Infectious Diseases: Overview


What is an infectious disease?

Infectious diseases can range from common illnesses, such as the cold, to serious illnesses, such as meningitis or AIDS. According to the Centers for Disease Control and Prevention (CDC), an infectious disease is caused by one or more of the following: 

  • Viruses
  • Bacteria  
  • Parasites 
  • Fungi  

What causes infectious diseases?

Depending on the disease-causing organism, an infection can spread in some or all of the following ways: 

  • Airborne transmission - transmission of an infection through inhaling airborne droplets of the disease, which may exist in the air as a result of a cough or sneeze from an infected person
  • Blood-borne transmission - transmission of an infection through contact with infected blood, such as when sharing hypodermic needles
  • Direct skin contact - transmission of an infection through contact with the skin of an infected person
  • Insect-borne transmission - transmission of an infection through insects such as mosquitoes that draw blood from an infected person and then bite a healthy person
  • Food-borne transmission - transmission of an infection through consuming contaminated food 
  • Water-borne transmission - transmission of an infection through contact with contaminated water
  • Sexual transmission - transmission of an infection through sexual contact, including intercourse 

Helpful resources

Children's Hospital Colorado has many publications, all developed with the intention of spreading the word from our pediatric specialists, patients and supporters. 

Bug Watch 
Bug Watch is a passive surveillance system provided as a service to the medical community by Children's Hospital Colorado’s Epidemiology Department and Microbiology/Virology Laboratory. It displays the number of selected microorganisms detected by our laboratory in hospitalized and outpatient children throughout Children's Hospital Colorado system during the indicated weeks.

Keeping Kids Healthy and Immunized 

  • The State of Health of Colorado Children
    This report highlights how effective vaccines are in Colorado and demonstrates the need to better educate parents about vaccine misinformation.

  • Germ Proof Your Kids: The Complete Guide to Protecting (without Overprotecting) Your Kids
    Children’s own Dr. Harley Rotbart, vice chair of the Department of Pediatrics, authored a book about keeping kids healthy.  from Infections (2000), by Harley Rotbart, MD, is published by ASM Press.