Meningitis outbreaks are common in an area of sub-Saharan Africa known as the meningitis belt, where approximately 300 million people are at risk in an area stretching from Senegal in the west to Ethiopia in the east. Epidemics occur during the dry season (December to June) and tend to occur in a cyclical manner across the belt.
Meningococcal meningitis is an infection of the meninges, the membrane surrounding the brain and spinal cord, caused by the bacterium neisseria meningitidis. There are several strains (A, B, c, X and W135), some of them responsible for epidemics. As the bacteria is transmitted through droplets in the air, high concentrations of people and cramped living conditions facilitate the spread of the disease.
Most individuals will be asymptomatic carriers of the bacteria and remain completely well; however when the bacteria crosses the mucosal barrier, a person will show signs of the disease, which usually manifests with fever, headache and neck stiffness as well as rash, convulsions and loss of consciousness.
Without treatment for meningitis, 80 percent of patients can die, yet with early diagnosis and treatment the death rate can be reduced to 5-10 percent. As many as one in five survivors will suffer from neurological effects or hearing loss.
An epidemic is declared when 15 cases per 100,000 people per week have been detected in a region (10 cases per 100,000 people in special circumstances). once an epidemic has been identified, health workers rely on clinical diagnosis and rapid, simple treatment at a facility close to the patient. the treatment consists of a single intramuscular injection of the antibiotic oily chloramphenicol or ceftriaxone. in most cases a single dose leads to full recovery - a second dose is given if there is no improvement after 24 hours. An alternative treatment of a daily injection of ceftriaxone for five days is used for children aged two months to two years old, due to the possibility of other bacteria causing the meningitis.
In the 2006 epidemic season, after several years of low incidence, there was a marked rise in meningitis outbreaks across the meningitis belt. This increase could signal the beginning of a new epidemic wave in the coming years. In 2006/2007, the overall number of cases reported was more than 50,000, a significant increase over the previous year, when 35,000 cases were recorded.
During the 2006/2007 epidemic season, MSF was active in 14 outbreak responses in five countries that experienced meningitis epidemics - Burkina Faso, Chad, Sudan, Uganda and the Democratic Republic of Congo (DRC). MSF activities included the initial evaluation of the epidemics, identifying the type of meningitis and supporting case management to ensure rapid treatment for those affected by the disease. MSF also participated in mass vaccination campaigns to prevent the deadly disease from spreading.
In total, MSF was involved in the vaccination of 2.5 million people against meningitis and treated 10,500 patients affected by the disease.