MENINGITIS & VACCINES

Meningitis: Inflammation of the meninges (covering) of the brain or spinal cord.  

(The Merck Manual, 16^th edition)

Etiology and Incidence          

Inflammation can be due to infection or irritation. Following is a list of various organisms/conditions that cause meningitis: 

Infectious Meningitis 

• Acute -Bacteria
• Subacute - TB/Syphilis 

• Acute - Virus
• Subacute - Malignancies/Diseases

Bacterial Meningitis & Vaccines

 3 pathogens(organisms) account for 80% of cases of bacterial meningitis: Neisseria meningitidis (meningococcus), Hemophilus influenza type b, and Streptococcus pneumoniae (pneumococcus). 

• Hemophilus influenzae was the most common cause of bacterial meningitis in the United States. Nearly all cases occur in children under 6 years of age.

Vaccine: Hib - against H.influenzae type b. Recommended for children 2 months to 5 years of age. On the Recommended Childhood Immunization Schedule. Mandated.  

• Pneumococcal meningitis (S. pneumoniae*)is the most frequently observed agent in adults over the age of 30 years.     

Vaccine: Pnu-Imune 23 (PPV23) - against S. Pneumoniae (primarily for pneumococcal pneumonia). Recommended for all persons over 65 years of age and younger persons with certain chronic medical problems. Not effective in children under 2 years of age.
Not on Recommended Childhood Immunization Schedule. Not mandated in children.  

Vaccine: Prevnar (PCV) - against S. pneumoniae (primarily for pneumococcal meningitis). Recommended for all infants and toddlers.
On current Recommended Childhood Immunization Schedule. Mandated in many states.

*  {84 different serotypes of Streptococcus pneumoniae  have been identified (Harrison's Principles of Internal Medicine,  13^th edition). Primarily s. pneumoniae causes pneumococcal pneumonia and pneumococcal meningitis but it may also cause endocarditis, otitis media (middle ear infection), mastoiditis,  paranasal sinusitis or conjunctivitis.}  

•  Meningitis due to N. meningitidis is most often encountered in children and young adults and may occur in epidemics.

Vaccine: Menactra - against N. meningitidis (meningococcal). It is currently highly recommended for freshmen college students, especially those living on campus.

Normally recommended for
1. High-risk individuals (immune deficient, asplenic[spleen removed or non-functioning] 
2. Travelers where endemic/epidemic (Sub-Saharan Africa)
3. Persons 2 years of age and above in epidemic or endemic areas.

Not on Recommended Childhood Immunization Schedule. Not mandated. 

Meningococcal Disease in College Students

The following information is from the Centers for Disease Control regarding the modestly increased risk for meningococcal disease among college students, particularly those who live in dormitories or resident halls. The full CDC report can be viewed at http://www.cdc.gov/mmwr/preview/mmwrhtml/rr4907a2.htm 

The full report presents recommendations developed by the Advisory Committee on Immunization Practices (ACIP), regarding the education of students and parents about meningococcal disease and the polysaccharide meningococcal vaccine so that they can make informed decisions regarding vaccination.

The following information is a summary from the CDC report:

Recent studies provide data concerning the risk of sporadic meningococcal disease among college students:

1- 1990-1991-A questionnaire designed to evaluate risk factors for meningococcal disease among college students was sent to 1900 universities, resulting in a 38% response rate. Forty-three cases of meningococcal disease were reported during the 2 years from colleges with a total enrollment of 4,393,744 students, for a low overall incidence of 1.0 per 100,00 population per year. However, cases of meningococcal disease occurred 9-23 times more frequently in students residing in dormitories than in those residing in other types of accommodations. The low response rate and the inability of the study to control for other factors make these results difficult to interpret.

2- 1992-1997 - A retrospective, cohort study conducted in Maryland identified 67 cases among persons aged 16-30 and were identified by active laboratory-based surveillance. Fourteen cases were among students attending Maryland colleges, and 11 were among those in 4-year colleges. The overall incidence rate in Maryland college students was similar to the incidence in the US population of persons the same age. Rates were elevated for students living in dormitories compared with students living off-campus.

3- 1998-1999 - US started to keep track of the disease in college students. In this time period 90 cases were reported to the CDC. These cases represent approximately 3% of the total cases that occur each year in the United States. Eighty-seven cases occurred in undergraduate students, and 40% occurred among the 2.27 million freshman students. Eight students died.

This data suggests that the overall rate of disease among undergraduate college students is lower than the rate among persons aged 18-23 years who are not enrolled in college. Even though the rates were higher in freshmen students (4.6/100,000) living in dormitories, it was still lower than the threshold of 10/100,000 recommended for initiating meningococcal vaccination campaigns.

Fifty of the students were enrolled in a case-control study and the results showed that freshmen living in dormitories were at a higher risk for disease. In addition white race, radiator heat, and recent upper respiratory infection were associated with disease.

The American College Health Association (ACHA) recommends that college health services take a more proactive role in alerting students and their parents about the dangers of the disease and that college students consider vaccination and that colleges and universities ensure that all students have access to a vaccination program for those that want to be vaccinated.

Cost-effectiveness

Nationwide vaccination of freshmen who live in dormitories would result in the administration of 300,000-500,000 doses of vaccine each year, preventing 15-30 cases of disease and one to three deaths per year. The cost per case prevented would be $600,000- $1.8 million at a cost per death prevented of $7 million to $20 million.

Vaccination of all freshmen would result in the administration of 1.4-2.3 million doses of vaccine each year preventing 37-69 cases of disease and 2-4 deaths each year. The cost per case prevented would be $1.4-$2.9 million, at a cost per death prevented of $22 million to $48 million.

These data suggest that for society as a whole, vaccination of college students is unlikely to be cost effective.

Based on the above information the Advisory Committee on Immunization Practices of the Centers for Disease Control made the following recommendations regarding the use of meningococcal vaccine in college students:

· Providers to incoming or current college freshmen, particularly those living in dormitories should inform these students and parents about the disease and the vaccination. ACIP does not recommend that the level of increased risk among freshmen warrants any specific changes in living situations with freshmen.

· College freshmen who want to reduce their risk for meningococcal disease should either be administered vaccine (by a doctor's office or student health service) or directed to a site where vaccine is available.

· The risk for disease among non-freshmen college students is similar to that for the general population. However, the vaccine can be administered to non-freshmen undergraduates who want it.

· Colleges should inform incoming and/or current freshmen, particularly those who plan to live or already live in dormitories or residence halls about meningococcal disease and the availability of the vaccine.

· Public health agencies should provide college and health care providers with information about the disease and the vaccine as well as information regarding how to obtain the vaccine.

NVIC Note: At the present time the CDC has not suggested universal use of this vaccine for college students. The vaccine does not protect against all strains of the disease. There are reported cases of students who have been vaccinated, contract meningitis and die. From a cost/benefit perspective, requiring this vaccine in every state would be very expensive.

Morbidity and Mortality Weekly Report, Recommendations and Reports, Prevention and Control of Meningococcal Disease and Meningococcal Disease and College Students, June 30, 2000.
http://www.cdc.gov/mmwr/preview/mmwrhtml/rr4907a2.htm

The government has created a Vaccine Information Sheet or VIS for this disease. You can view this sheet at: http://www.cdc.gov/nip/publications/VIS/vis-mening.pdf