WASHINGTON — Fever, chills, vomiting: It starts like a stomach bug or the flu. But bacterial meningitis can go on to kill terrifyingly fast — one of the few infections in the U.S. in which someone can feel fine in the morning and be dead by night. And prime targets are tweens, teens and college freshmen.

Amid all the publicity about children's flu shots this year is quiet concern that vaccination against meningococcal meningitis not fall by the wayside, just as doctors are charting some progress against the rare but devastating infection.

In the two years since the government recommended that every adolescent be vaccinated, close to 40 percent of tweens and teens are, said Dr. Carol Baker, a pediatric vaccine specialist at Baylor College of Medicine.

That's a decent start considering parents seldom hear about the illness. It affects only about 2,000 Americans a year, with rates recently inching down to historic lows.

But about 15 percent of the people who catch this fast-moving germ die — and one in five of the survivors suffer permanent disabilities including brain damage, deafness or amputated limbs.

"What hasn't changed is the severity," warned Baker.

There are multiple types of meningitis, an infection of the membranes around the brain and spinal cord. Viral types tend not to be as severe.

The Hawai'i Department of Health encourages parents of children ages 11 and 12 to get their kids vaccinated. Incoming college freshmen who live in dormitories also should be vaccinated.

Lisa Mendez, chief of the department's Immunization Branch, said the state does not know how many in these age groups are being immunized, but said, "I'm sure there's room for improvement."

She added that there haven't been recent deaths from meningococcal meningitis in Hawai'i.

Baker worries about an uptick in meningococcal infections this fall and winter, especially as attention to the new swine flu and predictions of a busy influenza season in schools overshadow meningitis campaigns. A prior bout of flu can make people more susceptible to catching the infection.