and Escherichia coli from neonatal stool samples in India.
• CTX-M-14-like and CTX-M-27-like ESBLs, belonging to the CTX-M-9 group, were identified for the first time in these isolates.
• The genes encoding the CTX-M-9 group ESBLs were found on transferable plasmids.

Findings:

• A high prevalence (77%) of ESBL-producing K. pneumoniae or E. coli was detected in the neonatal stool samples.
• The blaCTX-M-15 gene, belonging to the CTX-M-1 group, was the predominant ESBL gene identified.
• The CTX-M-9 group ESBLs were detected in stool samples but did not appear to cause active infection in the neonates.

Implications:

• The emergence and transferability of CTX-M-9 group ESBLs in a vulnerable neonatal population is a significant public health finding.
• While not causing current infections, the presence of these novel ESBLs may indicate a potential for future outbreaks or infections.
• This highlights the need for enhanced surveillance of ESBLs, particularly novel groups, in healthcare settings and the community in India.