Acute And Chronic Meningitis Health Article

Prevention

The most effective prevention for bacterial meningitis is provided by vaccination. This has been most impressively documented with H. influenzae type b, for which the new conjugated vaccines have led to a reduction of more than 90% in the number of cases in vaccinated populations. ¹ Current recommendations are to vaccinate all children against H. influenzae type b with one of several available vaccines, beginning at 3 months of age. Unfortunately, this is not possible in many countries for economic reasons.

A 23-valent polysaccharide vaccine and newly developed conjugate vaccines are available for vaccination against invasive pneumococcal disease, including meningitis. ⁶⁶ The polysaccharide vaccine, which is cheaper and covers more serotypes than the currently available conjugate vaccines, should be offered to adults at increased risk for invasive pneumococcal infections, such as the elderly and those with underlying disease, including immunocompromising conditions, asplenia, sickle-cell disease and anatomic defects predisposing to meningitis. Some countries, including the USA, have adopted recommendations to routinely vaccinate all children under 24 months of age with the conjugate vaccine. ⁶⁷ Older children at increased risk for invasive diseases should also be immunized with a conjugate pneumococcal vaccine.

In the case of meningococcal meningitis, polysaccharide vaccines are available for all major serotypes except group b, which has a poorly immunogenic capsule. For group c, new conjugate vaccines that are highly immunogenic in children under the age of 2 years have recently been licensed. Vaccination against meningococci is currently recommended for children and young adults in some countries in the setting of ongoing epidemics and for travelers to countries with high endemic infection rates. ⁶⁷

Although no vaccines to prevent transmission of group B streptococci from colonized mothers to their newborn are yet available, preventive strategies using antibiotics have been widely implemented and have substantially reduced the risk of group B streptococcal infections in neonates. Typically, intrapartum administration of penicillin is offered to women who have been shown to be colonized with group B streptococci before delivery, to women who have risk factors for neonatal infection (prematurity, prolonged rupture of the membranes, signs of infection during labor) or to both groups. A recent study suggests that screening with subsequent intrapartum treatment of colonized women may be the preferred approach. ⁶⁸

Antibiotics are widely used for the prevention of meningitis associated with neurosurgery and the placement of intraventricular shunts. In patients undergoing craniotomy, perioperative antibiotic prophylaxis appears to reduce the number of postoperative infections. Studies examining the effect of periprocedural or prophylactic antibiotics in patients receiving various types of intraventricular shunts or intracranial pressure monitors have not consistently shown a benefit. In some cases, prophylactic antibiotics have been associated with infections caused by difficult-to-treat organisms, such as methicillin-resistant Staphylococcus aureus (MRSA) and fungi. Given the increasing problems with resistant organisms and the diagnostic problems caused by prophylactic antibiotics in patients who have suspected device-associated infection, it seems preferable to refrain from routine use of long-term prophylactic antibiotics in these patients. ⁴³