For humans, the superbug MRSA, or methicillin-resistant staphylococcus aureus, is one of the most terrifying creatures that share our Earth.

A bacterium that is resistant to most antibiotics, it is estimated to have contributed to the death of 5,000 Americans in 2013. Many more develop invasive infections that can lead to complications like losing  a limb.

Public health officials have been hunting for an effective treatment for decades but have mostly run into dead-ends.  Now, a study published in Nature Communications raises the possibility that a promising new weapon for MRSA may have been right under our noses: tamoxifen.

Tamoxifen is a popular breast cancer drug used for both prevention and treatment. In addition to its anti-estrogen role in fighting tumors in the breast area, scientists have noticed that it also creates what the study called "excessive or aberrant" production of what are known as neutrophil extracellular traps — which are on the front lines of the body's defense system against infection.

University of California-San Diego researchers put this ability to the test in mice. They gave the mice tamoxifen and then injected them with enough MRSA to kill them. They found that the drug boosted the animals' chances of survival by a third.

Researcher Victor Nizet told the San Diego Union-Tribune that the results are very preliminary as they have only been studied in a lab and that more testing is needed before making the jump to humans, but that he hopes the study "inspires clinical trials in patients with severe infections."

"We believe this is part of the larger need that we have in medicine to move to a more holistic approach to treating infections," Nizet said.

Scientists are also testing a handful of other unconventional approaches to fighting MRSA. Earlier this year, researchers reported that 1,100-year-old home remedy comprised of a bit of garlic, some onion or leek, copper, wine and oxgall (a florid name for cow’s bile) appeared to hold some promise in the lab.

Doctors hope that one day, these treatments could be used to stop infections like the one that New York Giants tight end Daniel Fells is battling in his foot and ankle. On Sunday, the Giants dedicated their game to their teammate. reported Sunday that Fells, who has spent more than 10 days in the hospital, is in danger of losing his foot. Fells sought help Oct. 2 after he came down with a 104-degree fever and had foot and ankle pain. He was reportedly moved to the intensive care unit after several surgeries.

The Centers for Disease Control and Prevention says that studies show that roughly one in three people carry staph in their nose without any issues, and that two in 100 people carry MRSA. While anyone can get an infection through contact with an infected wound or by sharing contaminated items, people in certain settings that involve crowding and skin-to-skin contact, such as day-care centers, hospitals or sports locker rooms, might be at higher risk.

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