Joseph Elone had persistent, minor symptoms for about two weeks, but his parents never suspected that it was anything too serious. Then, suddenly, the 17-year-old New Yorker collapsed at a family function and was pronounced dead hours later. Doctors now believe the teen died from Powassan encephalitis, a rare tick-borne virus.

According to the Poughkeepsie Journal, Elone had a minor cough, fatigue, and a headache. He went to the doctor when the symptoms persisted, but was relieved when tests for Lyme disease and strep throat came back negative. The doctor told him to just rest and stay hydrated.

On Aug. 4, Elone collapsed on the front lawn in the early evening. Paramedics arrived and were able to get his heart pumping again, but he died a few hours later.

Doctors at Westchester Medical Center were unable to diagnose his condition when he arrived. Everyone was stumped. But, after the family granted doctors permission to perform an autopsy, they did find what they believe to be traces of the Powassan virus.

“The screening test is not a definitive test,” said Dr. Kari Reiber, Dutchess County interim health commissioner. “It just shows there are antibodies present. But that doesn’t necessarily mean that the person has the disease.”

Encephalitis is an inflammation of the brain. Powassan encephalitis is the only known tick-transmitted strain of encephalitis in the United States. According to Mayo Clinic, people with encephalitis have either no symptoms or mild flu-like symptoms, which make the virus hard to diagnose. Symptoms include headache, fever, muscle aches, and fatigue. More severe symptoms, like severe headaches and altered consciousness, require immediate medical attention.

"There are no diagnostic tests for the disease, and no treatments that are effective," said Dr. David Roth, co-chair of the Tick-Borne Disease Alliance.

Elone’s family is mourning the loss of one of the town’s rising stars. The high school senior had plans to attend Brown University. He was an honors student. "He's a kid who knew who he was. He had all kinds of ambition. Teachers couldn't stop speaking well of him.I just miss my son," Elone’s father said in tears. "I just miss my son. I just miss my son."