As mosquitoes mostly spread dengue virus while feeding on iron deficit blood, researchers suggest consuming iron-rich food if dealing with iron deficiency, anaemia or dengue fever. Dengue is most commonly acquired in urban environments, and the expansion of cities in the tropics has been accompanied by an expansion in dengue infections. The reason has to do with the mosquitoes' own immune systems. Cells in a mosquito's gut take up iron in the blood and use it to produce reactive oxygen. Reactive oxygen kills the dengue virus. In any case, Wang said, understanding how dengue is transmitted will help public health authorities and scientists develop new ways to control the disease, and hopefully similar viruses such as Zika and West Nile virus as well.