Elizabethkingia anophelis is a bacterium that is spreading quickly across the Midwest. To date, infection from the bacteria has caused illnesses in Wisconsin, Michigan and Illinois — resulting in the loss of 20 lives. At this point, the list of things that health experts don't know about Elizabethkingia anophelis is longer than the list of things they do. For instance, researchers aren't exactly sure how people are becoming infected. Nor do they know how the illness is spreading. But here's what they do know about the mysterious Elizabethkingia anophelis and how you can keep your family safe.

Elizabethkingia anophelis is commonly found in water and soil.

While health experts don't know exactly how patients are becoming infected, they do know that Elizabethkingia is commonly found in river water and reservoir soils. The Centers for Disease Control and Prevention (CDC), along with the health departments of affected states, are currently testing water and environmental samples from a variety of potential sources (including things found in and around hospitals) but none of these have been found to be a source of the bacteria.

The bacteria are most likely to infect those with a weakened immune system.

For the vast majority of people, Elizabethkingia anophelis does not cause an infection. Symptoms of the disease include fever, chills, cellulitis and shortness of breath. It does not usually cause serious infections in humans, but when it does strike, it usually hits those with an already weakened immune system. "The majority of individuals who are affected are over the age of 65 and almost all of them have some prior health condition," said Dr. Nirav Shah, director of the Illinois Department of Public Health.

Elizabethkingia infections have so far been reported in Michigan, Wisconsin and Illinois.

Wisconsin has reported 59 confirmed cases of Elizabethkingia; 18 of those have resulted in deaths. Michigan and Illinois have each reported one case, both resulting in deaths.

Treatment options are available, but only at early stages.

According to the CDC, there are several antibiotics that can be used to treat Elizabethkingia infections, but only when the disease is caught early on.

The bacterium was named after a female microbiologist.

Dr. Elizabeth King discovered and named the bacteria in 1959.

What you need to know about the Midwest's mysterious bacterial outbreak
Elizabethkingia anophelis is spreading across the Midwest, claiming 20 lives so far.