A tick-borne illness is making its rounds in new parts of America

Babesiosis, a rare tick-borne illness, is spreading through parts of the U.S. The disease could be especially dangerous for those with weakened immune systems and experts say it is only expected to spread more widely as climate change raises temperatures. Other insect-borne illnesses are also likely to increase as a result of warming temperatures.

An unprecedented up-tick

Babesiosis is a rare illness spread through blacklegged or deer tick bites. Now, the disease has expanded its range in the U.S., according to an article published in the Journal of Medical Entomology. The disease has been "historically concentrated in the Northeast and Upper Midwest," but "is now expanding in the Mid-Atlantic region," said a press release about the journal article. This includes rising cases in Connecticut, Massachusetts, Minnesota, New Jersey, New York, Rhode Island and Wisconsin. However, the largest hotspot was found to be Baltimore and the Delmarva Peninsula, which is an "180-mile-long coastal landmass comprising parts of Delaware, Maryland and Virginia," said Grist.

So far, "there are not many cases," Ellen Stromdahl, a retired tick researcher from the Defense Centers for Public Health and the lead author of the journal article, said to The Baltimore Banner. "We think it's the tip of the iceberg and we want to give an early warning." The number of cases is likely to be underrepresented as well, because medical experts may not know to even test for it.

The good news is that approximately one quarter of babesiosis cases are asymptomatic. However, "people who do develop symptoms, especially older adults and immunocompromised people, can get quite sick with fever, chills, anemia, fatigue and jaundice," said Grist. "Untreated, the parasites, which infect and destroy red blood cells, can lead to organ failure and death." Many of the ticks spreading babesiosis also carry Lyme disease. "The Lyme-babesiosis connection is an active area of research," said Grist. "Experts suspect ticks infected with one of the diseases are more predisposed to be infected with the other, but they still don't know why exactly."

The tick of the iceberg

Climate change is to blame for the increases in the range of babesiosis. "Climatic conditions in the southern mid-Atlantic have always been welcoming for ticks," said Grist. "But warmer-than-average winters that have been occurring with grim regularity in recent years are turning some states in the region into year-round breeding sites for ticks." In addition, "reforestation efforts have supported an overpopulation of white-tailed deer," which are capable of carrying ticks over long distances," said Smithsonian Magazine. Suburban expansion has also put more humans in the habitats of ticks.

Ticks are not the only insects expanding their range and spreading disease. Mosquito-borne illnesses have also been rising rapidly and spreading to parts of the world they were not previously present in. "Education about this emerging risk, including how to prevent infection in the first place, how to recognize infection, and appropriate treatment, should be increased for medical providers, public health practitioners and the general population," said the press release.