New MRSA Strain Resistant To Vancomycin, Increasing Mortality Rates

Methicillin Resistant Staphylococcus aureus (MRSA) is a bacterium, which is resistant to methicillin and is known to cause skin, bloodstream and surgical wound infections and pneumonia.  Most cases of MRSA infections arise in hospital setups that are brimming with ill people and in neonatal wards that host babies with a very weak immune system.

As the name suggests, MRSA infection cannot be treated with methicillin-type antibiotics, as is the case wiA very high magnification scanning electron micrograph (SEM) of a strain of Staphylococcus aureus bacteria taken from a vancomycin intermediate resistant culture (VISA).th other bacteria belonging to the staphylococcus group. As a result, they are treated with a newer kind of potent antibiotic- vancomycin.  However, a new study conducted by experts from Henry Ford hospital has shown a new strain of MRSA that is immune to vancomycin as well, making it five times more fatal than other strains.

Study authors say that MRSA strain USA600 contains unique characteristics that may be the cause of high death rate. Nevertheless, whether other factors such as patient’s age, diseases or the spread of infection did contribute to the poor survival rates collectively or with other factors, is still being studied. The average age of patients with the USA600 strain was 64 and of those with other MRSA strains was 52.

MRSA strains are known to be resistant to many drugs, limiting treatment options for those infected with these bacteria. Vancomycin, which is actually a very potent antibiotic and usually used as a second line therapy, is the only medication that MRSA is susceptible to. Vancomycin is administered intravenously to treat MRSA. It is therefore a very serious concern that USA600 strain in this study was found to be more resistant to this potent antibiotic.

The findings of the study presented at the 47th annual meeting of the Infectious Diseases Society of America, revealed that 50 percent of the patients infected with the strain died within 30 days compared to 11 percent of patients infected with other MRSA strains.

Says Carol Moore, PharmD., a research investigator in Henry Ford’s Division of Infectious Diseases and lead author of the study, “In light of the potential for the spread of this virulent and resistant strain and its associated mortality, it is essential that more effort be directed to better understanding this strain to develop measures for managing it.”

Article by Snigdha Taduri for Biomed-ME