Studies conducted in the past few years have shown that increase in the use of antibiotics has resulted in significant rise in antibiotic-resistant superbugs. Now, findings of a new study are suggesting that some antibiotics are not only failing to treat such infections but are also making patients sicker.

The said study was carried out by a research team at the Cedars-Sinai Medical Center in Los Angeles and particularly focused on the superbug called MRSA or methicillin-resistant Staphylococcus aureus. MRSA was in the news last month when Daniel Fells, a New York Giants footballer, got admitted to the hospital for getting treated for it.

The US Centers for Disease Control & Prevention (CDC) says that MRSA is primarily known to cause skin infections and a range of other infections. However, when it comes to patients in hospitals, the superbug can cause more severe health issues such as pneumonia, infections in surgical sites, bloodstream infections, etc.

It’s true that anybody can develop MRSA infection after sharing personal objects that have come in contact with an infected wound or after coming in direct contact with an infected wound. However, the risk of having the infection augments significantly for people in crowded places and places where skin-to-skin contact is common. Examples of individuals who are at greater risk of having MRSA infection are school kids, kids in daycare, athletes, patients in hospitals, army personnel residing in barracks, and so on.

Data offered by CDC from the year 2011 suggests that MRSA leads to more than 80,000 invasive infections and as many as 11,000 related deaths every year. The researchers said that these figures showed that MRSA is one of America’s most prominent antibiotic-resistant pathogens.

Researchers conducted this new study for investigating the factors that make the superbug so pathogenic. They said that although a number of previous studies have shown that diseases resulting from MRSA are more severe than common staph infections, the reasons behind the increased severity were never clear.

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During the study, they found that in mice treated with antibiotics known as beta-lactams (antibiotics boasting similar properties as methicillin) the MRSA bacteria resulted in the formation of inflammatory cell walls, which damage tissues. Beta-lactams are antibiotics that work by neutralizing enzymes responsible for making cell walls and thereby kill common staph.

However, during this new study it was found that one of the enzymes known as PBP2A doesn’t get neutralized by beta-lactams. In fact, PBP2A allows MRSA to keep on building the cell wall.