Globalization and disease
Globalization, the flow of information, goods, capital, and people across political and geographic boundaries, allows infectious diseases to rapidly spread around the world, while also allowing the alleviation of factors such as hunger and poverty, which are key determinants of global health. The spread of diseases across wide geographic scales has increased through history. Early diseases that spread from Asia to Europe were bubonic plague, influenza of various types, and similar infectious diseases.
Contemporary engraving of Naples during the Naples Plague in 1656
An early medical illustration of people with syphilis, Vienna, 1498
In epidemiology, a disease vector is any living agent that carries and transmits an infectious pathogen such as a parasite or microbe, to another living organism. Agents regarded as vectors are mostly blood-sucking insects such as mosquitoes. The first major discovery of a disease vector came from Ronald Ross in 1897, who discovered the malaria pathogen when he dissected the stomach tissue of a mosquito.
A mosquito shortly after obtaining blood from a human (note the droplet of blood plasma being expelled as the mosquito squeezes out excess water). Mosquitos are a vector for several diseases, including malaria.
The deer tick, a vector for Lyme disease pathogens
This figure shows how the Flavivirus is carried by mosquitos in the West Nile virus and Dengue fever. The mosquito would be considered a disease vector.
Public health agencies educate people about many different disease vectors. This artwork, at the London School of Hygiene and Tropical Medicine, shows 10 different animal vectors.
