Anyone arriving in Saudi Arabia from a country infected with yellow fever requires a vaccination certificate for entry. Not compulsory, but definitely advisable, is vaccination against meningococcus, hepatitis A and typhoid fever. There is a malaria risk in the south and parts of the western region of the country and visitors should take advice on anti-malarial precautions at least four weeks before leaving; an outbreak of cerebral malaria has occurred in Jizan. Food poisoning is a risk outside the good hotels. Visitors should only drink bottled water. The standard of medical care and facilities in Saudi Arabia is high, but treatment is expensive, therefore health insurance is strongly advised for all travellers.