December 1988, Revised March 1997
Introduction
The organism, Neisseria meningitidis, is a Gram-negative diplococcus
that causes meningococcal disease. Invasive meningococcal disease
refers to N. meningitidis infection in the blood (meningococcemia),
in the cerebral spinal fluid (CSF) (meningitis), or from any normally
sterile body site, such as the lung or a joint. Historically,
N. meningitidis has created high mortality epidemics throughout
the world, and death rates have exceeded 50%.
The development of antibiotics has significantly reduced but
not eliminated mortality caused by this organism. It is estimated
that fatality rate with early diagnosis and prompt medical treatment
should be less than 10%.
Infection with N. meningitis may give rise to a variety of clinical
symptoms. The most frequent type of infection from this organism
is an asymptomatic illness of the oro- or nasopharynx. In the
most severe cases, individuals develop overwhelming septicemia
and may die within two to eight hours of initial symptoms.
The variability in clinical symptoms is due to the number of
the bacteria present, the organs that become infected, possibly
the infective strain, as well as other contributing factors. Meningococcal
disease most often occurs in children less than five years of
age; 45% of cases occur in children 2 years and under.
The most common systemic manifestation of meningococcal disease
is meningitis. Individuals who develop acute illness from N. meningitidis
often manifest a sudden onset of fever, intense headache, nausea
and often vomiting, meningismus, and frequently a . Occasionally,
meningococcemia occurs when N. meningitidis enters the blood stream
through the respiratory epithelium. When this happens, invasive
disease may occur without simultaneous infection of the meninges.
Meningococcemia should be suspected in individuals with an unexplained
febrile illness associated with a non-blanching petechial rash
and leukocytosis. Other illnesses resulting from infection from
N. meningitidis include pneumonia, pericarditis, and arthritis.
In addition to early diagnosis and treatment of meningococcal
cases, prompt public health attention is required to eliminate
spread of the disease. Effective prophylactic treatment is available
for contacts to cases of this disease.
The incidence rate for meningococcal disease cases is 1-1.5 per
100,000 population per year for sporadic cases. In Maryland's
population of approximately five million 30-60 cases occur per
year. Persons who are close contacts of people with meningococcal
disease have a significantly greater risk of developing disease
from this organism.
According to the Centers for Disease Control and Prevention,
the attack rate of meningococcal disease of household contacts
exposed to patients who have sporadic meningococcal disease has
been estimated to be 4 cases per 1,000 household contacts exposed
per year, which is 500-800 times greater than for the total population.
Because of this elevated rate, prophylactic antibiotics are given
to contacts.
Asymptomatic colonization of the upper respiratory tract is frequent
(5-20%) and provides the focus from which the organism is spread.
N. meningitidis is transmitted by direct contact with secretions
from the nose and throat, and via respiratory droplets from the
nose and throat of an infected individual.
Indirect transmission, such as through fomites, is insignificant.
The incubation period ranges from approximately 2 to 10 days,
but averages 3 to 4 days. Infected individuals are communicable
until meningococci are no longer present in the discharges of
the nose and mouth. The period of communicability of the meningococcus
prior to acute illness is not well-established.
Limited studies suggest that the majority of cases are infectious
to others for only hours or a few days prior to the onset of symptoms.
Based on these data, the period of asymptomatic transmission by
those with acute illness is likely to be less than 10 days.
In contrast, chronic nasopharyngeal carriers, the principle reservoir,
remain asymptomatic and are protected from acute illness by serum
antibodies. Outbreaks have occurred in child care centers, nursery
schools, colleges, and military recruit camps.
Currently, N. meningitidis serogroups B and C are responsible
for the majority of cases in the United States. Serotypes 2b and
15 are associated with serogroup B disease. Other serogroups,
such as, groups A, X, Y, Z, 29-E and W-135 have also been shown
to be associated with invasive meningococcal disease. Group A
meningococci are found most frequently in outbreaks outside of
the United States.
