Meningitis is defined as inflammation of the meninges (the membranes covering the brain and spinal cord). Meningococcal meningitis is a specific type of meningitis caused by the bacterium Neisseria meningitidis. This disease is contagious and can cause inflammation of the brain lining and spinal cord, leading to swelling. To date, six serogroups of meningococcal bacteria—A, B, C, W, X, and Y—are known to be associated with outbreaks.
Meningococcal meningitis has spread worldwide, with the highest incidence found in sub-Saharan Africa, an area known as the "Meningitis Belt." This region stretches from Senegal in the west to Ethiopia in the east and includes 26 countries. In this belt, large epidemics occur every 5 to 12 years, with incidence rates reaching up to 1,000 cases per 100,000 people. In other regions, the incidence is lower, and outbreaks are sporadic.
In 2023, a total of 6,469 cases were reported, including 570 confirmed cases and 420 deaths. These cases were distributed across 5 countries in the WHO Western Pacific Region (Taiwan, Singapore, New Zealand, Australia, and China), 3 countries in the WHO Africa Region (DR Congo, Niger, and Nigeria), 2 countries in the WHO European Region (Italy and Norway), and 1 country in the WHO Region of the Americas (United States).
Additionally, cases of meningococcal meningitis have often been reported in Saudi Arabia. Between 2002 and 2011, there were 184 confirmed cases (only 9% involving Hajj and Umrah pilgrims), mostly caused by serogroup W135. However, between 2012 and 2019, 44 confirmed cases were reported, all involving Saudi nationals.
Symptoms
Symptoms may initially resemble those of the flu but can worsen rapidly. The most common symptoms include fever, headache, and neck stiffness. Other symptoms may include nausea, vomiting, photophobia (increased sensitivity to light), and neurological disturbances such as lethargy, delirium, coma, and in some cases, seizures.
Physical examination may reveal meningeal signs (neck stiffness, Kernig's or Brudzinski's sign), neurological signs such as decreased consciousness, purpura (either localized on the limbs or spread across the body, skin, or mucous membranes like the conjunctiva), low blood pressure accompanied by shock symptoms, and focal infections such as arthritis, pleuritis or pneumonia, pericarditis, and episcleritis.
Causes
Several risk factors can contribute to meningococcal meningitis, including close contact with infected individuals, overcrowded living conditions, exposure to cigarette smoke (active or passive), low socioeconomic status, climate changes, and a history of upper respiratory tract infections.
Mass travel (e.g., to affected countries) plays a significant role in disease transmission. A notable outbreak occurred in Mecca in 1987 during the Hajj pilgrimage, where pilgrims were more affected than the local population. Such epidemics may be triggered by the introduction of virulent strains like serogroup A, which can be fatal. However, carriers of meningococcal bacteria cannot be used to predict future outbreaks.
Prevention
Antibiotics are a key treatment for patients with meningococcal meningitis. However, because this disease can be life-threatening, it should be considered a medical emergency, and patients must be referred to a hospital. If the infection is severe, treatment may include respiratory support, medications for low blood pressure, removal of necrotic tissue, and wound care.
Prevention methods for meningococcal disease include vaccination, chemoprophylaxis, and risk communication. Vaccination is the most effective method of prevention. Additional preventive measures include maintaining a healthy lifestyle, getting adequate rest, and avoiding close contact with infected individuals.
