The return from a day outdoors can quickly turn from refreshing to alarming upon discovering a tick attached to your skin. Not only are these unwelcome parasites feeding on your blood, but they can also transmit bacteria and viruses linked to over 15 diseases, including Lyme disease and Rocky Mountain spotted fever, according to the U.S. Centers for Disease Control and Prevention (CDC).
Among these diseases, babesiosis has gained attention as a significant public health concern. Commonly referred to as “American malaria,” babesiosis is caused by a parasite transmitted by ticks, infecting red blood cells and causing symptoms such as fever, chills, nausea, and altered mental states. A recent study published in Open Forum Infectious Diseases highlights a troubling increase in babesiosis cases across the United States, often occurring alongside other tick-related infections.
The research team, led by infection disease fellow Paddy Ssentongo at Penn State Health Milton S. Hershey Medical Center, examined over 3,500 cases of babesiosis from 2015 to 2022. The findings reveal a startling annual increase of 9% in babesiosis cases, primarily attributed to climate change expanding the range of the black-legged tick, the main vector for the disease. In particular, the Northeast has witnessed an explosive rise: cases in Maine surged by 1,422% and by 1,602% in Vermont between 2011 and 2019.
Geographical factors are compounded by the fact that ticks are now carrying more pathogens than ever. These ticks, which may travel on deer, acquire diseases by feeding on infected mice and other small mammals, then transmit these infections to humans through bites. The study found that 42% of individuals with babesiosis also had one or more other tick-borne infections. Among these, 41% were co-infected with Lyme disease.
While this data might initially seem alarming, the study reveals a paradox. Surprisingly, individuals infected with multiple pathogens may experience a lower risk of death from babesiosis than those infected with babesiosis alone. Ssentongo noted that having both babesiosis and Lyme disease did not correlate with increased mortality. It is hypothesized that the presence of multiple infections could enhance the immune response, providing better protection against the diseases.
Furthermore, the treatment regimens for these tick-borne illnesses differ, with babesiosis typically treated using a combination of antibiotics azithromycin and atovaquone. In contrast, doxycycline is the first-line treatment for Lyme disease and other tick-borne diseases. This raises questions about whether doxycycline might also be effective against babesiosis, highlighting the need for further research.
Preventing tick-borne diseases remains the most effective strategy. Experts recommend wearing long-sleeved clothing, applying insect repellent, and conducting thorough tick checks after spending time outdoors. These precautions are essential as the incidence of tick-related diseases continues to rise across the nation.