Diagnosis of invasive meningococcal disease is confirmed by the
isolation of meningococci from blood, from CSF, or from other
normally sterile body fluids, such as synovial fluid or pericardial
fluid. Skin scrapings of petechiae may also yield positive cultures.
Procedures for
Investigation
A. CDC Case Definitions Clinical description Meningococcal
disease presents most commonly as meningitis and/or meningococcemia
that may progress rapidly to purpura fulminans, shock, and death.
However, other manifestations may be observed. Laboratory criteria
for diagnosis Isolation of Neisseria meningitidis from a normally
sterile site
Case classification
Probable: a positive antigen test in cerebrospinal fluid
or clinical purpura fulminans in the absence of a positive blood
culture
Confirmed: a clinically compatible case that is culture
confirmed Comment Antigen test results in urine or serum are unreliable
for diagnosing meningococcal disease.
Comment: Antigen test results in urine or serum are unreliable
for diagnosing meningococcal disease
B. Case Investigation
1. Complete the following REQUIRED REPORTS:
-
Maryland Confidential Morbidity Report (DHMH-1140)
- National Bacterial Meningitis and Bacteremia Case Report form
(CDC 52.15 Rev. 02-93 version preferred) (see Attachment 1). Refer
to the DHMH MERSS Manual for a copy of the form.
NOTE: Because N. meningitidis is one of the organisms
that is monitored by Maryland's Bacterial Invasive Disease Surveillance
(BIDS) System/Emerging Infections Program, the hospital infection
control practitioner may have already completed the morbidity
report and the CDC form.
2. Report the case immediately by telephone to DHMH, Epidemiology
and Disease Control Program, Division of Communicable Disease
Surveillance at 410-767-6712. If DHMH receives the first report,
we will fax the report to the local health department.
3. Assure that the N. meningitidis isolate is sent to the DHMH
laboratory for serogroup determination:
DHMH, Laboratories Administration
201 West Preston Street P.O. Box 2355
Baltimore, MD 21203
4. Enter into MERSS (see Section A for Case Definitions) Mail the
completed Maryland DHM H-1140 and CDC 52.15 forms to:
DHMH, Office of Epidemiology and Disease Control Programs,
Unit #111 Division of Communicable Disease Surveillance
201 W. Preston Street
Baltimore, MD 21201-2323
5. Determine whether the case has been treated to eliminate nasopharyngeal
carriage of N. meningitidis, i.e., determine if the case received
rifampin or another medication listed in Tables 1 and 2, in addition
to medication prescribed to treat acute illness.
6. Occasionally a person without meningococcal disease will be
reported as having a throat culture positive for N. meningitis.
In this situation, no treatment of the individual or contacts is
warranted. No case form, morbidity card or MERSS report is needed.
C. Contact Investigation and Recommendations for Chemoprophylaxis
1. Definition of contacts
Contacts are individuals who have had close contact with a case
at some point during the period 10 days prior to the onset of illness
in the case to 24 hours after the start of antibiotic treatment
in the case. Contact is presumed to have occurred among:
- household contacts (people who have stayed in the same household
with the case)
- child care contacts (children, employees, and volunteers in
the same classroom as a case in institutions, such as group child
care centers, family child care homes, or nurseries) and
- other contacts (such as classmates, other child care contacts,
friends, sexual partners, nurses, respiratory therapists, emergency
medical personnel, etc.) who have been directly exposed to the
case=s oral secretions through sharing food or beverages, kissing,
mouth-to-mouth resuscitation, intubation, suctioning, etc.
2. Procedure for investigating contacts
a. The contact investigation should be conducted promptly. Ideally,
prophylaxis should be started within 24 hours after the diagnosis
of the case.
b. Identify all people who were contacts during the time period
from 10 days prior to the onset of illness in the case to 24 hours
after the start of antibiotic treatment of the case. Obtain information
about contacts, including the time and type of exposure, and record
it on the Contact Investigation Form (see Attachment 2).
c. Advise contacts to do the following as soon as possible:
- Obtain appropriate chemoprophylaxis. Because the typical
incubation period is 2-10 days, efforts to administer chemoprophylaxis
are typically stopped 14 days after the case's onset date. It
is considered to be of little value to administer chemoprophylaxis
14 days or more after the case's onset date. Local health departments
may refer contacts to their private physician or dispense prophylactic
antibiotics directly. See Table
1 and Table 2 for
dosing schedules of recommended antibiotics.
