Cold, Flu & Infections

Welcome to Cold, Flu & Infections Center, online resource for important information related to infectious diseases. Here you will learn about the basics of the immune system, how infectious diseases are transmitted into the body and ways to prevent such illnesses.

Get answers to concerns about the common cold, flu, strep throat, as well as bird flu, SARS and hantavirus pulmonary syndrome.

Topics of interest include ear and eye infections, animal- and insect-borne diseases, as well as sexually transmitted diseases, and information about bioterrorism.

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Cold & Flu Basics

Colds and flu affect most people at some point. Common colds are minor upper respiratory infections caused by hundreds of different viruses and are highly contagious. Influenza is one of the most common infectious viral diseases. The flu may be prevented in many people who receive the flu vaccine. Bird flu is caused by viruses that in rare cases may spread from birds to people.

Parasitic Diseases

Parasitic diseases occur when an organism invades a person's body and finds nourishment inside the host. Parasites range from tiny, single-celled organisms to multicellular worms (helminths, including tapeworms and roundworms) that may be visible.

Tropical diseases

A tropical disease is an illness most common or limited to tropical or subtropical areas. Hemorrhagic fevers include several illnesses that affect multiple organ systems. Examples include Ebola hemorrhagic fever and yellow fever.

Fungal Infection

Fungi are plant-like organisms that may cause infection. Many different types of fungi can affect the skin. Some are naturally present in the human body and are called yeast.



Sexually transmitted diseases

Sexually transmitted diseases (STDs) are passed from person to person during sexual activity. STDs such as chlamydia and gonorrhea are caused by bacteria. Single-celled organisms called parasites cause trichomoniasis.

Learn more about Infections


Infectious Disease Basics

Infectious disease refers can be transmitted from one living thing to another. In most people, the immune system responds effectively to minor infections. Vaccinations have helped curb or eliminate many once-feared viruses. Bacterial infections include staph infections and strep infections. Serious staph infections, such as MRSA, often occur in hospitals.

  • Rabies
  • Animal Borne Diseases
  • Infection Related Blood Tests
  • Enterovirus Infection
  • Immune System
  • Lyme Disease
  • Necrotizing Fasciitis
  • Polio
  • Staph Infections
  • Strep Infections
  • Toxic Shock Syndrome
  • Transmission Basics
  • Urine Tests & Infections
  • Vaccination

Skin Related Infections

Infections related to the skin can stem from many sources, including inflammation of a hair follicle (folliculitis), sexually transmitted behavior (AIDS skin conditions, herpes simplex viruses), diseases traditionally associated with childhood (measles, mumps, rubella, impetigo, fifth disease, and hand, foot and mouth disease) and reactions to medication or illness (Stevens Johnson syndrome).

Some infections leave pockmarks, including chickenpox (and later shingles), monkey pox and smallpox. Other skin-related infections include leprosy, and cellulitis (including a subtype called erysipelas). While not technically infections, insect bites, stings and infestations related to the skin include head lice, scabies and unidentified skin parasite infections.

  • Cat Scratch Disease
  • Cellulitis
  • Chickenpox
  • Slapped Cheek
  • Folliculitis
  • Hand, Foot and Mouth Disease
  • Head Lice
  • Impetigo
  • Insect Bites
  • Leprosy
  • Measles
  • Molluscum Contagiosum
  • Mumps
  • Pityriasis Rosea
  • Roseola
  • Rubella
  • Scabies
  • Scarlet Fever
  • Smallpox
  • Stevens Johnson Syndrome
  • Tinea Versicolor

Bioterror Related Diseases

Bioterror-related diseases are illnesses contracted after the deliberate release of disease-causing agents, such as bacteria, viruses, and other germs and toxins. Other potential threats include botulism, plague, the poison ricin and tularemia, a highly infectious bacterium.

Pneumonia & Lung Infection

Common lung infections include bronchitis and pneumonia. Infections such as whooping cough and tuberculosis have been largely confined recently in the United States, although they still occur occasionally.

Brain Related Infections

Brain-related infections involve illnesses that affect the brain, the spinal cord and their surrounding structures. Bacteria and viruses are the microorganisms most often responsible for these infections. Brain-related infections are relatively rare.

  • Encephalitis
  • Meningitis
  • Tetanus
  • West Nile Virus