The “bull’s-eye” rash is a symptom of Lyme Disease, which is commonly caused by tick bites. Dr. Maria Diuk-Wasser visited Stony Brook University to give seminar about the emergence of this disease this past Wednesday. WIKIMEDIA COMMONS VIA CC BY-SA 2.5

Associate Professor of Ecology, Evolution and Environmental Biology at Columbia University, Dr. Maria Diuk-Wasser, visited Stony Brook University to give a seminar titled, “Lyme Disease Emergence: A Coupled Natural and Human System” on Wednesday, Sept. 26.

Lyme disease has become one of the most common tick-borne diseases in the United States in recent years. It is caused by a type of bacteria called Borrelia burgdorferi, which is spread through tick bites. Once the pathogen is carried into the body, people begin to experience flu-like symptoms, such as a severe headache and cardiac symptoms, in addition to a skin rash.

According to Diuk-Wasser’s research, there are approximately 30,000 cases reported annually and the number of reported cases has gradually increased over the years.

One of Diuk-Wasser’s goals is to create a sophisticated spatial map that shows the risk of tick-borne disease. The map will analyze historical changes of the spreading of tick-borne pathogens and study changes in the landscape caused by human modification. She hopes this will help prevent future increases in cases of Lyme disease on Long Island and in New York in general.

“The expansion of New York’s deer population as a result of deforestation has played a role in spreading the disease,” Diuk-Wasser said. Despite this, “deer have a dual role. They create ticks, but they can reduce infection.”

In her research, Diuk-Wasser found that small mammals and birds are the main bacteria carriers. Because of this, she concluded that forest fragmentation — which displaces these animals from their native habitats and decreases biodiversity among tick species — leads to an increased risk of disease for humans. The entire process is known as the dilution effect.

On the other hand, Diuk-Wasser noted that urbanization can also lead to a decrease in ticks and pathogens. Wasser collected the number of ticks on mice and birds and calculated the rate of infection for humans in different environments. She found that more populated and urbanized areas were less hazardous than suburban areas.

“We should always be thinking of this coupling system between natural system and human system rather than individually,” she said.

Students who attended the lecture, including graduate student in the School of Marine and Atmospheric Sciences, Christopher Brianik, found Diak-Wasser’s presentation of her research compelling. “It was very interesting to see how the ticks change their parasite host frequently which causes disease dynamics,” he said.