- Undergo an immediate medical evaluation in the event that
they develop febrile illness in the 14 days following the occurrence
of a case, and report the exposure to their medical care provider
when evaluated.
d. Educate contacts. Consider distributing the Meningococcal
Disease Fact Sheet to contacts (See
Attachment 3)
e. In the setting of a child care facility (e.g., group child
care center, family child care homes, or nursery) where contacts
have been identified and can be notified within 10 days of when
the case occurred:
- Request that the administrator of the facility make a list
of the names of all children and employees who are contacts
of the case.
- Recommend prophylaxis for contacts. Consider giving a letter
(see Attachment 4 for
a sample letter) with the Meningococcal
Disease Fact Sheet (and
Rifampin Fact Sheet if Rifampin is used) (see Attachment
3 and Attachment 6) to each contact and to the parent(s)
of each child who was a contact.
- Alert the staff to be observant for children who develop high
fever, rash, irritability, behavioral changes, stiff neck, body
aches, chest pain, or breathing difficulty. Any child who develops
any of these symptoms must be seen by a doctor immediately.
- Immediately report any other child who is diagnosed as having
meningococcal disease to the local health department.
f. In the setting of a school (e.g., elementary, middle, high,
college) where contacts have been identified and can be identified
within 10 days of when the case occurred, consider sending a letter
to inform parents and/or students of the occurrence. Possible
recipients may include persons in the classroom, selected grades,
the whole school, team members, dormitory residents. A sample
letter for schools is attached (Attachment
5). (In the U.S., measures that have not been recommended
for controlling serogroup C outbreaks include restricting travel
to areas with a serogroup C outbreak, closing schools or colleges,
or cancelling sporting or social events (Reference
5, Page21). Consult may be sought from EDCP Division of Outbreak
Investigation.
g. Notify the Office of Epidemiology and Disease Control Programs,
Division of Outbreak Investigation, (410) 767-6677, of
any secondary invasive meningococcal cases.
3. Recommendations for Antimicrobial Chemoprophylaxis of Contacts:
Current recommendations regarding chemoprophylactic treatment of
contacts exposed to a confirmed or probable case of N. meningitidis
are as follows:
- Ideally, prophylaxis should start within 24 hours after diagnosis
of the case.
- Treat contacts prophylactically if N. meningitidis is isolated
from the case's blood, CSF, or a normally sterile site regardless
of the presence or absence of symptoms in the case (i.e., confirmed
case).
- Treat contacts prophylactically if there are findings which
support the diagnosis of meningococcal disease in the case (e.g.,
the detection of polysaccharide antigen by counterimmunoelectrophoresis
or latex agglutination, the detection of gram-negative diplococci
by microscopy, or purpura fulminans) in the absence of a bacteriological
isolate of N. meningitidis (i.e., probable case).
- In situations where the bacterial isolate of the case is not
from a sterile site and the case exhibits upper or lower respiratory
symptoms (e.g., pneumonia), discuss with the case physician whether
N. meningitidis is the primary cause of illness in order to determine
appropriate recommendations for prophylaxis. Treat contacts if
the physician believes the illness is due to N. meningitidis (i.e.,
confirmed case).
- Do not treat contacts prophylactically if N. meningitidis has
been isolated from the throat or nasopharynx of a person who does
not have symptoms of invasive disease (i.e., colonized person,
carrier).
- It is not necessary to obtain throat cultures from contacts.
Chemoprophylaxis should be given to contacts immediately and should
not be delayed while waiting for the results of contacts' throat
cultures.
- If agents other than rifampin, ciprofloxacin, or ceftriaxone
are used in the treatment of meningococcal disease in the case,
the case should receive one of the recommend prophylactic agents
before discharge from the hospital in order to reliably eradicate
nasopharyngeal carriage of N. meningitidis.
