A gene resistant to antibiotics of last resort is believed to be circulating in Cambodia, according to researchers in the Netherlands who have documented a troubling spread of the gene across three continents.

The MCR-1 gene, known to be common among farm animals in China, gives bacteria that carry it resistance to particular antibiotics, including Colistin, which is used to cure highly resistant infections.

Findings published this month by a team from the Academic Medical Centre, Amsterdam, suggest that the MCR-1 gene is also present in gut bacteria in the Kingdom, creating a greater risk of drug resistance among the population.

“When you have a lot of people carrying this bacteria, at a population level it may be increasingly difficult to treat specific infections,” says Constance Schultsz, who conducted the study of E coli bacteria from Dutch travellers who had visited Southeast Asia.

“What is worrisome is that it was found in perfectly healthy people, so it is remarkable how easily it can be acquired,” she said, adding that the notable resistance of bacteria found in Cambodia may be linked to the country’s high rates of antibiotic usage.

Colistin, which can be used to treat anything from urinary tract infections to septicaemia, was considered outmoded for decades, but has regained currency as newer antibiotics have been made redundant by resistance. In 2012, it was declared critically important for human medicine by the WHO, despite being rarely used.

“It is difficult to prescribe and hard to find here,” explained Eng Lengsea, head of the microbiology laboratory at Phnom Penh’s Calmette Hospital, who has been monitoring antibiotic resistance for more than five years.

“And this is a good thing, because if it is more available on the market, people will become more resistant.”

The WHO was not available for comment yesterday, but has previously acknowledged antibiotic resistance as a major public health concern in Cambodia.