Critical Illnesses - Infectious Diseases


critical illness infectious diseases

Table of Contents

What is Malaria?

What are the Usual Symptoms of Malaria?

How is Malaria Usually Treated?

Can Malaria be Prevented?

What is a Encephalitis?

What are the Usual Symptoms of Encephalitis?

How is Encephalitis Usually Treated?

Can Encephalitis be Prevented?

What is Legionnaires’ Disease?

What are the Usual Symptoms of Legionnaires’ Disease?

How is Legionnaires’ Disease Usually Treated?

Can Legionnaires’ Disease be Prevented?

Covering high-level, basic information about three infectious diseases: malaria, encephalitis, and Legionnaire’s disease. *

Malaria

What is Malaria?

Malaria is a parasitic disease that most commonly enters the bloodstream through a mosquito bite. Plasmodium parasites from infected mosquitos travel through the bloodstream to the liver. Some parasite types can lay dormant for up to a year, but at some point, the parasite will begin to infect red blood cells. The infected red blood cells can burst as they travel throughout the body, spreading more parasites.

What are the Usual Symptoms of Malaria?

Malaria symptoms generally include:

  • Fever and flu-like illness, including shaking chills, headache, muscle aches, and tiredness.
  • Nausea, vomiting, and diarrhea may also occur.
  • Malaria may cause anemia and jaundice (yellow coloring of the skin and eyes) because of the loss of red blood cells. If not promptly treated, the infection can become severe and may cause kidney failure, seizures, mental confusion, coma, and death.

How is Malaria Usually Treated?

Antimalarial drugs are available for treatment – doctors base the exact type of drug prescribed on the type of malaria, where the person was infected, the person’s age, whether they are pregnant, and how sick they are at treatment start. Both the CDC and WHO have guidelines for treating malaria.

Can Malaria be Prevented?

Speak with your doctor at least 4-6 weeks before traveling to places known for malaria transmission. The 4-6 weeks should allow enough time for any prescribed antimalarial drugs to become effective. The CDC also recommends sleeping under insecticide-treated bed nets, using insect repellent, and wearing long-sleeved clothing when outside.

Encephalitis

What is Encephalitis?

From “encepahlo” (brain) and “itis” (inflammation), encephalitis is inflammation of the brain. The most common cause of encephalitis is a viral infection.

What are the Usual Symptoms of Encephalitis?

Encephalitis often causes only mild flu-like symptoms (fever/headache) or no symptoms at all. It can also cause confused thinking, seizures, or problems with movements or senses (sight/hearing).

Severe cases include:

  • Severe headache
  • Sudden fear
  • Drowsiness
  • Vomiting
  • Confusion
  • Seizures

How is Encephalitis Usually Treated?

  • Oral and intravenous (IV) medicines to reduce inflammation and treat infection.
  • Antibiotics that address underlying bacterial infections.
  • Antiviral medications.
  • Medications or other therapies to control seizures.

Can Encephalitis be Prevented?

Maintaining proper hygiene and handwashing, avoiding mosquito and tick exposure, and keeping vaccinations up to date. Consult your healthcare provider before traveling to areas known to have encephalitis-causing viruses to see what vaccines may be needed in preparation.

Legionnaires’ Disease

What is Legionnaires’ Disease?

A severe form of pneumonia caused by a bacterium known as legionella, most commonly contracted from inhaling the bacteria from water or soil. Legionella is found naturally in freshwater environments such as lakes and streams, but it can grow in:

  • Showerheads and sink faucets
  • Cooling towers
  • Hot tubs that aren’t drained after each use
  • Decorative fountains and water features
  • Hot water tanks and heaters
  • Large plumbing systems

What are the Usual Symptoms of Legionnaires’ Disease?

Legionnaires’ disease is a severe form of pneumonia and has similar symptoms that usually develops 2-10 days after exposure. Common initial symptoms include:

  • Headache
  • Muscle aches
  • Fever that may be 104 F or (40 C) or higher

Symptoms starting on the second or third day usually include:

  • Cough – look for mucus and sometimes blood
  • Shortness of breath
  • Chest pain
  • Gastrointestinal symptoms, such as nausea, vomiting, and diarrhea
  • Confusion or other mental changes

Most healthy people do not get sick when exposed to Legionella. People who have an increased risk include:

  • Smokers – former/current
  • Those with weakened immune system
  • Those with chronic lung disease or other serious conditions (diabetes, kidney failure, liver failure)
  • People 50 years or older
  • People with cancer

How is Legionnaires’ Disease Usually Treated?

Legionnaires’ disease requires antibiotics and most cases of it can be successfully treated this way.

Can Legionnaires’ Disease be Prevented?

People generally spread Legionnaires’ disease to others only under rare circumstances.

One of the most important steps in preventing Legionnaires’ disease is to maintain water systems as previously mentioned: hot tubs, hot water tanks and heaters, large plumbing systems, cooling towers, and decorative fountains.

This blog post is for informational purposes only. It is not intended to diagnose or treat any conditions or illnesses or act as a substitute for professional medical advice. Consult your healthcare provider if you have questions or concerns about any of the topics discussed above.

Back to Top

  1. CDC. Malaria: About Malaria.
  2. Mayo Clinic. Malaria
  3. Mayo Clinic. Encephalitis.
  4. Johns Hopkins Medicine. Encephalitis.
  5. U.S. National Library of Medicine. Medline Plus. Encephalitis.
  6. CDC. Legionella (Legionnaires’ Disease and Pontiac Fever).