Normally associated with hospital environments, a community based resistant superbug that causes a deadly staph infection is posing a growing danger to healthy people, especially children, across the US. Called CA-MRSA (short for Community Acquired-Methicillin-Resistant Staphylococcus aureus), the bacterium is said to be more virulent than the hospital acquired strain.

MRSA is resistant to methicillin and other common antibiotics such as oxacillin, penicillin and amoxicillin and occurs most frequently in hospitals, nursing homes and other health care facilities (for instance dialysis centres) where patients tend to have weakened immune systems.

CA-MRSA on the other hand is acquired outside of these environments, in the community, by otherwise healthy people who have not (within the last 12 months) been hospitalized or had a medical procedure such as surgery, dialysis or had a catheter inserted. CA-MRSA usually manifests as skin infections like pimples and boils.

Director of Pediatric Infectious Diseases at Driscoll Children’s Hospital in Corpus Christi, Texas, Dr Jaime Fergie who has been studying MRSA and CA-MRSA for over 10 years said in a press release that:

“We’ve seen that MRSA working in the community is much more virulent.”

South Texas was one of the first regions in the US to report CA-MRSA. In 2004 Fergie published a study with a colleague Dr Kevin Purcell that said the rise in infections grew from 5 per 10,000 patients in 1999 to 360 per 10,000 in 2004.

Infection routes for staph and all forms of MRSA is primarily via hands which become contaminated through contact with: people who are already infected or colonized with the bacteria; touching infected body sites; or touching equipment or surfaces that have been contaminated by body fluids carrying the bacteria. Skin to skin contact, crowds and poor hygiene have also been cited as infection routes, according to the Centers for Disease Control and Prevention (CDC).

According to a statement from Driscoll Children’s Hospital, most children infected with CA-MRSA present with skin and soft tissue infection, but some have developed more severe symptoms and a few have died.

The severely infected children have had to undergo multiple surgery, including orthopedic, cardiothoracic, and drainage procedures, they said.

Called “community staph”, CA-MRSA bacteria enter the body through open wounds on the skin, emerge as a boil or abscess that can look like a bite from a spider. The bacteria can get into the bloodstream, bones, joints, muscles and lungs.

Fergie said CA-MRSA can be prevented by “diligent hand washing and good hygiene”. He said parents should know what the symptoms are to make sure their children are diagnosed and treated early.

Incarceration has also been identified as a major risk factor for CA-MRSA. A study published in the September issue of Nature Reviews Microbiology by biomathematicians at the Semel Institute for Neuroscience and Human Behavior at the University of California, Los Angeles (UCLA), led by professor Sally Blower, reported how a computer model was used to predict the severity and potential consequences of an outbreak in a jail.

Outbreaks of CA-MRSA occur frequently in jails around the US. For instance, the Los Angeles County Jail has a high rate of CA-MRSA, and outbreaks have been reported on a regular basis since 2002, totalling some 8,500 cases. Once they are released, inmates spread the bacteria to the rest of the community, said Blower.

According to the CDC, the best way to prevent staph or MRSA skin infections is to practise good hygiene such as:

  • Keep your hands clean by washing thoroughly with soap and water or an alcohol based sanitizer.
  • Clean and cover cuts and scrapes until healed.
  • Don’t touch other people’s wounds or bandages.
  • Don’t share personal items such as towels and razors.

Click here for more information on CA-MRSA (CDC).

Written by: Catharine Paddock