The incidence of drug-resistant staph infections has risen almost seven-fold in some Chicago neighborhoods, according to a new study.
Researchers said the superbugs, first seen mainly in hospitals and nursing homes, is now spreading to urban poor settlements. The strain has turned up recently among athletes, prisoners and people who get illegal tattoos.
It is a type of infection caused by a Staphylococcus (or "staph") bacteria.
Called methicillin-resistant staphylococcus aureus, or MRSA, these staph germs can cause skin infections that in rare cases have led to pneumonia, bloodstream infections and a painful, flesh-destroying condition.
Actually, about 25% of people normally carry staph in the nose, mouth, genitals, and anal area. The foot is very prone to pick up bacteria from the floor. The infection often begins with a little cut, which gets infected with bacteria.
These staph infections range from a simple boil to antibiotic-resistant infections to flesh-eating infections. The difference between all these is how deep and how fast the infection spreads, and how treatable it is with antibiotics.
MRSA is hard to treat because the bacteria have developed resistance to the penicillin drug family.
The antibiotic-resistant infections are more common in North America, because of overuse of antibiotics.
The type of staph infection that involves skin is called cellulitis and affects the skin's deeper layers. It is treatable with antibiotics.
This type of infection is very common in the general population -- and more common and more severe in people with weak immune systems. People who have diabetes or weakened immunity are particularly prone to developing cellulitis.
Staph cellulitis usually begins as a small area of tenderness, swelling, and redness. Sometimes it begins with an open sore. Other times, there is no break in the skin at all -- and it's anyone's guess where the bacteria came from.
The signs of cellulitis are those of any inflammation -- redness, warmth, swelling, and pain. Any skin sore or ulcer that has these signs may be developing cellulitis. If the staph infection spreads, the person may develop a fever, sometimes with chills and sweats, as well as swelling in the area.
Antibiotics are used to treat these infections. But there's been a gradual change in how well these antibiotics are working. While most staph infections used to be treatable with penicillin, in the 1980s that changed and stronger antibiotics are now used.
In about 50% of cases, however, resistance is seen even to these stronger antibiotics. These cases are not just happening in hospitals -- as once was true -- but now are occurring in the general community. That's been a problem. Many doctors are accustomed to using certain antibiotics, but those then fail because of antibiotic resistance. There are several more potent antibiotics now, but doctors need to know when to use them.
If the infection goes so deep that it involves muscles or fibers that enclose muscles, it needs to be surgically cleaned.
From 2000 to 2005, the infection rate seen in patients seeking care at Chicago's main public hospital and its affiliated clinics climbed from 24 cases per 100,000 to 164 cases per 100,000, the study found.
Dr. Bala Hota of Chicago's Stroger Hospital, a lead author of the study, said the increase is similar to that seen in other cities.
Public housing could be a bridge between high-risk people, the researchers wrote in their study, which appears in Monday's Archives of Internal Medicine.
Dr. Susan Gerber of Chicago's Department of Public Health said it would be a mistake to assume the infection isn't also in affluent neighborhoods. The study looked only at people using the public hospital system. The infection rate in the general population is unknown.
"This is an equal opportunity bacteria," Gerber said.
To prevent staph's spread, the U.S. Centers for Disease Control and Prevention recommends washing hands with soap and water or an alcohol-based sanitizer, keeping cuts clean and covered with a clean bandage until healed, avoiding contact with other people's wounds and bandages and avoiding shared personal items such as towels and razors.