The Final VPMD: N. Meningitidis ACWYB (Meningococcal disease)
What is N. meningitidis?
Neisseria meningitidis (N. meningitidis) is a bacterium known to cause two significant infectious diseases, one that infects the CNS (meningitis± encephalitis) and the other the bloodstream (meningococcemia). The strains most commonly associated with significant disease worldwide are A,C,Y,W-135 and B; within the US, strains B,C and Y cause the most disease. These infections can affect anyone, but as with most infectious diseases, the very young, old and immunocompromised (i.e. asplenia, HIV, complement inhibition) carry the greatest risk for disease severity and complications. N. meningitidis is spread from person to person through respiratory droplets from those with or without symptoms. Complications that can occur from an N. meningitidis infection include septic shock, hearing loss, seizures, abnormal blood clotting (DIC), myocarditis, organ failure and death. Infection with N. meningitidis can be very devastating and lead to irreparable damage, which, in addition to the evolution of drug resistant strains, accounts for the importance of preventative measures including vaccination and post exposure prophylaxis.
What symptoms do you have when infected with N. meningitidis?
Meningitis/encephalitis: Usually presents with fever, headache and neck stiffness, +/- altered mental status in older children and adults. In infants and younger children, symptoms are usually decreased activity, poor feeding, irritability, vomiting, bulging fontanelle & fever.
Meningococemia: Fever, chills, brusing/rash, severe muscle pain, decreased energy, cold extremities.
How is an N. meningitidis infection diagnosed?
Clinical symptoms (as described above) along with isolation of the bacteria from blood samples (blood culture/PCR) and or CSF (lumbar puncture) lead to diagnosis.
What is the treatment for N. meningitidis infection?
When it has been determined that N. meningitidis is the cause of the CNS or bloodstream infection, antimicrobials effective towards this organism are used in addition to medications that target symptoms. Management of these infections usually require care within the intensive care units of the hospital allowing for close observation.
How are N. meningitidis infections prevented?
Vaccination plays a central role in mitigating the risk of disease spread and severity. In the early 2000’s the meningococcal vaccine covering strains ACWY is recommended for those 2 months and older whom are at increased risk for severe disease (i.e. asplenia, immunocompromised, HIV, travel to hyperendemic countries) and to all those whom are 11 years and older. As of today, Men B vaccine is recommended for those who are 10 years and older with medical conditions that place them at increased risk for severe disease (immunocompromised, asplenia, HIV etc) and those 16 and older who will live in close quarters where spread and epidemics are greatest ( i.e. military or college dormitory housing).
For those whom are in close prolonged contact with someone diagnosed with a meningococcal disease, prophylactic antibotic therapy is recommended to mitigate the development of severe infection.
Sources: CDC, WHO, Cleveland Clinic, AAP, UpToDate