A new tick-borne illness called ehrlichiosis is spreading in the Mid-West, and could be on the move to other parts of the United States.

Ehrlichiosis is an illness caused by an unnamed bacteria. It is transmitted by deer ticks and so far has effected 25 people in Wisconsin and Minnesota. Deer are notorious for spreading Lyme disease, and recently the insects have been found carrying diseases such as the malaria-like parasite Babesiosis and bacterial Anaplasmosis.

Ehrlichiosis attacks and kills the white blood cells, making an infected person feel "flu-like." It was originally found in 1999, but researches say the disease could be effecting more people than reported.

"So far we have tested thousands of patients from around the United States, and we have only found it in the blood of patients from Wisconsin and Minnesota," said lead researcher Dr. Bobbi Pritt, director of the Clinical Parasitology and Virology Laboratories at the Mayo Clinic, according to USNews.

"We have also found it in ticks. Specifically, in the ticks called Ixodes scapularis, also known as the deer tick," she said. "That's the same little tick that transmits a number of really serious diseases -- Lyme disease, anaplasmosis and babesiosis," she added.

"Ehrlichiosis is an emerging disease. Its range is expanding throughout the United States," she said.

Before the recent outbreak, there were an average of 0.7 cases of ehrlichiosis reported per million people annually. The most common symptoms are headache, muscle aches, and fatigue, and a rash occasionally occurs. The serious effect of the disease is that bacteria damage the immune system, making the body susceptible to other diseases, most notably fungal infections.

"Before this report, human ehrlichiosis was thought to be very rare or absent in Minnesota and Wisconsin," Dr. Pritt said. "Therefore, physicians might not know to look for Ehrlichia infections at all."

The illness takes about seven to nine days to incubate after the initial tick bite, according to the National Center for Biotechnology Information. Recovery takes about sick weeks, but the most serious symptoms of ehrlichiosis include coma, kidney and lunch damage, seizure, and even death.

Anyone bitten by a tick your consult a doctor. Ehrlichiosis can be treated with antibiotics.

According to researchers, the number of diseases transmitted from animals to humans has been increasing recently. It was discovered that bats can carry the deadly Hendra virus, and that rats have been spreading the Hanta virus, famously related to Ebola.