Bacterial meningitis claims 170,000 lives worldwide every year, according to the World Health Organisation (WHO). It remains a serious threat to global health and one of the most feared infectious diseases of children worldwide. Meningitis epidemics and outbreaks can have devastating impacts on entire populations.
Bacterial meningitis occurs when bacteria enters the bloodstream and migrates to the brain and spinal cord. But can also occur when the bacteria directly invades the meninges as a result of an ear or sinus infection. Bacterial meningitis is most common in children under 5 years old, especially babies under the age of 1. It is also known to affect teenagers and young adults.
Symptoms of meningitis are non-specific and are very similar to those seen with flu:
Meningitis can often be misdiagnosed for some other condition. This can be deviously misleading as an individual’s health can quickly deteriorate to a state between life and death within a matter of hours.
There are three types that are responsible for causing most of cases of bacterial meningitis:
- Haemophilus influenzae.
- Streptococcus pneumonia.
- Neisseria meningitidis.
Before the HiB vaccine became available, Haemophilus influenzae was the leading cause of bacterial meningitis in children. Rough estimates put the number of people infected at 2.2 million with about 520,000 deaths.
Even with a pneumococcal vaccine available, Streptococcus pneumonia still remains as one of the most common causes of bacterial meningitis in infants, young children and adults. It is a common cause of pneumonia, ear and sinus infections.
Neisseria meningitidis is another leading cause of bacterial meningitis. This infection is highly contagious, and mainly affects teenagers and young adults. It is also most associated with meningitis epidemics and outbreaks.
There are 12 types of Neisseria meningitidis, of which 6 (A, B, C, W135, X and Y) are most commonly identified in meningitis epidemics. Neisseria meningitidis spreads from person to person through droplets when an infected person coughs or sneezes. Living in close proximity with an infected person, kissing and sharing utensils can facilitate the spread of the disease as well. The bacterium can be harboured in our throats without any signs or symptoms. The WHO estimates that 10% of the population carries Neisseria meningitidis in their throats at any given time. At any juncture, the bacteria can overwhelm an individual’s immune system and spread throughout the bloodstream to the brain and other vital organs.
Illnesses caused by Neisseria meningitidis is collectively known as meningococcal disease:
- Meningococcal meningitis
- Meningococcal septicaemia
Meningococcal meningitis can cause severe brain damage and is fatal in 50% of cases if untreated, according to WHO. It occurs when the protective membranes covering the brain and spinal cord (meninges) becomes infected and swells.
Symptoms typically develop within 3-7 days after exposure and include:
- Rapid onset of fever
- Stiff neck
- Sensitivity to light (photophobia)
Meningococcal meningitis can cause death in a matter of hours. When death does not occur, it is estimated by the CDC that 15% of survivors will have permanent disabilities such as brain and nerve damage, and hearing and vision loss. All this is can happen even with immediate and effective medical treatment.
Meningococcal septicaemia is a more severe but less common form of meningococcal disease. It occurs when Neisseria meningitidis infects the bloodstream and begins to multiply uncontrollably in the bloodstream.
Symptoms of meningococcal septicaemia include:
- Cold hands and feet
- Cold chills
- Severe aches or pain in the muscles, joints, chest or abdomen (belly)
- Rapid breathing
- A dark purple rash
Children and adults can die very quickly from meningococcal septicaemia as it spreads very quickly, damaging the walls of blood vessels and causing bleeding in the skin and organs which leads to rapid organ failure. In non-fatal cases, permanent disabilities can include amputation of toes, fingers, or limbs, and severe scarring as a result of skin grafts.
Death and permanent disabilities from both meningococcal meningitis and septicaemia can occur even with prompt and immediate medical treatment. Antibiotics are available to treat bacterial meningitis but the window for treatment is extremely fleeting due to the rapid onset of complications.
Everyone is at risk of meningitis infection but there certain types of individuals that are at greater risk of infection:
- Children who attend day care and preschool.
- Adults in constant contact with children such as teachers, daycare workers, etc.
- University students, military personnel and individuals living in close quarters.
- Individuals with weakened immune systems.
- Travellers to Mecca during Hajj and Umrah.