Southwest of Cairo, the Nile branches into a network of canals that feed Fayum, a fertile agricultural basin that was a center of civilization and royal pyramid-building for several centuries. The unusual geology responsible for Fayum’s rich terrain may have also led to the prevalence of malaria and tuberculosis in the region during these ancient times.
Ancient DNA (aDNA) from sixteen mummified heads recovered from the region reveals that at least four of these individuals suffered both these infections simultaneously. Many of the others showed signs of infection with either malaria or tuberculosis, as scientists report in a recent PLOS ONE study.
DNA extracted from muscle tissue samples was tested for the presence of two genes specific to Plasmodium falciparum, the malarial parasite, and another gene specific to Mycobacteria, which cause tuberculosis. Two samples tested positive for DNA specific to Plasmodium, one tested positive for the mycobacterial gene, and four individuals tested positive for DNA from both infectious agents, suggesting they suffered both infections together while alive. A previous study suggests that both malaria and tuberculosis were rampant in the Fayum region in the early 19th century, but the age of these mummified samples extends evidence of these diseases in Lower Egypt as far back as approximately 800 B.C.
The World Health Organization estimates that malaria is almost non-existent in the Fayum basin and the rest of Egypt now, but before its eradication, high levels of infection were seen in certain parts of the country, and were strongly linked to certain geological features. The lakes and canals that made the Fayum region so fertile also served as breeding grounds for the mosquito that carries the malarial parasite.
The heads tested here (all were missing bodies) were recovered from a village cemetery on the west bank of the lower Nile, and date from about 1064 BC to 300 AD, a period marked by an agricultural boom and dense crowding in the region, especially under the rule of the Ptolemies. These conditions may have increased the chances of tuberculosis incidence and spread of the disease. As the aDNA from these mummified heads attests, these living conditions and the unique irrigation of the Fayum basin likely created a harbor for both malaria and tuberculosis in ancient populations of this region.
Citation: Lalremruata A, Ball M, Bianucci R, Welte B, Nerlich AG, et al. (2013) Molecular Identification of Falciparum Malaria and Human Tuberculosis Co-Infections in Mummies from the Fayum Depression (Lower Egypt). PLoS ONE 8(4): e60307. doi:10.1371/journal.pone.0060307
Image: Sailing on the Nile by David Corcoran