When you go on African safaris you should talk to your physician for advice with regards to malaria protection and necessary vaccinations. Pregnant women can go on safari even without vaccinations and malaria protection as long as they visit non yellow fever and malaria free areas.
Malaria protection is always a discussion issue as there is no guaranteed protection and the tablets available can have unpleasant side effects. Choosing the right travel time and using repellents can be just as good. It is a personal question and it is your personal decision what to do.
In most of the lodges and camps the water from the tap is no drinking water. You will be advised by he lodge. Use the bottled water provided by the lodges to avoid stomach problems that can spoil your safari. If you want to be absolutely sure you do not get in touch with the water, do eat only cooked vegetable.
Some guests take a sip of whisky in the morning for the stomach, but I’m not sure, if this is the only reason for having a drink.
However, being on safari is great and you should thoroughly enjoy it. The food is usually very good and plenty.