Moises Ponce Mendoza was 17 years old when he died on August 31, just weeks after contracting a rare brain-eating amoeba infection. His family in North Carolina have now spoken out about the days leading up to his death, describing the moment they realised something was terribly wrong and their desperate search for answers about where he contracted the illness.

Brain-eating amoeba infections, caused by Naegleria fowleri, are extremely rare, with fewer than 10 cases reported annually in the United States. The organism is typically found in warm, stagnant freshwater such as lakes, rivers and hot springs, and enters the body through the nose. The infection it causes, primary amebic meningoencephalitis, is almost always fatal and progresses rapidly once symptoms begin.

Moises' mother, Monica Mendoza, described her son's final days in an interview with Univision, recounting the moment she first knew something was wrong.

"He started acting like crazy, screaming like crazy and grabbing his head," she said. "And I started crying, and I held him and said, 'My son, what's wrong with you?'"

That was the last time she saw him conscious. He fell into a coma shortly afterwards and died just days later.

Monica has described coming home to a house where her son is no longer present as something she cannot comprehend.

"How am I going to live with this void?" she said. "I come home, and he's not there."

Since his death, the family have been retracing his final days in an attempt to establish where he might have been exposed. His brother Elmer Aguilar Mendoza reflected on their shared love of swimming and the many places they had visited together.

"We always went to many different places to swim. We always loved that. Lakes, pools, many places," he said tearfully. "I wish I could go back in time, hug him, and tell him just how much we loved him. My kids, my nephews loved him very much."

No source of exposure has yet been confirmed. Monica has pleaded publicly for help in finding answers, saying she hopes that understanding how Moises was infected could help protect others from the same fate.

"Please, pay close attention and do your part to find where this came from so we can protect everyone else," she said.