1

Meningococcal Meningitis

Dr Rajkumar PatilProfessor, Community Medicine

MGMCRI, Pondicherry

2

Learning objectives

At the end of the class student should be able to:• Describe the epidemiological factors of

Meningococcal Meningitis• Describe the prevention of influenza

Meningococcal Meningitis

3

Introduction and burden of Meningococcal Meningitis

• Meningococcal meningitis is a bacterial form of meningitis, a serious infection of the thin lining that surrounds the brain and spinal cord.

• Caused by N.meningitidis

• During the 2014 epidemic season, 19 African countries reported 11908 suspected cases including 1146 deaths

• During 2011 in India: 6629 cases,464 deaths (Andhra,WB,Odisha,MP,Jharkhand,TN,

Karnataka,Assam, Delhi,UP)

4

5

The extended meningitis belt of sub-Saharan Africa, stretching from Senegal in the west to Ethiopia in the east (26 countries),

has the highest rates of the disease:

• Benin, Burkina Faso, Burundi• Cameroon, Central African Republic, Chad, Côte

d’Ivoire, Democratic Republic of Congo • Eritrea, Ethiopia• The Gambia, Ghana, Guinea, Guinea Bissau • Kenya, Mali, Mauritania, Niger, Nigeria, Rwanda, • Senegal, South Sudan, Sudan, Tanzania, Togo and

Uganda.

6

What is epidemic of Meningo. Meningitis in African belt?• >100 cases per 100,000 population per year

What is endemicity level of Meningo. Meningitis in other countries?>10 cases per 100,000: High2-10: Moderate<2: Low

7

Agent

• Neisseria meningitidis - large epidemics.

• 6 out of 12 serogroups of N. meningitidis (A, B, C, W135, X and Y) can cause epidemics.

• In Africa - Group A most imp.

8

Host

• Age: Children and young adults, highest in 3-12 months infants

• Sex: Both

• Immunity: Susceptibility decreases by age, Immunity acquired by subclinical(mostly),clinical disease or vaccination

9

No animal reservoir

Environmental factors

• dry season between Dec. to June, dust winds, cold nights and upper respiratory tract infections combine to damage the nasopharyngeal mucosa,

• overcrowding • large population displacements due to pilgrimages and

traditional markets. • Low SES• N.Meningitidis dies rapidly on exposure to heat or cold.

Incubation Period: Range 2-10 days, Average 4 days

10

Transmission Droplets of respiratory or throat secretions from mostly

carriers.

Close and prolonged contact – such as kissing, sneezing or coughing on someone.

Living in close quarters (such as a dormitory, sharing eating or drinking utensils) with an infected person (a carrier)

10% to 20% of the population carries Neisseria meningitidis in their throat at any given time.

11

Period of communicability

• If treatment is given- transmission stops within 24 hours

• If not- as long as the organism is in secretion

12

Clinical features • Asymptomatic mostly

• Stiff neck, high fever, sensitivity to light, confusion, intense headache and vomiting.

• Bacterial meningitis may result in brain damage, hearing loss or a learning disability in 10% to 20% of survivors.

• Meningococcal septicaemia: A less common but often fatal form of meningococcal disease is characterized by a haemorrhagic rash and rapid circulatory collapse.

13

14

Case fatality: • If not treated: 50% • 5% to 10% : when the disease is diagnosed early

and adequate treatment is started.

15

Diagnosis• Clinical examination and Lumbar puncture showing a purulent

spinal fluid.

• Microscopic examination of spinal fluid: bacteria can sometimes be seen.

• Growth of the bacteria from specimens of spinal fluid or blood,by agglutination tests or by polymerase chain reaction (PCR).

• The identification of the serogroups and susceptibility testing to antibiotics are important to define control measures.

16

17

Treatment• Medical emergency: Treat as soon as possible, ideally after the

lumbar puncture has been carried out if such a puncture can be performed immediately.

• Appropriate antibiotic within 2 days

(penicillin/ampicillin/chloramphenicol/ceftriaxone)

• Usual DOC: Penicillin

• Under epidemic conditions in Africa in areas with limited health infrastructure and resources, CEFTRIAXONE is the drug of choice.

18

Treatment

• Carriers: Rifampicin

• Contacts:Treatment within 24 hours of identification of index case,Rifampicin,ciprofloxacin,ceftriaxone,Azithromycin

• Mass chemoprophylaxis:Under supervision ciprofloxacin, ceftriaxone,micocycline

19

Prevention

• Meningococcal polysaccharide vaccines: bivalent (groups A and C), trivalent (groups A, C and W), or tetravalent (groups A, C, Y and W)

• Conjugate vaccines:• Since 1999, meningococcal against group C have been available and

widely used.

• Tetravalent A, C, Y and W conjugate vaccines

20

MenA conjugate vaccine-Advantages

• It induces a higher and more sustainable immune response against group A meningococcus.

• It reduces the carriage of the bacteria in the throat .• Long-term protection • Lower price than other meningococcal vaccines (0.50 USD per dose)• Expected to be particularly effective in protecting children under two

years of age, who do not respond to conventional polysaccharide vaccines.

• Thermostable• It is planned that all 26 African countries considered at risk for

meningitis epidemics and targeted by this vaccine introduction programme will have introduced this vaccine by 2016.

21

Outbreak trends

Epidemics due to N. meningitidis serogroup A are disappearing due to the MenA conjugate vaccine.

Other meningococcal serogroups such as NmW, NmX and NmC still cause epidemics albeit at a lower frequency and smaller size.

22

23

Travel Precautions

• If meningococcal vaccination is recommended or required, it should be received at least one week before departure if possible.

24

Thank You