Bacterial meningitis, a potentially life threatening disease that affects children and adults, is on the decline thanks to required immunizations.
New government research indicates that bacterial meningitis cases have dropped by 31 percent. Immunizations have reduced infections caused by two of the primary germs that cause the potentially devastating infection. With fewer infections in children, older adults are becoming the main hosts of the disease.
“The good news is that fewer people are getting bacterial meningitis. The bad news is that if you get it, it’s still a very serious infection,” said study co-author Dr. Cynthia Whitney, chief of the bacterial respiratory diseases branch at the U.S. Centers for Disease Control and Prevention in Atlanta. ”There are still at least 4,000 cases a year, including about 500 that are fatal,” she added.
According to the Centers for Disease Control and Prevention website, meningitis is an inflammation of the membranes that cover the brain and spinal cord. People sometimes refer to it as spinal meningitis. Meningitis is usually caused by a viral or bacterial infection. Knowing whether the cause of the meningitis is a virus or bacterium is important because the severity of illness and the treatment differ depending on the cause. Viral meningitis is generally less severe and clears up without specific treatment. But bacterial meningitis can be quite severe and may result in brain damage, hearing loss, or learning disabilities. For bacterial meningitis, it is also important to know which type of bacteria is causing the meningitis because antibiotics can prevent some types from spreading and infecting other people.
Symptoms include high fever, headache, and stiff neck in anyone over the age of 2 years. These symptoms can develop over several hours, or they may take 1 to 2 days. Other symptoms may include nausea, vomiting, discomfort looking into bright lights, confusion, and sleepiness. In newborns and small infants, the classic symptoms of fever, headache, and neck stiffness may be absent or difficult to detect. Infants with meningitis may appear slow or inactive, have vomiting, be irritable, or be feeding poorly. As the disease progresses, patients of any age may have seizures.
During the investigation period between 1998 and 2007, the incidence of bacterial meningitis dropped from two cases per 100,000 people to 1.38 cases per 100,000 people. The average age of those affected increased from 30.3 years to 41.9 years.
The incidence of meningitis was highest among blacks and children under 2 months old throughout the study period, the CDC reported.
In addition, rates of death caused by bacterial meningitis didn’t change significantly over the study period. Among adults, those aged 65 or older were most likely to die from the illness.
There are three different types of vaccines available for bacterial meningitis. These vaccines don’t cover every strain that can cause meningitis, but they do offer protection against many of the common strains. The Hib vaccine, which covers H. influenzae, is part of routine childhood immunizations.
The meningococcal vaccine (MCV4), which protects against N. meningitidis, covers against a form of bacterial meningitis that is often passed from person-to-person when many people are living in close quarters, such as a college dormitory or military barracks. The CDC recommends the first dose of this vaccine be given at 11 to 12 years old, and then a booster at 16 years old; it’s also recommended for certain high-risk children aged 2 through 10. If you’re over 16 when you first receive this vaccine, the CDC says only one dose is needed.
The pneumococcal vaccine (called PCV-13 for children and PPSV in adults) is part of routine childhood immunizations. People who are at higher risk of developing bacterial meningitis may receive a booster dose. In addition, people who are over 65, or younger people who have chronic health conditions or a compromised immune system, should also receive this vaccination, as should anyone who smokes or has asthma, despite their age, according to the CDC.
“The good news is that we’re doing something to prevent bacterial meningitis, and we’ve made a lot of strides in the past decade. But, physicians and patients need to know that bacterial meningitis still occurs and it is still a deadly serious infection,” Whitney said.
Besides getting immunized, Whitney noted that staying healthy and not smoking can help keep your immune system primed to fight off these infections. She said it’s also important to note that Listeria is a significant cause of meningitis, and that pregnant women need to be especially careful about the foods that they eat to avoid this infection.
Results of the study are published in the May 26 issue of the New England Journal of Medicine.