Prophylactic antibiotics and dosing are outlined in Tables 1 and
2. Rifampin is the traditional drug of choice for prophylaxis, however,
ciprofloxacin and ceftriaxone now are considered to be reasonable
alternatives (Table 1). Sulfadiazine
is recommended when an isolate is known to be sulfa-susceptible
(Table 2)
Persons taking rifampin should be advised of potential side effects,
such as, orange coloration of urine, stool, and tears. Additionally,
individuals wearing soft contact lenses should not wear their lenses
during the course of rifampin use and for 48 hours after the last
dose. Individuals using oral contraceptives should be advised to
use additional methods of birth control during that cycle (see Attachment
5).
Pregnant women should consult their doctors regarding recommendations
for prophylactic treatment; ceftriaxone is the drug of choice if
prophylaxis is needed.
Meningococcal Vaccine
In the United States, a quadrivalent meningococcal polysaccharide
vaccine is available which stimulates immune responses to serogroups
A, C, Y, and W-135. This vaccine is not routinely administered
to civilians because of limitations in efficacy among children
under 2 years of age and uncertainties about the duration of effect.
The vaccine is recommended, however, for use in controlling outbreaks
of group C meningococcal disease involving older children and
adults. The efficacy of the vaccine in outbreaks caused by other
serogroups is unknown. If used to elicit short-term protection
against group A meningococcal disease, it may be used in children
as young as 3 months of age [Reference 5,
page 3]. Meningococcal vaccine is not indicated in outbreaks of
serogroup B since serogroup B is not covered by the vaccine.
Antimicrobial chemoprophylaxis remains the primary preventive
measure among contacts (defined in Item B.1.
above) and should be administered regardless of plans for vaccine
use. Seven to 10 days are needed following vaccination to develop
protective levels of antibody. Specific recommendations for vaccine
use in outbreak control (when the attack rate exceeds 10 cases
per 100,000) should be made in consultation with the Division
of Outbreak Investigation, EDCP, (410) 767-6677, who will refer
to the ACIP Guidelines [Reference 5] and will
contact the Centers for Disease Control and Prevention for advice.
Table 1: Antibiotics recommended for
chemoprophylaxis and eradication of nasopharyngeal carriage
of N. meningitidis.
Table 2. Sulfadiazine dosages for
use in chemoprophylaxis where isolate is susceptible to sulfa
drugs.
Download Refampin Fact Sheet and Sample Letter
Reference
- American Academy of Pediatrics, Committee on Infectious Diseases
Report of the Committee on Infectious Diseases (23rd ed.) Elk
Grove Village, IL 1994.
- American Public Health Association.. Control of Communicable
Diseases Manual (16th ed.). Washington, DC 1995.
- Centers for Disease Control and Prevention. Case Definitions
for Public Health Surveillance. Morbidity and Mortality Weekly
Report 1990; 39 (No. RR-13).
- Centers for Disease Control and Prevention. Laboratory-based
surveillance for meningococcal disease in selected counties -
United States, 1989-1991. Morbidity and Mortality Weekly Report
1993; 42(25): 498.
- Centers for Disease Control and
Prevention. Control and prevention of meningococcal disease and
Control and prevention of serogroup C meningococcal disease: evaluation
and management of suspected outbreaks: recommendations of the
Advisory Committee on Investigation Practices (ACIP). Morbidity
and Mortality Weekly Report 1997; 46 (No. RR-5).
- Edwards, E. A., L. F. Devine, C. H. Sengbusch, H. W. Ward. 1977.
Immunological Investigations of Meningococcal Disease. III. Brevity
of group C acquisition prior to disease occurrence. Scand J Infect
Dis 9:105-110.
- Last, J. M. (ed.). Public Health and Prevention Medicine (13th
ed.) New York: Appleton-Century-Crofts, 1992. 8. Mandell, G.L.,
Bennett, J.E. and Dolin, R. Principles and Practice of Infectious
Diseases, 4th ed. New York: Churchill Livingston Inc., 1995.
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