The next highest incidence is recorded for teenagers between 15 and 19 years of age. In some poorer countries, such as in West and Central Africa and Iran, there are occasional epidemics. Someone with the infection will become very ill, though not all the symptoms will occur at once. A characteristic rash develops and may start as a cluster of pinprick blood spots under the skin, spreading to form bruises under the skin. The rash can appear anywhere on the body.
Symptoms can develop within hours.
Meningococcal infection is not highly infectious. The bacteria are passed by close contact, so family members of a case and others who have close contacts with a case may be spreading the same germs. This usually means household or kissing contacts. Close contact in residential accommodation, such as student halls of residence, and schools can also give the opportunity for the spread of infection. As the bacteria cannot survive for long outside the human body, infection cannot be caught from water supplies, swimming pools, or buildings.