Overview of Infections in Newborns

An infection in the fetus, which can occur any time before birth, results from an infection in the mother. Sometimes doctors and the mother know she has an infection, but sometimes they do not. The mother's infection is passed to the fetus through the placenta.

Common infections that are passed on via the placenta include rubella Rubella in Newborns Rubella is a typically mild childhood viral infection that may, however, have devastating consequences for infants infected before birth. Rubella is caused by a virus. The fetus or newborn may... read more , toxoplasmosis Toxoplasmosis in Newborns Toxoplasmosis is infection with the parasite Toxoplasma gondii. It usually does not cause problems in healthy adults, but it can cause serious illness in newborns and in people with a... read more , cytomegalovirus Cytomegalovirus (CMV) Infection in Newborns Cytomegalovirus is a common virus that usually causes few or no problems but can cause serious illness in infants who are infected before birth or around the time of birth. Cytomegalovirus infection... read more , Zika virus infection Zika Virus Infection Zika virus infection is a mosquito-borne viral infection that typically causes no symptoms but can cause fever, rash, joint pain, or infection of the membrane that covers the white of the eye... read more , and syphilis Syphilis in Newborns Syphilis is an infection caused by the bacteria Treponema pallidum. It causes serious problems in infants infected before birth. Syphilis is caused by bacteria. Serious complications... read more . Human immunodeficiency virus (HIV) infection Human Immunodeficiency Virus (HIV) Infection in Children and Adolescents Human immunodeficiency virus (HIV) infection is a viral infection that progressively destroys certain white blood cells and makes people more vulnerable to other infections and some cancers... read more and hepatitis B virus infection Hepatitis B Virus (HBV) Infection in Newborns Hepatitis B virus infection causes inflammation of the liver. Newborns may become infected at birth or rarely after birth. Newborns who develop symptoms have jaundice, lethargy, and failure... read more may also sometimes be passed on via the placenta. There are also many rarer infections that can infect the fetus before birth.

Problems for the fetus depend on which organism is causing the infection and when the mother's infection occurred during the pregnancy. Problems that may occur include miscarriage Miscarriage A miscarriage is the loss of a fetus before 20 weeks of pregnancy. Miscarriages may occur because of a problem in the fetus (such as a genetic disorder or birth defect) or in the woman (such... read more , slow growth in the uterus, preterm birth Preterm (Premature) Newborns A preterm newborn is a baby delivered before 37 weeks of gestation. Depending on when they are born, preterm newborns have underdeveloped organs, which may not be ready to function outside of... read more , stillbirth Stillbirth Stillbirth is death of a fetus after 20 weeks of pregnancy. Stillbirth may result from a problem in the woman, placenta, or fetus. Doctors do blood tests to try to identify the cause of a stillbirth... read more , and birth defects Overview of Birth Defects Birth defects, also called congenital anomalies, are physical abnormalities that occur before a baby is born. They are usually obvious within the first year of life. The cause of many birth... read more . An infection may or may not cause symptoms in the mother.

An infection can be acquired during birth if the baby passes through an infected birth canal or if an infection moves up from the vagina if delivery is delayed after the membranes have ruptured.

