A premature baby can develop infections in almost any part of the body; the most common sites involve the blood, the lungs, the lining of the brain and spinal cord, the skin, the kidneys, the bladder, and the intestines. A baby may acquire an infection in utero (while in the uterus) when bacteria or viruses are transmitted from the mother's blood through the placenta and umbilical cord. Infection may also be acquired during birth from the natural bacteria that live in the genital tract, as well as other harmful bacteria and viruses. Lastly, some babies develop infections after birth, after days or weeks in the NICU.

Regardless of when an infection is acquired, infections in premature infants are more difficult to treat for two reasons:

  • A premature baby has a less developed immune system (and fewer antibodies from her mother) than a full-term baby. The immune system and antibodies are the body's main defenses against infection.
  • A premature baby often requires a number of medical procedures including insertion of intravenous (IV) lines, catheters, and endotracheal tubes and possibly assistance from a ventilator. Each time a procedure is performed, there's a chance of introducing bacteria, viruses, or fungi into the baby's system.

If your baby has an infection, you may notice some or all of the following signs:

  • lack of alertness or activity;
  • difficulty tolerating feedings;
  • poor muscle tone (floppy);
  • inability to maintain body temperature;
  • pale or spotted skin color, or a yellowish tint to the skin (jaundice);
  • slow heart rate; or
  • apnea (periods when the baby stops breathing).

These signs may be mild or dramatic, depending on the severity of the infection.

As soon as there is any suspicion that your baby has an infection, the NICU staff obtains samples of blood and, often, urine and spinal fluid to send to the laboratory for analysis. It can take 24 to 48 hours before laboratory studies show any evidence of infection. If there is evidence of infection, your baby is treated with antibiotics; IV fluids, oxygen, or mechanical ventilation (help from a breathing machine) may also be required.

Although some infections can be quite serious, most respond well to antibiotics. The earlier your baby is treated, the better the chances of successfully fighting the infection.