A Fairfax County schoolteacher has been found to have viral meningitis, bringing to three the number of confirmed cases in the county over the past week.

The teacher at Armstrong Elementary School in Reston was hospitalized late Friday, authorities said yesterday. Citing privacy rules, health officials said they could not release the patient's name, age or the grade that he or she teaches.

Two 16-year-old students at Chantilly High School were infected last week. Health officials confirmed that both suffered from viral meningitis, which left one of the girls dead.

No link has been found among the cases.

Courtney "Kay" Richard, a sophomore, died Thursday of meningitis after four days in hospitals. The other Chantilly student, who has not been identified, is recovering. She was being treated at Inova Fairfax Hospital and showing signs of improvement yesterday, said Kimberly Cordero, a spokeswoman for the Fairfax County Health Department. The girl was listed in stable condition.

A 12-year-old boy who attended Franklin Middle School in Chantilly died last week, but authorities do not believe meningitis was the cause. The results from his autopsy are expected this week, said Gloria Addo-Ayensu, Fairfax's director of health.

Health officials said they had no reason to believe that the Reston case is connected to those in Chantilly. The infected teacher does not know the students from Chantilly and has had no known contact with them, authorities said. The two western Fairfax communities are about seven miles apart.

It could be a week before officials determine whether the two Chantilly High School cases are definitively linked, said Kitty Porterfield, a Fairfax schools spokeswoman. Initially, officials were not sure what form of meningitis the girls had, but the Health Department confirmed yesterday that it was viral.

Craig DuBois, president of Armstrong Elementary's PTA, said he is concerned about the new meningitis case involving the teacher at his 7-year-old son's school.

"I would be even more concerned if school were still in session," DuBois said. The school year ended Friday for most Fairfax schools.

"Now it's less likely that if someone were infected, that they would pass it on," he said.

Health officials said that summer and fall are the peak seasons for meningitis and that a smattering of cases in a relatively small geographic area is not unusual.

"Typically, you may or may not hear about [such cases] because they don't end in tragedy or death," said Lucy Caldwell, spokeswoman for the Virginia Department of Health.

"Most times, people do recover. So certainly this is a serious situation. . . . But the best precautions people can take, no matter your age or if you're a student, are to try to keep your immune system healthy, get enough rest . . . wash your hands and do not share drinks, especially this time of year," Caldwell said.

Rather than panicking, people need to be aware of the symptoms, said Kathy Harben, a spokeswoman for the U.S. Centers for Disease Control and Prevention in Atlanta, especially if they know they've had contact with someone who has been ill.

Meningitis is an infection of the fluid that surrounds the brain and the spinal cord. Symptoms include severe headaches, a stiff neck, sensitivity to bright light, drowsiness, confusion, nausea and vomiting. It is spread by direct contact, such as with the saliva or mucus of an infected person.

Viral meningitis is generally less severe than the bacterial form, and most people with healthy immune systems recover fully after a period of rest.

Porterfield said public health officials have assured the school district that the virus is "way low on the scale" of risks to students.

"Viral meningitis is a disease that does not send up red alerts in the Health Department," she said. "We're trying to not create huge panic in this part of the county."

Although bacterial meningitis can be life-threatening, the symptoms of the viral form resolve themselves in most cases, said Denise Sockwell, an epidemiologist with the Virginia Department of Health.

Porterfield, who was monitoring the cases over the weekend, said school officials will keep parents up-to-date.

Anyone who detects symptoms of meningitis should call a physician, officials said.