EPIDEMIOLOGY OF MENINGO COCCAL MENINGITIS

1. EPIDEMIOLOGY OF
MENINGOCOCCAL
MENINGITIS
DR. MAHESWARI JAIKUMAR
maheswarijaikumar2103@gmail.com

3. MENINGOCOCCAL MENINGITIS
• Meningococcal meningitis is
also called as cerebrospinal
fever.
• It is an acute communicable
disease caused by Nesseria
meningitidis.

4. • Meningitis usually begins with
intense headache, vomiting and
stiff neck and progress to coma
within a few hours.
• The meningitis is a part of
septicaemic process.

5. • The fatality is about 80%.
• With early diagnosis the case
fatality have declined to 10%.

6. EPIDEMIOLOGICAL
FEATURES

7. AGENT
• The causative
agent,
Nesseria
meningitidis is
a gram
negative
diplococci.

8. • 12 serotypes have been
identified.(A,B,C,29E,H,I,K,L,W13
5,X,Y,Z based on the structure of
the polysaccharide capsule)

9. • The majority of invasive
meningococcal infections are
caused by organisms of
serogroups A,B,C,X,W135.
• N.meningitis is a delicate
organism. It dies rapidly to heat
and cold.

10. SOURCE OF INFECTION
• The organism is found in the
nasopharynx of cases and
carriers.

11. PERIOD OF COMMUNICABILITY
• Until meningoccoci are no longer
present in discharges from and
throat.
• Cases rapidly lose their
infectiousness within 24 hours of
specific treatment.

12. AGE & GENDER
• The disease is predominately the
disease of children.
• Younger groups are more
susceptible than older children.
Both gender are equally infected.

13. IMMUNITY
• Mostly immunity is acquired
through subclinical infection.
• Clinical disease and
immunization confers a life time
immunity.

14. • Infants receive passive immunity
from their mother.

15. ENVIRONMENTAL
FACTORS

16. • Seasonal variation is well
established.
• Outbreaks occur more frequently
in the dry and cold months
(December to June).

17. • Overcrowding (schools, refugee
and other camps) predisposes
individuals to get infected.

18. MODE OF
TRANSMISSION

19. • The disease spreads mainly by
droplet infection.
• The portal of entry is through
the (nasopharynx) respiratory
tract.

20. INCUBATION PERIOD
• Usually 3 to 4 days, but may vary
from 2 to 10 days.

21. CLINICAL COURSE

22. • Most infections do not cause
clinical disease.
• Many infected people become
asymptomatic carriers of the
bacteria and serve as reservoir of
infection.

23. • Meningococcal meningitis has a
sudden onset of intense
headache, fever, nausea,
vomiting, photophobia, stiff
neck and various neurological
signs.

27. • The disease is fatal within 24- 48
hours.
• Even with prompt antimicrobial
treatment in good health care
facility, permanent neurological
squealae may be seen (5 to 10 %
cases).

29. • In meningococcal septicaemia,
there is a rapid dissemination of
bacteria in the blood stream.
• The less common meningococcal
disease, is characterized by
circulatory collapse, hemorrhagic
skin rash and high fatality rate.

31. PREVENTION AND
CONTROL

32. CASES
• Treatment with antibiotics can
save lives of 95% provided that
the treatment is started within
the first two days of illness.
• Penicillin is the drug of choice.

33. • In penicillin allergic patients,
ceftriaxone and other third
generation cephalosphorins
should be substituted.
• A single dose of long acting
chloramphenicol or cetriaxone is
used for treatment of epidemic
in sub Saharan Africa.

34. • Septicaemic shock and raised
intracranial pressure in
meningitis are particular
problems in the management of
the disease.

35. CARRIERS
• Treatment with penicillin does
not eradicate the carrier state;
more powerful antibiotics such a
rifampicin are needed to
eradicate the carrier state.

36. CONTACTS
• Close contacts are at risk of
developing the disease.
• Antibiotics are effective in
preventing additional cases
through eradicating carriage of
the invasive strain.

37. MASS CHEMOPROPHYLAXIS
• Mass chemoprophylaxis is
restricted to medically
supervised communities.
• The drugs of choice are
CIPROFLOXACIN, MINOCYCLINE,
SPIRAMYCIN and CEFTRIAXONE.

38. VACCINE
• Currently available
meningococcal vaccines include
POLYSACCHARIDE vaccines and
POLYSACCHARIDE-PROTEIN
CONJUGATE VACCINES.

39. POLYSACCHARIDE VACCINE
• Internationally marketed
meningococcal polysaccharide
vaccines are available in bivalent
(A,C), trivalent (A,C,W 135) and
quadrivalent(A,C,W135, Y)
formulations.

40. • The vaccines contain 50
microgram of each of the
individual polysaccharides.
• The vaccine is administered as a
single dose to persons > 2 years
old through subcutaneous route.

41. • Adverse reactions to vaccine are
usually mild.
• Most frequent reaction is 1-2
days of pain and redness at the
site of injection, and transient
fever.

42. CONJUGATE VACCINES
• Licensed meningococcal conjugate
vaccines are monovalent (A or C)
or quadrivalent (A,C,W135,Y) and
also include a combination
vaccine based on H.influenza type
b and N.meningiditis serogroup C
vaccines (HibMenC)

44. • Conjugate vaccine should be
given as intramuscular injection,
preferably in the deltoid muscle
(or in the anterolateral aspect of
the upper thigh in children < 12
months of age)

45. • Meningococcal vaccines should
be stored at 2-8 degree
centigrade.
• Conjugate vaccines are preferred
over the polysaccharide vaccines
due to their potential for herd
protection and increased
immunogenicity.

46. THANK YOU