The meningococcus is a bacterium (bacteria germ), Neisseria meningitidis, that can be found at the back of the throat or in the nose in about 10% of the community at any given time.
Although most people who ‘carry’ this germ in their throat or nose remain well, they are able to spread it to others, a few of whom may subsequently become very ill. It is spread in the fine droplets that are shed through e.g. coughing and sneezing.
What is meningococcal disease
Meningococcal disease is an uncommon but severe infection that occurs when the meningococcal germ ‘invades’ the body from the throat or nose. This is thought to happen soon after the germ has been acquired from a carrier.
It occurs in 2 main forms:
- meningococcal septicaemia, when the germ invades the bloodstream and causes blood poisoning
- meningococcal meningitis, when the germ infects the outer lining around the brain and spinal cord.
Sometimes septicaemia and meningitis can occur at the same time.
Meningococcal septicaemia can be very serious and cause death after even a very short illness. The patient usually is obviously sick, has a fever and may have marked joint or muscle pains; and there is often a rash. The rash may start anywhere on the body as tiny red or purple spots but they soon spread and enlarge to look like fresh bruises. The rash does not fade when pressure is applied to it, e.g. with the thumb or a clear glass.
The rash must be taken seriously as the person requires urgent medical attention.
The typical symptoms of meningococcal meningitis include fever, a stiff neck, severe headache, dislike of bright lights, vomiting, joint or muscle pains, drowsiness and even coma; there may also be a rash with the same features as those described above.
Typical symptoms include all of the following:
- a stiff neck
- severe headache
- dislike of bright lights
- joint or muscle pains
- drowsiness and even coma
- there may also be a rash.
Symptoms in young babies may be different and include:
- refusing feeds
- a high-pitched moaning cry
- irritability and dislike of being handled
- blank staring expression
- lethargy or drowsiness
- pale blotchy complexion.
There are 6 different groups of the meningococcal bacteria that cause nearly all disease globally (A, B, C, W-135, X and Y). The most common in Australia and the Northern Territory is group B.
Group C disease is now rarely seen because children are vaccinated against group C at the age of 12 months.
Since 2003 cases of meningococcal disease have been declining nationally with only 2-4 cases diagnosed per year in the Northern Territory over the last 3 years. The overall fatality rate of meningococcal disease is 10%.
How easy is it to catch meningococcal disease
Although the germ is spread in droplets that are shed from the nose or throat it is fortunately not easy to catch the disease. This is because the meningococcal germ does not survive for long outside the body. Close and prolonged contact with a carrier is usually required for the germ to spread to other people.
Evidence suggests that contact with saliva outside of the body is not important in the transmission of meningococcal disease. Therefore sharing of drink bottles does not pose a risk for meningococcal transmission.
Young children under 5 years of age, and young adults (15 to 24 years of age) are at highest risk of acquiring meningococcal disease and there is usually a seasonal increase in the winter to early spring months.
Even though it is hard to catch and uncommon, meningococcal disease is a feared disease that is often featured in the media. This is because it can be fatal even in healthy individuals and because outbreaks of meningococcal disease, although very infrequent, can occur.
Some types of meningococcal disease can be prevented by vaccination (see below).
Sometimes cases of meningococcal disease can happen in clusters when bacteria spread from a carrier to more than 1 person. Treatment of a carrier with antibiotics has been shown to stop further spread but because there is no quick and accurate test to identify carriers, all of the ‘household contacts’ of a case are recommended to have antibiotic treatment.
The purpose of the antibiotic is to eliminate the germ from the nose or throat of the carrier in an effort to prevent further spread to others.
There is a small, but real risk for those who live in the same house as a person with meningococcal disease to also develop disease. As this may occur despite taking the antibiotic, contacts must also be told to be aware for the symptoms of the disease and in some circumstances may be offered vaccination.
Contacts of cases of meningococcal disease should share the information about the disease with their close contacts to raise awareness about signs and symptoms of meningococcal disease. Early presentation of possible cases to medical care is important. Any treating doctor should be made aware if the person presenting is a possible meningococcal contact.
Sometimes other contacts are also identified by public health authorities and given the above mentioned advice and antibiotic. However it is very important that the public health authorities are involved in the identification of other contacts because the antibiotic should be used very carefully.
Cigarette smoking, both active and passive, appears to increase the risk of a person developing meningococcal disease.
There are 4 types of meningococcal vaccines available in Australia.
The meningococcal C (MenC) vaccine used in the Northern Territory is a combination MenC and Haemophilus influenza B vaccine called Menitorix® and is part of the childhood immunisation schedule (given at 12 months). There are 2 types of quadrivalent meningococcal vaccines (conjugate and polysaccharide) available which provide protection against serogroups A, C, W-135 and Y.
These may be recommended for travel to certain countries and for people with high risk medical conditions. A vaccine to cover serogroup B meningococcal disease (MenB) is now registered for use in children from 2 months of age.
The quadrivalent vaccines and the MenB vaccine are not included in the national program and therefore generally not funded but can be purchased privately with a script from your doctor.
For more information contact your nearest Centre for Disease Control.
Last updated: 27 June 2017