Washington, March 20 (IANS): More kids in the US are developing infections caused by a concerning type of antibiotic-resistant bacteria that is on the rise, an alarming study has claimed.

Still uncommon, the bacteria are increasingly found in children of all ages, especially those one-five years old, raising concerns about dwindling treatment options.

“These antibiotic-resistant bacteria have traditionally been found in health care settings but are increasingly being found in the community, in people who have not had a significant history of health care exposure,” explained Latania K. Logan of Rush University Medical Center in Chicago.

Researchers analysed resistance patterns in approximately 370,000 clinical isolates from pediatric patients - collected nationwide between 1999 and 2011.

They determined the prevalence of a resistant type of Gram-negative bacteria, Enterobacteriaceae, that produces a key enzyme - extended-spectrum beta-lactamase (ESBL).

The enzyme thwarts many strong antibiotics.

Another indicator of ESBL prevalence, susceptibility to third-generation cephalosporins - an important class of antibiotics used to treat many infections - was also measured.

ESBLs were found in children across the country of all ages, but slightly more than half of the isolates with this resistance were from those one-five years old.

Nearly three-quarters (74.4 percent) of these bacteria were resistant to multiple classes of antibiotics.

ESBL-producing bacteria can spread rapidly and have been linked to longer hospital stays, higher health care costs and increased mortality, the study noted.

In a 2013 report, the Centers for Disease Control and Prevention has called ESBLs a 'serious concern' and a significant threat to public health.

Additional drug development, keeping younger patients in mind, is needed, said the study published in the Journal of the Pediatric Infectious Diseases Society.