Infections that can occur during birth include HIV infection Human Immunodeficiency Virus (HIV) Infection in Children and Adolescents Human immunodeficiency virus (HIV) infection is a viral infection that progressively destroys certain white blood cells and makes people more vulnerable to other infections and some cancers... read more , herpes simplex virus infections Herpes Simplex Virus (HSV) Infections Herpes simplex virus infection causes recurring episodes of small, painful, fluid-filled blisters on the skin, mouth, lips (cold sores), eyes, or genitals. This very contagious viral infection... read more , hepatitis B virus infection Overview of Hepatitis Hepatitis is inflammation of the liver. (See also Overview of Acute Viral Hepatitis and Overview of Chronic Hepatitis.) Hepatitis is common throughout the world. Hepatitis can be Acute (short-lived) read more , streptococcal infections Streptococcal Infections Streptococcal infections are caused by any one of several species of Streptococcus. These gram-positive, sphere-shaped (coccal) bacteria (see figure ) cause many disorders, including... read more , E. coli infections Escherichia coli Infections Escherichia coli (E. coli) are a group of gram-negative bacteria that normally reside in the intestine of healthy people, but some strains can cause infection in the digestive... read more , listeriosis Listeriosis Listeriosis is infection caused by the gram-positive bacteria Listeria monocytogenes, usually when contaminated food is eaten. People may consume the bacteria in contaminated dairy products... read more , gonococcal infections Gonorrhea Gonorrhea is a sexually transmitted infection caused by the bacteria Neisseria gonorrhoeae, which infect the lining of the urethra, cervix, rectum, or throat, or the membranes that cover... read more , and chlamydia Chlamydia and Other Nongonococcal Infections Chlamydial infections include sexually transmitted infections of the urethra, cervix, and rectum that are caused by the bacteria Chlamydia trachomatis. These bacteria can also infect... read more . Sometimes these infections can also be passed on through the placenta.

An infection acquired after birth occurs when a newborn has close contact with an infected mother directly or through breastfeeding. An infection acquired after birth can also occur if newborns have contact with infected health care practitioners, family, or visitors in the hospital (see Hospital-Acquired Infections in Newborns) Hospital-Acquired Infections in Newborns Hospital-acquired infections in newborns are infections that develop after newborns have been admitted to the nursery. These infections do not come from the mother when the baby is in the womb... read more or at home.

Infections in newborns are usually caused by bacteria or viruses and less commonly by fungi or parasites. The more common bacteria include group B streptococci Types of streptococci Streptococcal infections are caused by any one of several species of Streptococcus. These gram-positive, sphere-shaped (coccal) bacteria (see figure ) cause many disorders, including... read more , Escherichia coli Escherichia coli Infections Escherichia coli (E. coli) are a group of gram-negative bacteria that normally reside in the intestine of healthy people, but some strains can cause infection in the digestive... read more (E. coli), Listeria monocytogenes Listeriosis Listeriosis is infection caused by the gram-positive bacteria Listeria monocytogenes, usually when contaminated food is eaten. People may consume the bacteria in contaminated dairy products... read more , gonococci Gonorrhea Gonorrhea is a sexually transmitted infection caused by the bacteria Neisseria gonorrhoeae, which infect the lining of the urethra, cervix, rectum, or throat, or the membranes that cover... read more , and chlamydiae Chlamydia and Other Nongonococcal Infections Chlamydial infections include sexually transmitted infections of the urethra, cervix, and rectum that are caused by the bacteria Chlamydia trachomatis. These bacteria can also infect... read more . The more common viruses causing infection in newborns include herpes simplex viruses Herpes Simplex Virus (HSV) Infections Herpes simplex virus infection causes recurring episodes of small, painful, fluid-filled blisters on the skin, mouth, lips (cold sores), eyes, or genitals. This very contagious viral infection... read more (HSV), human immunodeficiency virus Human Immunodeficiency Virus (HIV) Infection in Children and Adolescents Human immunodeficiency virus (HIV) infection is a viral infection that progressively destroys certain white blood cells and makes people more vulnerable to other infections and some cancers... read more (HIV), cytomegalovirus Cytomegalovirus (CMV) Infection Cytomegalovirus infection is a common herpesvirus infection with a wide range of symptoms: from no symptoms to fever and fatigue (resembling infectious mononucleosis) to severe symptoms involving... read more (CMV), and hepatitis B virus Hepatitis B, Acute Acute hepatitis B is inflammation of the liver that is caused by the hepatitis B virus and that lasts from a few weeks up to 6 months. Hepatitis B is spread through contact with blood or other... read more (HBV).

Some infections that can affect people of all ages cause particular problems when they occur in a fetus or newborn. Some of the more serious infections in newborns include the following:

See Candidiasis (Yeast Infection) Candidiasis (Yeast Infection) Candidiasis is infection with the yeast Candida. Candidiasis tends to occur in moist areas of the skin. This skin infection may cause rashes, scaling, itching, and swelling. Doctors examine... read more for infection caused by the fungus Candida.