Meningococcal infection is a bacterial infection caused by the bacterium Neisseria meningitidis, also called meningococcus. Four sero groups (namely A, B, C and W135) of Meningococcus are known to cause epidemics in many parts of the world. The largest epidemics have occurred mainly in the semi-arid areas of sub-Saharan Africa, known as the “African meningitis belt”. This disease occurs mostly in winter months and is mainly found in infants, older children and young adults but can occur at any age. This infection results in meningitis and septicemia commonly.
In this disease the meninges (protective membranes, which cover the brain and spinal cord) become infected and swell. The visible symptoms include sudden onset of fever, headache and stiff neck. Infants may not have these obvious symptoms, but may appear inactive, irritable, not feeding, vomiting and can have bulging fontanelle (soft spot in the skull). Additionally, persons may have nausea, vomiting, photophobia (increased sensitivity to light), altered mental status (confusion) and coma. The symptoms develop within 3-7 days post exposure to bacteria.
It is a very serious disease which can be fatal within a few hours as well. Permanent disabilities including hearing loss or deafness and brain damage can also occur in the patients survived.
Meningococcal Septicemia (Meningococcemia)
Meningococcus when invade the bloodstream can cause septicemia or Meningococcemia. This disease is even more serious and deadly as the bacteria have access to the whole body through the bloodstream. It damages the walls of the blood vessels and causes bleeding from the skin and other organs. Symptoms of the disease are fatigue, vomiting, cold hands and feet, chills, severe body aches, muscle aches or Myalgia of chest, abdomen, joint pain or arthritis, rapid breathing, diarrhea and a characteristic dark purple hemorrhagic rash. Death can occur in just a few hours in fatal cases. Permanent disabilities in the survivors can occur due to unavoidable amputation of toes, fingers, or limbs or scarring of skin due to life saving graft surgeries.
How are Meningococcal diseases transmitted?
Meningococcus resides in the upper respiratory tract of humans. They can be transmitted through direct contact with oral secretions like the spit and saliva of infected persons or carriers living together. Meningococcus is not as contagious as influenza or Hib as this bacteria are short lived outside the human host and has no extra reservoir. It cannot be spread by casual contact or breathing the infected air.
How can Meningococcal diseases be prevented?
Prevention of this disease can be done best by vaccines, also by not coming in close contact with the diseased person and by chemical prophylaxis (giving antibiotics in advance to people living in the close contact with the diseased person). However, antibiotic resistant isolates of meningococcus have been discovered in various outbreaks in the world, including Indian states as reported by the National Institute of Communicable Diseases (NICD). Meningococcal vaccines are not 100% effective, so there is always a slight chance of getting sick with this disease. Awareness of symptoms is important in seeking early medical help which is essential to control deaths by this deadly disease. Natural immunity gained by this disease does not provide lifelong protection against this disease.
Who should receive the Meningococcal vaccines?
Routine vaccination is not recommended except during epidemic situations. Meningococcal vaccines are especially advised for the following persons:
- High risk group children or persons with certain diseases like complement component deficiency and asplenia (no spleen and nonfunctional spleen)
- Persons under medications and undergoing surgical procedures that weaken the immune system are also under high risk of getting meningococcal diseases
- Persons living in confined spaces (e.g. Children living in orphanages, jail inmates, soldiers in barracks, etc.) are at increased risk of meningococcal outbreak
- International travellers to Hajj (Saudi Arabia) and sub- Saharan Africa
- Persons travelling to or residing in the state where a Meningococcal outbreak is recent