The Indian superbug NDM-1, which has a gene that encodes an enzyme conferring resistance to almost all known antibiotics, has been found in the USA in a household cat.
Pets with NDM-1 could be a dangerous vector of infection, since people have close contact with them. The finding was announced by Rajesh Nayak, a research scientist at the FDA’s National Center for Toxicological Research in Jefferson, Arkansas. The gene, blaNDM, was found in isolates of E. coli that they had received as part of a project to study bacterial samples from veterinary laboratories all over the USA.
NDM-1 was first identified in 2008 in Sweden, in a man of Indian origin who had gone home to India, was hospitalized, recovered and then was hospitalized once again in Sweden. The Klebsiella discovered in his urine was resistant to a vast number of drugs, including some last-resort category drugs known as carbapenems. It was susceptible to only two drugs, one old and toxic. The other was new, but not effective in all tissues of the patient’s body.
In 2009, bacteria containing the NDM-1 gene, traveling on plasmids that can easily move between organisms, were found in the UK. NDM-1 was first found in the USA in 2010, in three residents living in three different states.
Almost all of the patients had ties to India or Pakistan. Since then, research has shown that the organisms containing the gene weren’t confined to hospitals, but were circulating widely in New Delhi, India, through the water supply and other vectors of infection. NDM-1 has spread to over 12 countries so far.
The actual cat that has the NDM-1 is unknown, as veterinarians collected the samples whenever pets were not feeling well as part of the initial project. The samples were collected between 2008 and 2009, making the timing somewhat perplexing. It was collected at the same time as the earliest recognition of the resistance factor in Europe, nearly a year before it was detected in the US.