A Southern California boy faces a potentially lengthy recovery after being hospitalized with West Nile virus, prompting his mother to warn other parents about the early signs as Los Angeles County sees a record number of mosquito-borne infections.

As 13-year-old Joseph Vasquez remains unable to walk while being treated at Los Angeles Children’s Hospital, his mother, Maria Salazar, told NBC Los Angeles that she was fearful her son could die.

It all started with a rash that looked like chickenpox, according to Salazar. Then Joseph took a fall at school before developing other symptoms, including a fever, loss of appetite and headaches.

“We ended up taking him to the emergency room because I found him facedown on the ground,” the mother said, explaining that Joseph had been losing his balance before he was diagnosed with West Nile virus. “It just started to be from the lower body, and then he couldn’t even feel his toes or movement.”

The Centers for Disease Control and Prevention estimates that about 80% of West Nile virus infections are asymptomatic, while less than 1% of infected people develop neuroinvasive disease.

“Most of the cases, we have fever, maybe you just feel like funny,” Dr. Ilan Shapiro of AltaMed Health Services said. “But there are cases, and that’s why it’s so important to talk about these viruses that can have problems, neurologically speaking, in our kids.”

Shapiro, who is not Joseph’s doctor, said inflammation caused by the infection may be making it challenging for the 13-year-old to walk.

“Our body is actually made of nerves and other things that actually connect our brain to our body. Sometimes that part of the connection can actually get inflamed, and that’s where you can actually have this,” the doctor explained.

Salazar, who initially thought her son had a common cold, now urges other parents to take proper precautions when kids go outdoors and pay attention to symptoms — the signs she initially brushed off.

“They should be looking out for any mosquito bites, dizziness, headaches, blurry vision, falling, losing balance,” she said. “If your kids are telling you, ‘Hey, my head hurts,’ and they’re scratching, take them to the doctor.”

Dr. Shapiro said it’s important to seek medical attention if people experience symptoms such as fever, chills, brain fog and fatigue, especially after spending time outdoors.

Los Angeles County has recorded 135 confirmed West Nile virus infections this year, including 130 hospitalizations and five deaths, according to the county Department of Public Health.