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Clinical description: Meningitis
• Meningitis is a disease caused by inflammation of the
protective membranes covering the brain and spinal cord
known as the meninges.
• The inflammation is usually caused by an infection of the
fluid surrounding the brain and spinal cord. Meningitis is
also referred to as spinal meningitis.
• Can be Viral Or Bacterial
• Meningococcus Meningitis (Neisseria meningitidis )
• Leading cause of bacti meningitis in children in US and other parts
of works
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Causes of Meningitis
• Bacterial
• Viral
- Meningococcus
- Neisseria meningitidis
- Arboviral (mosquitoborne) diseases
- Influenza
- LaCrosse Encephalitis
virus
- West Nile Virus
- Also enteroviral
Haemophilus influenzae
- Listeria
- Mumps
- Pneumococcus
- Group A Streptococcus
- Group B Streptococcus
4. HISTORY of Meningococcal meningitis
• 1805 1st described in Sweden by Vieusseaux ;
called episodic cerebrospinal fever.
• Throughout 19th century, episodic fever cases
, mostly among children and military recruits.
• 1887, bacterium isolated from cerebrospinal
fluid (CSF) in 6 fatal cases by Weichselbaum
• originally named Neisseria intracellularis.
• 1893, lumbar puncture technique for collecting
CSF, making DX of meningococcal disease
possible
• early 1900s 1st tx for meningococcal disease German & U.S. scientists developed anti-sera
that could be injected intrathecally (directly into
cerebrospinal space)
• Resulted in mortality rate decreased to 25 %.
• However serum sickness & 2ndry meningitis
inhibited utility
• Around WW 1 Preliminary vaccine trials
began, led to major vaccine trails in 20th
century, now have a vaccine for 2 types
5. Neisseria Meningitidis
• N. meningitidis is Diplococci meaning that it is spherical in shape and
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pairs together
Aerobic- breaths oxygen
Lives in mucous membranes in the nose a throat.
spread through the exchange of respiratory and throat secretions (i.e.,
coughing, kissing).
--not spread by casual contact or by simply breathing the air where a
person with meningitis has been.
6. Epidemiology – U.S.
• Carried by 5%-10% of population
• 3000 people in the United States become infected with the bacteria, and as many
as 1 in 10 of those people die.
• Common among college freshman and Military recruits
• Both have several common characteristics (e.g., age, diverse geographic backgrounds, crowded
living conditions).
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97% of cases sporadic (background endemic disease), 3% outbreaks
Seasonal – peak in December/January
Highest rate of disease among infants <1 yr of age (9.2/100,000 from 1992-2001)
Louisiana has some of highest
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8. Meningococcal Disease Worldwide
• Incidence likely exceeds 100,000 cases/yr
• Majority are epidemics within the meningitis belt
• Worldwide, endemic disease 1-5/100,000
• Sub-Saharan Africa, approaches 20/100,000
9. Serotypes of MD
• Almost all MD in US due to serogroups B, C, Y
• Africa and Asia, mostly groups A, C
• In infants, >50% of cases are serogroup B* (>70% in 2005)
• In patients > 11 yrs of age, 75% caused by C, Y or W-135
• * B = no vaccine
10. Risk Factors
• Military recruits
• College students, especially freshmen in dorms
• Travel to endemic area, sub-Saharan Africa,
Saudi Arabia during the Hajj
• Terminal complement component deficiency
• Recent URI
• Active/passive smoking
• Microbiology techs
11. MD and the Military
• WWI: 150 cases/100,000 troops per year w/
39% mortality
• greatest # of cases occurred during winter months and was
assoc. w/ over-crowding of military barracks.
• disease rates remained high despite disease control efforts:
using prophylactic nasal sprays, spacing between beds,
sequestering of troops,.
• Pre 1971, MD rates elevated among U.S.
military recruits.
• Outbreaks frequently followed large-scale
mobilizations
• Recruits in initial training camps at substantially
> risk for disease than regular troops
• 1964--1970, rate of hospitalizations resulting
from MD among all active duty service
members : 25.2 per 100,000 person- years
• This led to development of MD vaccines
• Field trials of group C polysaccharide vaccine
among U.S. Army recruits demonstrated an
89.5% reduction in rate of serogroup C versus
nonvaccinated recruits
12. MD and the Military
• Beginning in October 1971, all new
recruits were vaccinated with group C
vaccine
• Cannot attribute decline in disease
entirely to vaccine: other measures taken
to decrease transmission such as:
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Head-to-toe sleeping
Reduced crowding in barracks
Cohorting
Aggressive treatment and ppx with antibiotic
• Now rates of MD remain low in military,
large outbreaks no longer occur.
• During 1990--1998, overall rate of
hospitalizations from MD among
enlisted, active-duty service members
was 0.51 per 100,000 person-years
• ~ 180,000 military recruits receive a
single dose of meningococcal vaccine
annually.
