Merck Manual

Please confirm that you are not located inside the Russian Federation


Overview of Bacterial Infections in Children


Geoffrey A. Weinberg

, MD, University of Rochester School of Medicine and Dentistry

Last full review/revision May 2020| Content last modified May 2020
Click here for the Professional Version
NOTE: This is the Consumer Version. DOCTORS: Click here for the Professional Version
Click here for the Professional Version
Topic Resources

Bacteria are microscopic, single-celled organisms. Only some bacteria cause disease in people. Other bacteria live inside the intestinal tract, genitourinary tract, or on the skin without causing harm. Some bacteria are even thought to help keep people healthy.

Did You Know...

  • Not all bacteria cause disease or infections.

The most common bacterial infections among children are skin infections (including impetigo), ear infections, and throat infections (strep throat). These and many other less common bacterial disorders are treated similarly in adults and children and are discussed elsewhere. Other infections occur at all ages but have specific considerations in children. Several severe bacterial infections are preventable by routine immunization early in childhood.

Risk of bacterial infections in children

Certain children are at particular risk of bacterial infections.

High-risk children include

  • Infants younger than 3 months

  • Children who have no spleen

  • Children who have an immune system disorder

  • Children who have sickle cell disease

  • Children who have cancer

  • Children who have not had recommended vaccinations


  • Tests of blood, body fluids, or tissue samples

  • Culture

Sometimes doctors diagnose bacterial infections by the typical symptoms they cause. Usually, however, bacteria must be identified in samples of tissue, blood, or body fluids, such as urine, pus, or cerebrospinal fluid. Sometimes bacteria from these samples can be recognized under a microscope or identified with rapid detection tests such as tests that look for genetic material from certain bacteria. Usually, however, they are too few or too small to see, so doctors must try to grow (culture) them in the laboratory. It typically takes 24 to 48 hours to culture the bacteria.

Cultures can also be used to test the susceptibility of particular bacteria to various antibiotics. The results can help a doctor determine which drug to use in treating an infected child.


  • Routine immunization

Many bacterial infections in children can be prevented by following the recommended vaccination schedule. Many viral infections (such as measles, polio, hepatitis A, and hepatitis B) can also be prevented with routine immunization.

Bacterial Infections Preventable With Routine Immunization*

* Note: Many viral infections can also be prevented with routine immunization.


  • Antibiotics

  • Sometimes also surgery

Antibiotics are drugs used to treat bacterial infections. There are many different antibiotics. Each one is effective only on certain bacteria, although some are effective against a wider range of bacteria than others. Most often, antibiotics alone can eliminate a bacterial infection. However, when an infection has created a large collection of pus, people sometimes also need surgery to drain the pus. Such infections include abscesses and joint infections.

Doctors may treat certain potentially serious childhood infections with antibiotics before they have the culture results. When results are obtained, the antibiotics are continued or changed as needed. If no bacteria are found, antibiotics may be stopped.

NOTE: This is the Consumer Version. DOCTORS: Click here for the Professional Version
Click here for the Professional Version
Others also read

Also of Interest


View All
The Uterus, Cervix, and Cervical Canal
The Uterus, Cervix, and Cervical Canal
3D Models
View All
How Insulin Works
3D Model
How Insulin Works