Cerebrospinal meningitis is the epidemic disease caused by meningococcus , spherical bacteria that normally inhabit the nasopharynx of healthy human carriers. Sometimes, however, they infect the blood and cerebrospinal fluid, causing a potentially fatal inflammation of the meninges, or membranes, covering the brain and spinal cord. Meningococcal vaccine is recommended for travelers going to the 'meningitis belt' of Africa, Egypt, parts of India and parts of Brazil. Yellow fever , caused by a virus transmitted by the bite of an infected mosquito, may occur in a mild form like a flu but in severe cases is characterized by sudden fever, headache, backache, nausea, and vomiting. There is no specific treatment.
Most victims recover spontaneously and thereafter have life-long immunity.
Five to ten percent of victims die within 8 days of the onset of symptoms. Vaccination confers protection for at least 10 years. A certificate of vaccination is required by some countries if you have traveled in endemic zones in Africa or tropical America.