In the major cities the water is treated, and you can drink the water after filtering it through a filter. In other places, or if you are on safari, it is recommended to bring bottled water, boil it, or use hydroclonazone tablets.
Malaria is a problem in many parts of the country, but not in Nairobi. So, if you are staying in the city, you don’t need to use any medication. If you are going out of Nairobi for a longer period it is advised to use some sort of preventive medication. But there is malaria resistance in many parts, so the best prevention is to wear long-sleeved clothes, use mosquito repellent, and sleep under a mosquito net.
It is required to have a certificate of vaccination against yellow fever, and it is recommended that you be immunised against cholera, typhoid, and hepatitis A.
More information about vaccinations and tropical diseases should be achieved from your country of origin.
The private hospitals are generally well equipped, and are staffed by personnel of international standards. Government hospitals in all areas suffer from chronic shortages. See our Map of Nairobi Hospitals.