In addition to the news that a new, highly dangerous strain of E. coli is to blame for 18 deaths and over 1,600 sickened in Europe, today it was announced that a new and dangerous strain of methicillin-resistant Staphylococcus aureus (MRSA) has been found in cow’s milk and numerous human samples. As reported by Kate Kelland of Reuters London, this new MRSA strain was found by Cambridge University scientists while researching S. aureus, a pathogen known to be potentially deadly to dairy cows.
“To find the same new strain in both humans and cows is certainly worrying. However, pasteurization of milk will prevent any risk of infection via the food chain,” said Laura Garcia-Alvarez, who worked on Holmes’ team.
MRSA is estimated to kill 19,000 people each year in the United States — far more than HIV and AIDS — and a similar number in Europe.
The overuse and misuse of antibiotics in recent decades have fueled a rise in drug-resistant “superbug” infections such as MRSA and C-difficile.
Last year, scientists warned that a new so-called superbug from India known as New Delhi metallo-beta-lactamase (NDM-1) was rapidly spreading around the world.
This new MRSA strain, however, is not detectible by standard testing methods, making its presence even more concerning.
During this study, Holmes team found that the new MRSA strain was resistant to some drugs, like normal MRSA, but it was also impossible to identify using standard molecular tests. These tests work by detecting the presence of the gene which makes the bug resistant to methicillin, called the mecA gene.
When another team of researchers decoded all the genes in the bacteria’s DNA, they found that the new strain does have a mecA gene, it is only 60 percent similar to the “normal” MRSA mecA gene, meaning it can’t be detected with standard tests.