Malaria in Zanzibar

Zanzibar, a" semi-autonomous region composed of two islands off the coast of Tanzania in East Africa," has "drastically reduced malaria" in the past decade. "Zanzibar's aggressive campaign against malaria has reduced infections from as much as 40 percent of its 1.2 million people to less than 1 percent." Recent concerns regarding the reintroduction of malaria to the region sparked a study that tracks the travel patterns of Zanzibar residents by their telephone reception.

"University of Florida researchers at work on a malaria elimination study in Africa have become the first to predict the spread of the disease using cell phone records." Without accessing personal information, "scientists analyzed more than 21 million calls to determine how often residents of Zanzibar travel and where they go." The researchers discovered that "short trips to Dar es Salaam on the Tanzanian mainland nearby, where malaria is relatively uncommon", dominated the travel patterns. "However, they also revealed that a few" Zanzibaris "travel back and forth from more distant areas of Tanzania where the risk of getting the disease is much higher -- posing the greatest threat to elimination."

"Most callers never left Zanzibar, which means they posed no threat of reintroducing the Malaria parasite...About 12 percent did leave the islands, but most of those only visited relatively safe Dar es Salaam, and usually for just one or two days at a time. However, a few hundred residents made trips to regions of western and southern parts of Tanzania, where as many as 40 percent of the residents have the malaria parasite."

Zanzibar has made huge advances against malaria in the past decade; however, those advancements may be reversed by reintroduction. Tanzania, including distant areas that are infected with malaria, must reduce malaria transmission in order to keep infections in Zanzibar low. With concerted effort across Tanzania, the country may eliminate malaria from within its borders.

Sources:
University of Florida. "Cell Phone Records Used to Predict Spread of Malaria." ScienceDaily 17 December 2009. 17 December 2009 .