What are the main causes of blood poisoning?

Blood poisoning (sepsis) occurs when bacteria causing infection in another part of your body enter your bloodstream. The presence of bacteria in the blood is referred to as bacteremia or septicemia. The terms “septicemia” and “sepsis” are often used interchangeably, though technically they aren’t quite the same. Septicemia, the state of having bacteria in your blood, can lead to sepsis. Sepsis is a severe and often life-threatening state of infection if it’s left untreated. But any type of infection — whether bacterial, fungal, or viral — can cause sepsis. And these infectious agents don’t necessarily need to be in a person’s bloodstream to bring about sepsis.

Such infections most commonly occur in the lungs, abdomen, and urinary tract. Sepsis happens more often in people who are hospitalized, where the risk of infection is already higher. Because blood poisoning occurs when bacteria enter your bloodstream in conjunction with another infection, you won’t develop sepsis without having an infection first.

Some common causes of infections that can cause sepsis include:

  • abdominal infection
  • an infected insect bite
  • central line infection, such as from a dialysis catheter or chemotherapy catheter
  • dental extractions or infected teeth
  • exposure of a covered wound to bacteria during surgical recovery, or not changing a surgical bandage frequently enough
  • exposure of any open wound to the environment
  • infection by drug-resistant bacteria
  • kidney or urinary tract infection
  • pneumonia
  • skin infection

These 3 germs that most frequently develop into sepsis are:

  • Staphylococcus aureus (staph)
  • Escherichia coli (E. coli)
  • Some types of Streptococcus

Who is at risk for blood poisoning

Some people are more susceptible than others to sepsis. Those who are more at risk include:

  • people with weakened immune systems, such as those with HIV, AIDS, or leukemia
  • young children
  • older adults
  • people who use intravenous drugs such as heroin
  • people with poor dental hygiene
  • those using a catheter
  • people who’ve had recent surgery or dental work
  • those working in an environment with great exposure to bacteria or viruses, such as in a hospital or outdoors

Sepsis or blood poisoning is the body’s most extreme response to an infection. Sepsis that progresses to septic shock has a death rate as high as 50%, depending on the type of organism involved. Sepsis is a medical emergency and needs urgent medical treatment. Without treatment, sepsis can quickly lead to tissue damage, organ failure, and death.