Years ago we only had to worry about contracting Lyme Disease from a deer tick bite in a few areas of the U.S. Now, not only has the tick’s range expanded to more parts of the country, the number of diseases they may be carrying is also growing and public health officials are concerned.
According to new research from the Yale School of Public Health, one emerging tick-borne disease, babesiosis, is expanding its range in areas of the northeast where it has become well-established.
Babesiosis is caused by the parasite Babesia microti. It is similar to malaria in that it invades and destroys red blood cells. In the U.S., this parasite is the most common pathogen transmitted through blood transfusions.
Symptoms of an infection include fever, fatigue, chills, headache, sweats and muscle pain. Infection can be asymptomatic or severe, causing death in about 6 to 9 percent of patients. Infection through transfusion has a higher fatality rate. In all cases it is treated with antibiotics.
Babesiosis was first reported in Connecticut in 1991 but is now considered endemic in Massachusetts, Minnesota, New Jersey, New York, Rhode Island, and Wisconsin as well as Connecticut. And cases have turned up in at least 8 other states, from Washington to northern California in the West and from Maine to Maryland in the East.
Risk of Encephalitis
Also of concern are two tick-borne viruses, deer tick virus and Powassan virus (POWV) that can cause fatal encephalitis, inflammation of the brain. Moreover, the number of cases appears to be rising rapidly. Between 1958 and 2003—a span of 45 years—only about 40 cases of POWV were reported in the United States and Canada. Then, in four years, from 2008 to 2012, 21 cases were reported from Wisconsin and Minnesota, and 12 cases from New York State.
These viruses have also been reported in Pennsylvania, New Jersey, Massachusetts, Connecticut, Maine and Vermont. Many of these viral infections are mild or asymptomatic. But more severe infections can progress to encephalitis, which can have a case fatality rate of up to 15 percent and cause permanent nerve or brain damage in about 50 percent of diagnosed cases.
And that's not all. Deer ticks also are known to transmit a bacterial disease known as HGA (human granulocytic anaplasmosis) Also known as ehrlichiosis, HGA has become the third most frequent vector-borne disease in North America and Europe. (Vector-borne diseases are those transmitted to humans by blood sucking insects such as mosquitoes, fleas and lice or arachnids such as mites and ticks.)
HGA attacks white blood cells, and while milder forms cause fever and muscle pain, it can also cause serious disease and immune system malfunction that can lead to opportunistic infections. It is related to Rocky Mountain spotted fever (transmitted by another tick species) and typhus (transmitted by lice.)
How to Protect Yourself
It was only a few months ago that we reported on an uptick in the number of cases of Lyme Disease. These tips to prevent infection are all the more important now.