• Revaccination only indicated when military personnel
traveling to countries in which N. meningitidis is
hyperendemic or epidemic
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Meningitis Symptoms can be the same for
Viral and Bacterial
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Headache
Fever
Vomiting
Photophobia
Lethargy
Neck stiffness
Rash (more than 50% of cases)
Seizures (20% of patients at presentation
and an additional 10% of patients within 72
hours)
• Early nonspecific symptoms (especially in
infants):
S/S of MD meningitis can appear
quickly or over several days. Typically
they develop within 3-7 days after
exposure.
s/s vary may include :
• Nonspecific prodrome of cough,
headache, and sore throat
• After a few days of upper
respiratory symptoms, rising
temperature, often after a chill
• Malaise, weakness,, headache,
nausea, vomiting, and arthralgias
(joint pain)
• Neck pain (touch chin to chest)
• Skin rash (characteristic
manifestation of meningococcemia),
often rapidly progressive
Glass test: ordinary glass placed on rashaffected skin of a patient and rolled for a
while. If the bright red spots do not
undergo a color change then patient is
possibly affected with meningitis
15. Complications of MD
• Bloodstream infection (Septicemia or
bacteremia)
• Purpura fulminans severe complication of
meningococcal septicaemia.
• Appears in 15-25% of people with MD
• presents as a petechial rash spreading
rapidly in extent and depth, evolving into fullthickness skin necrosis.
• Can be fatal.
• In fatal cases, deaths can occur in as little as a
few hours.
• In non-fatal cases, permanent disabilities can
include hearing loss and brain damage
• Needs early aggressive tx w/ antibiotics
• Even with tx may have disfigurement,
amputation, death
• About 11 % of people of any age who are infected
will die, even with appropriate tx .
• Among adolescents & young adults, case fatality
rate is 10 - 14%.
• Up to 19 % of survivors have permanent damage,
such as hearing loss, brain damage, kidney,
amputations
4 month old female with
gangrene of hands and
lower extremities due to
meningococcemia.
17. DX Meningococcal meningitis
• Physical findings : Pain and resistance
to neck flexion, other signs of
meningeal irritation, petechiae, fever
(variable intensity)
• Lab findings in early stages of
meningococcal disease are
nonspecific and often unremarkable.
• Definitive diagnosis requires culture of
meningococci from blood,
cerebrospinal fluid, joint fluid, or skin
lesions.
• Quick medical attention is extremely
important if meningococcal disease is
suspected.
19. Meningococcal Vaccines
• 2 vaccines available in US .
• Menomune/MPSV4 (Meningococcal polysaccharide vaccine)
• 85-100% effective at preventing subtypes A,C,Y, and W-135.
• does not protect against subgroup B. The protection offered is
short term. – need booster
• Safe for ages > 2
• Serogroups A, C, Y, W135
• Menactra/MCV4 (meningococcal conjugated vaccine)*
• Ages 11-55
• Conjugated with diphtheria toxin variant
• Serogroups A, C, Y, W135
It is been difficult to develop an effective vaccine for serogroup B.
Meningococcal B vaccines exist but more tests are needed to
determine the safety and effectiveness.
* req. for Tulane dorm residents
20. Who should get MCV4?
CDC’s Advisory Committee on Immunization Practices
(ACIP) recommendations
• Routine vaccination to adolescents aged 11 - 18 years
• single dose of vaccine @ age 11 or 12 years, w/ booster dose @
age 16 for persons who receive 1st dose before age 16 years
• Persons aged ≥2 months at increased risk for
meningococcal disease should also be vaccinated, :
• Persons with certain medical conditions such as anatomical or
functional asplenia (absence of normal spleen function )
• Special populations such as unvaccinated or incompletely
vaccinated first-year college students living in residence halls,
military recruits, or microbiologists with occupational exposure
• Persons aged ≥9 months who travel to or reside in countries in
which meningococcal disease is hyperendemic or epidemic,
particularly if contact with the local population will be prolonged.
21. MD vaccine and college students
• September 30, 1997, American College Health
Association (ACHA), which represents about half of
colleges that have student health services, released a
statement recommending that "college health services
[take] a more proactive role in alerting students and their
parents about the dangers of meningococcal disease,"
that "college students consider vaccination against
potentially fatal MD ," and that "colleges and universities
ensure all students have access to a vaccination program
for those who want to be vaccinated"
• Varies by state
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Prevention
• Keeping up to date with recommended
immunizations is the best defense.
• Good hygiene.
• Rifampin, ceftriaxone, and ciprofloxacin are
appropriate drugs for chemoprophylaxis in adults.
The drug of choice for most children is rifampin.
• Chemoprophylaxis may be administered in
conjunction with vaccinations.