Two new species of antibiotic-resistant bacteria have been discovered in the blood of patients in China.
Scientists discovered two patients were carrying unidentified species of Enterobacteriaceae that did not respond to penicillin or the cephalosporin group of antibiotics in the lab.
Enterobacteriaceae exist in the gut and are usually harmless, however, they can cause meningitis if they enter the blood or pneumonia if they get into the lungs.
The scientists worry the emergence of new species of antibiotic-resistant bacteria will make deadly infections harder to cure, with delays in treatment often leading to sepsis.
The scientists, from Sichuan University, Chengdu, were led by Dr Wenjing Wu, from the centre of infectious diseases.
The study comes amid growing fears of antibiotic resistance - driven by the unnecessary doling out of the drugs - which has turned once harmless bacteria into superbugs.
The World Health Organization has warned if nothing is done the world is heading for a 'post-antibiotic' era.
In the US alone, around 2million become infected with antibiotic-resistant bacteria every year, resulting in at least 23,000 deaths.
Pneumonia, tuberculosis, gonorrhoea and salmonellosis are among the growing number of infections that are becoming harder to treat.
