Most common cause of meningococcal epidemic?

Ans. is 'a' i.e., A Meningococcal meningitis (cerebrospinal fever) It is an acute communicable disease caused by N. meningitidis. Out of 13 serogroups, group A, B and C are most impoant. Group A is associated with epidemics and group C mostly with localized outbreaks, while group B causes both epidemics and outbreaks. Group 29-E, W-135 and Y also frequently cause meningitis. Reservoir - Human nasopharynx is the only reservoir Source of infection - carriers are the most impoant source of infection, not the clinical cases. Age group - Children between 3 months to 5 years. Outbreaks of meningococcal meningitis occur more frequently in the dry and cold months of the year. Period of communicability - until meningococci are no longer present in discharges from nose and throat. Cases rapidly lose their infectiousness within 24 hours of specific treatment. Meningococcal meningitis is a very fatal disease. In untreated cases moality is 80%. The disease is fatal in 5-10% of cases even with prompt antimicrobial treatment in good health care facility.