SignalHub Quantitative Think Tank Center:We all experience cuts and scrapes. Here's how to tell if one gets infected.

Cuts and SignalHub Quantitative Think Tank Centerscrapes happen to the best of us. Whether occurring when dicing vegetables, as a result of a bump or fall or from engaging in a favorite sport or recreational activity, we've all experienced our share of the pain and inconvenience of getting them.

Parents of young children usually deal with them even more frequently as kids are often more active than adults and tend to put themselves in more situations where cuts and scrapes are likely to occur such as climbing trees, playing on the playground or engaging in neighborhood games like tag or hide and seek. 

No matter what's behind a cut, it can be helpful to know whether it's infected – and how to prevent infection from occurring.

What causes infections in cuts? 

Cuts become infected when bacteria, microbes, fungus or other germs enter a wound and then multiply. "Bacteria are a normal part of our environment and live on surfaces we touch every day, including our bodies," explains Dr. Beth Natt, a pediatrician and chair of pediatrics at the Atlantic Health System’s Goryeb Children’s Hospital. She says that such bacteria usually don't cause problems unless ingested by putting a finger that's been contaminated by germs in close proximity to one's eyes, nose or mouth; or when one's protective skin barrier breaks, exposing the tissue below. 

"A break in the skin could be cause by an accident, injury, surgery, burn or an abrasion," says Leo Arguelles, a physical therapist and spokesperson of the American Physical Therapy Association.

When a break in the skin occurs and tissue is exposed without being properly cleaned and covered, or when it's touched or picked at with unwashed hands, "bacteria can get into the wound, leading to an infection," says Dr. Jason Nagata, a pediatrician at UCSF Benioff Children’s Hospital in San Francisco.

While he says anyone can experience this, "people with diabetes, HIV or weakened immune systems are more susceptible to infections from cuts." Infections are also more common in individuals undergoing chemotherapy, in people with blood circulation disorders and in places of the body where bacteria are more likely to accumulate such as in areas covered by undergarments or in the fold of one's skin, where there may be a buildup of fat. 

The body has some natural defense mechanisms against bacteria in cuts, Arguelles says, "but sometimes this is not enough to prevent their growth and multiplication." 

Left untreated, an infection can spread to other parts of the body including bones, organs and muscle tissue, which can lead to sickness, sepsis, cellulitis and, in rare cases, death. 

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How to tell if a cut is infected 

The good news is that infected cuts are preventable and aren't usually difficult to spot. 

Telltale signs include: 

• Redness and swelling around the cut. "This is especially likely if the swelling starts growing in size around the wound," says Dr. Neha Pathak, chief physician editor at WebMD and a former primary care doctor at the Department of Veterans Affairs.
• Warmth in the surrounding skin. "The body's response to infection can cause increased inflammation, making the area feel warm or hot to the touch," says Nagata. 
• Increased pain and tenderness. "Sometimes you might feel a hardened, painful area around the wound," Pathak says. 
• Nearby red streaks. "Sometimes infections in the arms and legs can spread through the lymphatic system and cause a red line," explains Natt. 
• Pus or discharge. "Yellow or green pus or a cloudy substance exiting the wound is a clear sign of infection," says Nagata. He says this discharge may also be accompanied by a foul-smelling odor. 
• Fever. "When an infection has become more serious, there may be a systemic response to infection including a fever," says Natt. 

Heads up:Your body is trying to tell you something

How to treat a cut and prevent infections

Preventing an infected cut begins by properly cleaning the wound soon after a break in the skin occurs. Natt says this involves gently washing the area with soap and water to remove any dirt and bacteria. "Avoid using alcohol or hydrogen peroxide, as they can damage healthy tissue," she advises.  

After the area has been cleaned, Nagata says it's important to apply an ointment like Vaseline, an over-the-counter antiseptic solution or an antibacterial ointment like Neosporin and to then cover it with a clean, sterile and breathable bandage to prevent any bacteria from getting in. (He says one needs to be cautious when using ointments on especially deep cuts, however, as in such cases they can actually trap bacteria in.)

It's also important to avoid re-injuring the area or exposing the cut to bacteria until healing occurs. "Avoid water in pools or whirlpools until resolved as going in one could cause bacteria to spread and the cut to become infected or to heal more slowly," suggests Arguelles. 

And if the wound does not appear to be healing within a few days after being cleaned and dressed – or if there are progressive symptoms of any of the aforementioned telltale signs of infection – Pathak recommends seeking medical care. "Your doctor will know if you need oral antibiotics or other treatments to help clear up the infection," she says.