What is an Infectious Disease

An infectious disease, also referred to as a communicable disease, occurs when an organism, such as a virus, bacterium, fungi or parasite, invades your body. While many microorganisms colonize in our bodies and are usually harmless or sometimes helpful, they can sometimes cause disease.

Anyone can catch infectious diseases; however, you can be at a higher risk if you are taking certain medications like steroids, have HIV or AIDS, or have certain types of cancer that weaken your immune system. Certain medical conditions, such as malnutrition, can also elevate your risk for developing infectious diseases.

How Infectious Diseases are Transmitted

Infectious diseases can be transmitted in various ways, including: direct contact, indirect contact, insect bites or food contamination.

  • Direct Contact
    You are at higher risk for contracting an infectious disease if you come in contact with a person who has an infectious disease. Germs can spread through a cough, sneeze, kiss, touch, sexual contact or a blood transfusion. These germs can also be spread by an animal that bites or scratches you. Pregnant women can also transfer the disease to her unborn child.
  • Indirect Contact
    Germs tend to linger on surfaces like tabletops, doorknobs or faucet handles. If an infected person has come in contact with an inanimate object, like those listed above, and you touch them and then wipe your mouth, nose or eyes before washing your hands, you can possibly become infected as well.
  • Food Contamination
    Improperly cooked meats, contaminated water, or improperly washed fruits and vegetables can also transfer infectious diseases to you. E. coli is a common bacterium found in undercooked beef and some unwashed vegetables and fruits.
  • Insect Bites
    There are some germs that are transmitted through the bite of an insect, such as mosquitoes, fleas, ticks or lice. These carriers, also known as vectors, are known for carrying diseases like West Nile virus and Lyme disease.


The signs and symptoms of infectious diseases vary between each type, but generally all types of infectious diseases are accompanied with:

  • A fever
  • Loss of appetite
  • Muscle aches
  • Fatigue

If you have recently come in contact with an ill person, have travelled, eaten improperly prepared foods, been bitten by an insect or animal and are experiencing the symptoms above, please contact your family physician. If an infectious disease is indicated, request your physician refer you to our office for the highest standard of care possible.