Pyaemia (or pyemia) is a type of septicaemia that leads to widespread abscesses of a metastatic nature. It is usually caused by the staphylococcus bacteria by pus-forming organisms in the blood. Apart from the distinctive abscesses, pyaemia exhibits the same symptoms as other forms of septicaemia. It was almost universally fatal before the introduction of antibiotics.

Sir William Osler included a three-page discussion of pyaemia in his textbook "The Principles and Practice of Medicine", published in 1892. He defined pyaemia as follows:

Earlier still, Ignaz Semmelweis – who would later die of the disease – included a section titled "Childbed fever is a variety of pyaemia" in his treatise, "The Etiology of Childbed Fever" (1861). Jane Grey Swisshelm, in her autobiography titled "Half a Century", describes the treatment of pyaemia in 1862 during the American Civil War.

The disease is characterized by intermittent high temperature with recurrent chills; metastatic processes in various parts of the body, especially in the lungs; septic pneumonia; empyema. It may be fatal.

Clinical sign and symptoms can be differ according to system it involves.

The main coagulase-positive staphylococcus is Staphylococcus aureus, although not all strains of Staphylococcus aureus are coagulase positive. These bacteria can survive on dry surfaces, increasing the chance of transmission. S. aureus is also implicated in toxic shock syndrome; during the 1980s some tampons allowed the rapid growth of S. aureus, which released toxins that were absorbed into the bloodstream. Any S. aureus infection can cause the staphylococcal scalded skin syndrome, a cutaneous reaction to exotoxin absorbed into the bloodstream. It can also cause a type of septicaemia called pyaemia. The infection can be life-threatening. Problematically, Methicillin-resistant Staphylococcus aureus (MRSA) has become a major cause of hospital-acquired infections, and is being, MRSA has also been recognized with increasing frequency in community-acquired infections. The symptoms of a Staph Infection include a collection of pus, such as a boil or furuncle, or abscess. The area is typically tender or painful and may be reddened or swollen.

"Other infections include:"

- "Closed-space infections of the fingertips, known as paronychia."