Mysteriously, a Huge Study Finds a Drop in Antibiotic Resistant (MRSA) Infections
For once there is good news — surprising news, but good news — in the fight against antibiotic-resistant organisms. A recent study found that Staphylococcus aureus bacteria is becoming more sensitive to some key drugs used to treat it.
Helio S. Sader, Senior Director at JMI Laboratories, presented his findings on June 4 at the ASM Microbe conference in New Orleans, Louisiana.
Sader’s study examined nearly 20,000 Staphylococcus aureus infections in patients hospitalized in medical facilities in 30 states between 2009 and 2015. One of their key findings was that rates of Staphylococcus aureus infections that were resistant to methicillin treatment — a virulent and hard-to-treat infection called MRSA — decreased during that period.
“Results showed that S. aureus‘ rates of resistance to certain antibiotics decreased over time, which isn’t often seen,” Sader said in a press release.
MRSA is more deadly than other staph bacteria, party because it produces enzymes that enable it to invade and destroy host tissues and help it travel to other sites. Rampant MRSA infections can require limb amputations to prevent it from moving to other parts of the body.
The most common types of methicillin-resistant Staphylococcus aureus infections in the community are skin wounds, and occasionally, pneumonia. In healthcare settings, MRSA is more apt to invade the bloodstream, like at surgical sites, and bloodstream infections are the deadliest. Blood infections with MRSA are the deadliest — about 31% of those patients die.
The high death rate associated with MRSA bloodstream infections and its antibiotic resistance earned it a place on the Centers for Disease Control list of Serious Threats to global health.
Between 2009 and 2015, the researchers studied 19,036 Staphylococcus aureus infections in the US, half of which were skin infections, about 22% were respiratory infections, and 20% were bloodstream infections. The study found that in 2009, 47.2% of these infections were resistant to methicillin, but that rate dropped to 43.6% in 2015, then dropped again, to 42.2% in 2016.
In contrast, MRSA also became less resistant to another antibiotic, clindamycin, during the study period. It worked on 64.4% of the MRSA infections in…