WARWICK, R.I. (AP) – A 7-year-old boy has died from encephalitis, an inflammation of the brain, and one of his elementary school classmates also contracted a neurological virus this month. Doctors are investigating whether the two cases are related.

“I wish we had the answers, but right now we don’t,” said Dr. Utpala Bandy, the state’s chief epidemiologist. “This investigation is not over.”

Dylan Gleavey, a second-grader at Greenwood Elementary School, died last week and was buried on Wednesday. He had been admitted to Hasbro Children’s Hospital on Dec. 1. The boy’s mother, Denise Spoerer, said her son had been suffering from a cold and was diagnosed with a serious sinus infection at a walk-in clinic. He suffered a seizure the next day and was taken to Hasbro’s, where he was diagnosed with encephalitis.

Signs of the illness can include a stiff neck, nausea, disorientation and seizures.

A classmate was admitted this month to the same hospital with viral meningitis, but she has since recovered.

The second-grade classroom has been cleaned with bleach and is safe for students’ return, health officials said. The School Department will continue to monitor the situation, said School Superintendent Robert J. Shapiro.

Doctors with the federal Centers for Disease Control and Prevention in Atlanta are helping with the investigation.