Thanks to faculty and students at the Yale School of Public Health (YSPH), users of Apple’s popular iPhone can better protect themselves against Lyme disease, the most prevalent insect-borne disease in the United States.

The new application presents data on the abundance of infected ticks at the location of the user anywhere within the U.S., based on information from the phone’s Global Positioning System (GPS) hardware. If ticks are determined to be present, the user is given a list of precautions to avoid bites. A chart with life-size photos is provided to aid in the identification of black-legged ticks (Ixodes scapularis, also known as deer ticks) at each life stage, useful information because these ticks cannot transmit Lyme disease during some stages. If the user has been bitten, the program provides instructions on how to properly remove a tick, along with a narrated video.

“This is the first health application for smartphones that could have an immediate impact on a major disease” said Durland Fish, Ph.D., professor of epidemiology at YSPH, who oversaw the development of the application.

Lyme disease can be transmitted after 48 hours of feeding by an infected tick, and most physicians will treat patients who experience such bites with a short course of antibiotics to prevent the disease. To help users determine when they were bitten, the application depicts ticks at various stages of blood engorgement and advises patients to seek medical attention if the photos suggest that a removed tick had been attached for 48 hours or longer. A panel of photos of skin rashes characteristic of Lyme disease along with a list of other symptoms also prompts users to seek immediate medical attention if they believe they are infected. To help users obtain medical care in unfamiliar locations, a GPS-based physician locator finds nearby doctors and provides the phone number and directions to each physician’s office.

“You can only get Lyme disease in certain areas, only by certain ticks, and only after a tick has remained attached for a certain amount of time,” says Fish. “Information provided by this app should help many people prevent Lyme disease.”

Content for the application is provided by Lyme disease researchers at the School of Medicine—where Lyme disease was first identified—in cooperation with the U.S. Centers for Disease Control and Prevention, the American Lyme Disease Foundation, and IntuApp, an applications development company in New York City. It is available through the Apple iTunes Store for $1.99, with proceeds supporting the research and education mission of the American Lyme Disease Foundation based in Lyme, Conn.