<prompt> What is the mass chemoprophylaxis for meningococcal meningitis ?RifampicinChloramphenicolTetracyclinePenicillin  <response>: Recommended Chemoprophylaxis for High-Risk Close Contacts: Age Dose Duration Cautions RIFAMPICIN: 1 month 5 mgkg Oral every 12 hrs 2 days 1 month 10 mgkg Oral every 12 hrs 2 day Not recommended for use in pregnancy CEFTRIAXONE: 15 years 125mg IM single dose 15 years 250 mg IM single dose CIPROFLOXACIN 18 years 500 mg Oral single dose Not recommended for use in pregnancy ref : park 21st ed 