The overall mortality rate for E. coli O157:H7 is <1%. For those who develop hemolytic uremic syndrome, the death rate is between 3-5% (www.azdhs.gov)

Microbial Group: 
Bacterium

Untreated, tularemia has a mortality rate of 5-15%; this rate is even higher with the typhoidal form. Appropriate antibiotics lower this rate to about 1% (Medscape)

Giardiasis is not associated with mortality except in rare cases of extreme dehydration, primarily in infants or malnourished children (Medscape)

Microbial Group: 
Protozoan

Giardia muris is a parasite that causes the disease giardiasis, Some symptoms of Giardiasis are: diarrhea, gas, greasy stool, nausea, cramps, and dehydration.

Microbial Group: 
Protozoan

The Hepatitis A virus causes Hepatitis A. The symptoms of this infectious disease of the liver are: nausea, vomiting, diarrhea, jaundice, fever, and abdominal pain. 

Microbial Group: 
Virus

Human Astrovirus causes infectious diarrhea, nausea, vomiting, fever, and abdominal pain. 

Microbial Group: 
Virus

In 2007, influenza caused 411 deaths: 79 of them in persons aged 75-84 years and 139 of them in persons aged 85 years and older (Xu et al, 2007)

Microbial Group: 
Virus

About 15%-20% of hospitalized Lassa fever patients will die from the illness. It is estimated that the overall mortality rate is 1%, however during epidemics mortality can climb as high as 50% (Wikipedia)

Microbial Group: 
Virus

Legionnaires disease has a 25% mortality rate (Medscape)

Microbial Group: 
Bacterium

Listeria monocytogenes is a bacterium that can cause the disease listeriosis. It is a series disease, especially for pregnant women, people with a weakened immune system, and adults over the age of 65. It causes a variety of symptoms depending on the location the bacterium is affecting. Basic symptoms include fever and diarrhea. However, if the bacteria travels further than the gut, the symptoms depend on if the person is pregnant. If it is a woman who is pregnant, symptoms are usually flu like, however, the infection may lead to miscarriages or life-threatening infections to the newborn. If the people are not pregnant, symptoms can include headaches, stick neck, loss of balance, and convulsions.

Microbial Group: 
Bacterium