It should be taken daily, starting one day before entering the area, daily while in the area and daily for four weeks after leaving the area. Mefloquine should be taken every seven days, starting a week before entering the area, weekly while in the area and weekly for four weeks after leaving the area. Doxycycline should be taken once daily, starting two days before entering the area, daily while in the area and daily for four weeks after leaving the area. Start your prophylaxis course preferably a week before entering the area. Continue the course for a minimum period of four weeks after leaving the area.
Symptoms can appear up to six months after leaving a malaria area.
With the correct precautions, conscientiously applied, visits to even high-risk tropical areas are statistically safe. Most tourist areas in Southern Africa, if visited at the right time of year, are relatively low-risk, but it is always sensible to take precautions.