Adults middle-aged or older who carry methicillin-resistant Staphylococcus aureus (MRSA) ‘superbug’ on their skin are twice as likely to die within the next decade as people who do not, according to a study by the University of Florida (UF).
“Very few people who carry MRSA know they have it, yet we have found a distinct link between people with undetected MRSA and premature death,” said lead author Arch Mainous, PhD, a professor in the department of health services research, management and policy at UF.
The findings suggest that routine screening for undetected MRSA may be warranted in older people to prevent deaths from infection.
A third of Americans carry Staphylococcus aureus, or staph, on their skin or in nasal passages, and of these about 1% carry MRSA, the notorious antibiotic resistant staph strain.
MRSA carriers may not even be aware that they carry the bacteria unless they develop an infection or are tested for it. A quarter of people who carry MRSA without an active infection, known as colonised MRSA for at least a year, eventually develop a MRSA infection.
“MRSA can be part of normal body flora, but it can lead to infection when immune systems are compromised, especially in people who are hospitalized, have underlying disease, or after antibiotic use,” said Prof Mainous, also vice chair for research in the UF College of Medicine’s department of community health and family medicine.
According to a 2017 Centers for Disease Control and Prevention report, 119 000 Americans experienced a staph bloodstream infection and nearly 20 000 died. Hospitalised patients with colonised MRSA may be particularly vulnerable to infection in hospital or after discharge. Among carriers, wounds, surgical incisions and use of medical devices, such as catheters, may also lead to MRSA infection.
In this study, researchers analysed data from the 2001-2004 National Health and Nutrition Examination Survey, a nationally representative study combining survey questions with laboratory testing, which includes nasal swabs for detecting MRSA.
Adjusting for risk factors including gender and ethnicity, the researchers linked data on participants ages 40-85 with data from the National Death Index to track deaths over an 11-year period.
The mortality rate among participants without MRSA was about 18% compared with 36% among those with colonised MRSA. There was no increased mortality risk for those with non-MRSA staph bacteria on their skin.
Although some states and hospital systems require MRSA testing for patients before hospital admission, policies for testing and treatment of colonised MRSA, which may include antibiotics use, vary widely betweens hospitals, Prof Mainous said.
“Without a uniform strategy, we are missing an opportunity to help prevent deaths caused by MRSA,” he said. “Maybe we should know who is carrying MRSA.”
Source: Medical-News.Net
Journal information: Mainous, A. G., et al. (2021) Methicillin-Resistant Staphylococcus Aureus Colonization and Mortality Risk Among Community Adults Aged 40-85. Journal of the American Board of Family Medicine.
