Invasive Meningococcal Disease

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What is invasive meningococcal disease?

Neisseria meningitidis is a bacterium (germ) that can cause meningococcal meningitis (inflammation of the membranes covering the brain) and meningococcemia (a serious form of blood poisoning).

These two conditions are known as invasive meningococcal disease.

Up to 10% of people carry the bacterium that can cause invasive meningococcal disease in their nose or throat at any given time. When people carry the bacterium but do not have any symptoms, they are referred to as carriers.

What are the symptoms of invasive meningococcal disease?

Invasive meningococcal disease is a very serious illness that can develop quickly.

If you or your child develops any of the symptoms described below, seek medical attention immediately:

  • Sudden onset of fever, headache, stiff neck, nausea, vomiting, sensitivity to bright lights or drowsiness, confusion or coma, as these could be early symptoms of meningococcal meningitis
  • Sudden onset of fever, chills, malaise, muscle pain and a rash of tiny, reddish-purple spots or bruises that may occur anywhere on the body, as these could be early symptoms of meningococcemia
  • In an infant, sudden onset of fever, irritability, difficulty in waking up, difficulty feeding, vomiting, stiff neck and bulging fontanelle (the soft spot on a baby’s head), as these could be early symptoms of invasive meningococcal disease
How does invasive meningococcal disease spread? 

The bacteria that cause invasive meningococcal disease are spread by direct contact with secretions from the nose and throat (saliva and mucus) of an infected person and carrier.

Invasive meningococcal disease bacteria are also spread through saliva while kissing on the mouth or sharing items such as cigarettes, toothbrushes, eating utensils and drinking bottles.

The contagious period for invasive meningococcal disease is 7 days before the onset of symptoms and up to 24 hours after the start of antibiotic treatment.

The contagious period for a carrier is until the bacteria are no longer present in the secretions from the nose and throat.

What is the treatment for invasive meningococcal disease?

All confirmed invasive meningococcal disease cases are treated with antibiotics.

Early medical treatment is critical to reduce the risk of complications and death.

Who is at greatest risk of developing invasive meningococcal disease?

People who are at highest risk of developing invasive meningococcal disease include:

  • Very young children, adolescents and young adults
  • People who have weakened immune systems, such as those with HIV infection
  • People with chronic diseases, such as sickle cell disease
  • People who have been in close contact with a person who has invasive meningococcal disease, such as those living in the same house or those who had direct contact with their secretions through sharing of items

Casual contacts such as school, work or transportation contacts, and persons who did not have direct contact with the secretions from the nose and throat of a person who has invasive meningococcal disease, are not considered to be at high risk of developing invasive meningococcal disease.

How can invasive meningococcal disease be prevented?

To prevent the spread of bacteria, it is recommended that you wash your hands well, especially after coughing and sneezing, before preparing food and before eating.

In general, avoid sharing items such as: cigarettes, toothbrushes, eating utensils and drinking bottles. 

Another way to protect yourself against certain strains of bacteria that cause meningitis is to be immunized with the appropriate vaccines.  

At 12 months, children are immunized against meningococcal C , which is included in the routine immunization schedule.

Additionally, there is a vaccine which protect people from meningitis caused by serotypes A, C, Y and W-135. It is offered to grade 7 students in the province of Ontario.

Depending on the age of the child, a meningococcal vaccine is required for school or daycare attendance.

What is Ottawa Public Health's role?

All suspect or confirmed cases of invasive meningococcal disease must be reported to public health for follow up.

When the Communicable Disease Control Program receives a case report, they identify and notify close contacts, and assess the need for preventive treatment with antibiotics.

Close contacts may also be given a meningococcal vaccine.

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