2. Meningococcal disease
an acute infection caused by Neisseria meningitidis with spray mechanism of
transmission; clinically characterized by lesions of the mucous membrane of
the nasopharynx (nasopharyngitis), generalization in the form of specific
septicemia (meningococcemia) and inflammation of the soft meninges
(meningitis).
Meningitis disease is an infection of the meninges, the membrane covering the
brain. Bacterial meningitis is very serious because its onset is rapid and the
infection is associated with a significant risk of death; it may also result in
mental retardation, deafness, epilepsy, etc. It can be treated with appropriate
antibiotics that also prevents spread.
3. Etiology:
• Neisseria meningitidis is a Gram-negative
diplococcus bacterium.
• There are 12 serogroups of N. Meningitidis that
have been identified, 6 of which (A, B, C, W, X and
Y) can cause epidemics. Geographic distribution
and epidemic potential differ according to
serogroup.
6. Transmission
• Neisseria meningitidis only infects humans; there is no animal
reservoir.
• Person-to-person through droplets of respiratory or throat
secretions from carriers.
• Close and prolonged contact – such as kissing, sneezing or
coughing on someone, or living in close quarters (such as a
dormitory, sharing eating or drinking utensils) with an infected
person (a carrier) – facilitates the spread of the disease.
• The bacteria can be carried in the throat and sometimes, for
reasons not fully understood, can overwhelm the body's defenses
allowing infection to spread through the bloodstream to the brain. It
is believed that 10% to 20% of the population carries Neisseria
meningitidis in their throat at any given time. However, the carriage
rate may be higher in epidemic situations.
10. Meningococcemia
In the first hours of the disease on
the skin of the lower extremities,
the torso appears scant petechial
rash with certain elements of the
star-shaped character (with a
diameter of 2-3 mm, irregularly
shaped, protruding above the
level of the skin, firm to the
touch).
Meningococcemia without meningitis is rare, mainly in
patients hospitalized in the first hours of the disease.
In less severe signs of intoxication mild, the body
temperature of 38-39°C.
11. • In moderate disease the body temperature to
40°C, abundant hemorrhagic rash, petechial
and stellate elements appear on the shins,
thighs, inguinal and axillary areas, abdomen
and chest.
• Elements of the rash may increase in size,
attaining a diameter of 3-7 mm.
• In severe forms of the disease hemorrhagic
dimensions of the elements can be larger - up
to 5 -15 cm or more, with necrosis of the skin.
19. Epidemics of meningococcal meningitis: Every year, bacterial meningitis epidemics affect more than 400
million people living in the 26 countries of the extended "African meningitis belt" (from Senegal to Ethiopia). In this
area over 900 000 cases were reported in the last 20 years (1995–2014). Of these cases, 10% resulted in deaths,
with another 10–20% developing neurological sequelae. The most recent large-scale epidemic in the Belt
occurred in 2009 and affected mainly Nigeria and Niger, causing over 80 000 reported cases. From 2010 to 2014
cases have been steadily decreasing, with approximately 24 000 cases in 2010 to 11 500 cases in 2014.
20. Symptoms
A stiff neck,
High fever,
Sensitivity to light,
Confusion,
Headaches
Vomiting.
Bacterial meningitis may result in brain
damage, hearing loss or a learning
disability in 10% to 20% of survivors.
A less common but even more severe
(often fatal) form of meningococcal
disease is meningococcal septicaemia,
which is characterized by a
haemorrhagic rash and rapid
circulatory collapse.
Even when the disease is
diagnosed early and
adequate treatment is
started, 5% to 10% of
patients die, typically within
24 to 48 hours after the
onset of symptoms.
22. • Culture of the bacteria from specimens of spinal fluid or blood,
• A lumbar puncture: a purulent spinal fluid, the bacteria in microscopic
examinations.
• Agglutination tests or by polymerase chain reaction (PCR).
• The identification of the serogroups and susceptibility testing to antibiotics
are important to define control measures.
Diagnosis
23. Treatment
Appropriate antibiotic treatment must be started as soon as
possible, ideally after the lumbar puncture has been carried
out if such a puncture can be performed immediately.
If treatment is started prior to the lumbar puncture it may be
difficult to grow the bacteria from the spinal fluid and
confirm the diagnosis.
A range of antibiotics can treat the infection, including
penicillin, ampicillin, chloramphenicol and ceftriaxone.
Under epidemic conditions in Africa in areas with limited
health infrastructure and resources, ceftriaxone is the drug
of choice.
